Dissertations / Theses: 'Shoulder muscle'

1

Marsden, Stuart Peter. "Muscle Wrapping Techniques Applied to the Shoulder." Thesis, University of Newcastle upon Tyne, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.512159.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Nelson, Julia Kathryn. "Shoulder Muscle Electromyography During Diagonal and Straight Plane Patterns of Movement." Thesis, University of North Texas, 1988. https://digital.library.unt.edu/ark:/67531/metadc500786/.

Full text

Abstract:

The purpose of this study was to further investigate the relationship between patterns of shoulder movement and muscular response. Thirteen females were tested against maximal manual resistance in twelve different patterns, eight straight plane, and four diagonal. Five of the six subjects who met established kinematic criteria were used for electromyographic (EMG) analysis of the anterior deltoid (AD), the middle deltoid, the posteroir deltoid (PD), and the pectoralis major. No significant differences were found between number of muscles solicited or duration of muscular effort during the different movements. Maximal EMG was significantly higher for the AD in abduction and in flexion than in the other patterns, and for the PD in diagonal flexion with abduction and in transverse abduction.

APA, Harvard, Vancouver, ISO, and other styles

3

Dashottar, Amitabh. "Posterior Shoulder Tightness Measurements: Differentiating Capsule, Muscle and Bone." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1337880690.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Thigpen, Charles A. Padua Darin A. "Effects of forward head and rounded shoulder posture on scapular kinematics, muscle activity, and shoulder coordination." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,261.

Full text

Abstract:

Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2006.
Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Interdisciplinary Human Movement Science (School of Medicine)." Discipline: Human Movement Science; Department/School: Medicine.

APA, Harvard, Vancouver, ISO, and other styles

5

Redhead, Lucy. "The role of selected muscle activity in idiopathic shoulder instability." Thesis, University of Brighton, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411706.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Kelson, Denean M. "Muscle Activation Patterns and Chronic Neck-Shoulder Pain in Computer Work." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83759.

Full text

Abstract:

Prolonged computer work is associated with high rates of neck and shoulder pain symptoms, and as computers have become increasingly more common, it is becoming critical that we develop sustainable interventions targeting this issue. Static muscle contractions for prolonged periods often occur in the neck/shoulder during computer work and may underlie muscle pain development in spite of rather low relative muscle load levels. Causal mechanisms may include a stereotypical recruitment of low threshold motor units (activating type I muscle fibers), characterized by a lack of temporal as well as spatial variation in motor unit recruitment. Based on this theory, although studies have postulated that individuals with chronic neck-shoulder pain will show less variation in muscle activity compared to healthy individuals when engaged in repetitive/monotonous work, this has seldom been verified in empirical studies of actual computer work. Studies have rarely addressed temporal patterns in muscle activation, even though there is a consensus that temporal activation patterns are important for understanding fatigue and maybe even risks of subsequent musculoskeletal disorders. This study applied exposure variation analysis (EVA) to study differences in temporal patterns of trapezius muscle activity as individuals with and without pain performed computer work. The aims of this study were to: Assess the reliability of EVA to measure variation in trapezius muscle activity in healthy individuals during the performance of computer work; Determine the extent to which healthy subjects differ from those with chronic pain in trapezius muscle activity patterns during computer work, measured using EVA. Thirteen touch-typing, right-handed participants were recruited in this study (8 healthy; 5 chronic pain). The participants were asked to complete three 10-minute computer tasks (TYPE, CLICK and FORM) in two pacing conditions (self-paced, control-paced), with the healthy group completing two sessions and the pain group completing one. Activation of the upper trapezius muscle was measured using surface electromyography (EMG). EMG data were organized into 5x5 EVA matrices with five amplitude classes (0-6.67, 6.67-20, 20-46.67, 46.67-100, >100% Reference Voluntary Exertion) and five duration classes (0- 1, 1-3, 3-7, 7-15, >15 seconds). EVA marginal distributions (along both amplitude and duration classes) for each EVA class, as well as summary measures (mean and SD) of the marginal sums along each axis were computed. Finally, “resultant” mean and SD across all EVA cells were computed. The reliability in EVA indices was estimated using intra-class correlation coefficients (ICC), coefficient of variation (CV) and standard error of measurement (SEM), computed from repeated measurements of healthy individuals (aim 1), and EVA indices were compared between groups (aim 2). Reliability of EVA amplitude marginal sums ranged from moderate to high in the self-paced condition and low to moderate in the control-paced condition. The duration marginal sums were moderate in the self-paced condition and moderate to high in the control-paced condition. The summary measures (means and SDs) were moderate to high in both the self-paced and control-paced condition. Group comparisons revealed that individuals with chronic pain spent longer durations of work time in higher EVA duration categories, exhibited larger means along the amplitude, duration and in the resultant, and higher EVA SD in the amplitude and duration axes as compared to the healthy group. To our knowledge, this is the first study to report on the reliability of EVA applied specifically to computer work. Furthermore, EVA was used to assess differences in muscle activation patterns as individuals with and without chronic pain engaged in computer work. Individuals in the pain group seemed to exhibit prolonged sustained activation of the trapezius muscle to a significantly greater extent than controls, even though they did not experience pain during the performance of the computer tasks (as obtained through self-reports). Thus, these altered muscle recruitment patterns observed in the pain subjects, even in the absence of task-based pain/discomfort, are suggestive of chronic motor control changes occurring in adaptation to pain, and may have implications for the etiology of neck and upper-limb musculoskeletal disorders.
Master of Science
This study aims to assess the reliability of exposure variation analysis (EVA) to measure variation in trapezius muscle activity in healthy individuals during the performance of computer work, and to determine the extent to which healthy subjects differ from those with chronic pain in trapezius muscle activity patterns during computer work, measured using EVA. Muscle activation was recorded for eight healthy individual and five suffering from chronic neck-shoulder pain. The data were then categorized into amplitude and continuous time categories, and summary measures of resulting distributions were calculated. These measures were used to assess the reliability of participant responses to computer work of healthy individuals, as well as quantify differences between those with and without chronic pain. We found that individuals with pain activated their neck-shoulder muscles for longer continuous durations than healthy individuals, thus showing an inability to relax their muscles when performing work.

APA, Harvard, Vancouver, ISO, and other styles

7

Kolber, Morey J. "Shoulder joint and muscle characteristics in the recreational weight training population." Diss., NSUWorks, 2007. https://nsuworks.nova.edu/hpd_pt_stuetd/44.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

November, Rucia Vern-Clare. "The relationship between shoulder complex strength and throwing velocity in club cricketers." University of the Western Cape, 2016. http://hdl.handle.net/11394/5306.

Full text

Abstract:

Magister Artium (Sport, Recreation and Exercise Science) - MA(SRES)
Over the years, cricket has progressed into a game of immense physical prowess, and evolved from a traditional and conservative game into a professional sport requiring very high levels of fitness and skill. The ability to throw a ball at high velocity and with great accuracy is critical for successful performance in many ball sports, including cricket. The aim of this study focussed on examining the relationship between isokinetic strength of the shoulder complex and throwing velocity amongst club cricketers in the age group of 18-32 years. The study used a quantitative methodology with a cross-sectional research design. A convenient sample of 40 male cricketers from the University of the Western Cape was tested. Isokinetic strength of external rotators (ER), internal rotators (IR) and ratios were measured using the Biodex Pro System 4 isokinetic dynamometer at two speeds, namely, 60º•sec-¹ and 90º•sec-¹. Throwing velocity was measured using a calibrated Cordless Speed/Radar Gun. The major findings of this study were the significant correlations between IR at 60º•sec-¹ and throwing velocity for the first team (r = 0.72; p = 0.01), second team (r = 0.67; p = 0.03), third team (r = 0.73; p = 0.01) and fourth team (r = 0.69; p = 0.02). The correlation between the strength ratio at 60º•sec-¹ and throwing velocity was significant for the first team (r = 0.76; p = 0.01), second team (r = 0.83; p = 0.002), third team (r = 0.70; p = 0.02) and fourth team (r = 0.94; p = 0.0001). In conclusion, shoulder strength plays a significant role in the throwing velocity amongst club cricketers. Specifically, the shoulder internal rotators were found to be a major influence in throwing velocity. Furthermore, the shoulder strength ratio is a strong predictor of shoulder strength performance.

APA, Harvard, Vancouver, ISO, and other styles

9

McAndrew, Darryl John. "A non-invasive analysis of the structure and function of human multi-segmental muscle." School of Health Sciences - Faculty of Health & Behavioural Sciences, 2008. http://ro.uow.edu.au/theses/822.

Full text

Abstract:

The Central Nervous System (CNS) exerts extensive control over muscle activation in order to produce accurate voluntary movement, such as the complex movements of the human shoulder joint. Muscles surrounding multi-planar joints are selectively activated depending upon the movement performed, and within the radiate musculature of the shoulder, individual muscle segments exist that are capable of exhibiting specific myoelectric intensity and temporal activation patterns. The aim of this thesis was to assess the influence of inter-segment variations in contractile properties on the strategies employed by the CNS when producing voluntary movements. Experiments were designed to test the hypothesis that muscle segment neuromotor coordination (as determined by electromyographic analysis) would be sensitive to the contractile properties of individual muscle segments. A key component was the variation in isometric contraction speed ranging from slow to ballistic.Mechanomyography (MMG), which is the measure of a muscle’s physical dimensional change during contraction, is founded on the premise that the temporal aspect of muscle displacement is reflective of motor unit contractile properties and consequently the muscle fibre type composition. A series of studies were completed to establish the validity of the new Laser-MMG technique for quantifying contractile properties. The results confirmed: 1) the sensitivity of the Laser-MMG technique to modulators of physiological performance (thermal state, fatigue state, and fibre type composition variation between segments); and 2) that the contractile properties of muscle fibres varied between the individual segments of the muscles following maximal percutaneous neuromuscular stimulation (PNS). Most notably, ‘slow-twitch’ contractile properties were found in muscle segments that have a greater role in producing movement in the coronal plane, while ‘fast-twitch’ contractile properties were associated with segments having more efficient moment arms to produce movement in the sagittal plane. Furthermore, each of the muscles investigated was associated with a distinctive anatomical distribution of muscle fibre types. Muscle segment contractile properties were heterogeneous and their arrangement appears to reflect the most common or important joint movements. Moreover, the muscle segments located at the periphery of all three shoulder muscles exhibited faster contractile properties than those located in the middle of the muscle. It appears that this internal arrangement may be a consistent organisational characteristic of radiate muscles. Muscle segments within the pectoralis major, deltoid and latissimus dorsi muscles were found to be independently controlled by the CNS through manipulation of the myoelectric activation patterns, in particular: onset time; and discharge rate. The lower segments of the pectoralis major and the latissimus dorsi were identified as prime mover segments, initiating the movement and contributing the greatest myoelectric intensity. The immediately superior segments were classified as assistant movers, activating after the prime movers and contributing less to the overall movement. Furthermore, similarities in neuromotor coordination were identified between adjacent segments of individual muscles. The sequential “wave of segment activation” identified within each whole muscle appeared to ignore the anatomical boundaries between muscles, suggesting that the CNS coordinates individual muscle segments rather than the whole muscle as one unit in order to complete a motor task. This further complicates the process of controlling motor tasks as there appear to be no defined limits of muscles to which discrete functions can be applied.Coordination between prime mover segments of agonist muscles was identified, with the lower segments of pectoralis major and latissimus dorsi showing no significant difference in any of the temporal myoelectric measures. The similarity in neuromotor coordination between these segments may be the result of a common drive, suggesting that the CNS uses a simple strategy of combining the segments into one functional unit. No gross disordering of the muscle segments’ onset was identified within any of the investigated muscles, with regard to movement speed. However, the pectoralis major exhibited altered relative timing between the segments. This was particularly evident during the fast movement. The sequential “wave of activation” present during the slow movements became disordered as muscle contraction speed was increased. During fast contraction, the assistant mover segments within pectoralis major were activated later than the prime mover segments changing the relative timing of their activation. This indicates that the CNS may initially prioritise the activation of only the most essential muscle segments to commence the movement during ballistic movements, perhaps due to the imposed time constraints. This form of change in relative timing can be interpreted as a direct reflection of the differences in muscle segment fibre type composition and hence the neuromotor control of the muscle segments involved in producing the movement. Most notably, variation to the control of muscle segment excitation and contraction onset exist in the more centrally located muscle segments that exhibit slower segment contractile properties. This finding appears logical when coupled with the finding of homogeneous myoelectric peak activity. The CNS must manipulate the onset of these slower contracting segments, especially during fast movements, in order to allow enough time for all segments to achieve a uniform peak of muscle activity that occurs just prior to peak force. The variations and coordination of contractile properties, myoelectric properties and electromyographic burst patterns between adjacent muscle segments within the same skeletal muscle confirms the notion that for CNS control, individual muscle segments are considered as sub-volumes of muscle tissue that require individual neuromotor control – that they are, in effect, muscles within muscles.

APA, Harvard, Vancouver, ISO, and other styles

10

Xu, Bo Garner Brian Alan. "A linked-plane obstacle-set algorithm for modeling broad muscle paths application to the deltoid muscle /." Waco, Tex. : Baylor University, 2008. http://hdl.handle.net/2104/5212.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Stoelting, Kelli J. "The effects of hand placement on muscle activation during a closed kinetic chain exercise in physically active females /." Connect to full text in OhioLINK ETD Center, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=toledo1210791395.

Full text

Abstract:

Thesis (M.S.E.S.)--University of Toledo, 2008.
Typescript. "Submitted as partial fulfillments of the requirements for the Masters of Science Degree in Exercise Science." "A thesis entitled"--at head of title. Bibliography leaves 31-33.

APA, Harvard, Vancouver, ISO, and other styles

12

Senk, Miroslav. "Kinematical and traction experimental study of the shoulder joint dysfunction." Lyon 1, 2006. http://www.theses.fr/2006LYO10056.

Full text

Abstract:

Le but de cette thèse est d'analyser le dysfonctionnement de l'articulation de l'épaule. Les méthodes expérimentales choisies : l'analyse du mouvement et la technique de traction ont permis de comparer la condition de dysfonctionnement, représentée par l'application de l'électrostimulation du biceps brachii, et l'état physiologique, dans le cadre d'une comparaison intra-individuelle. Les résultats " préliminaires " représentent des avancements méthodologiques importants concernant (i) les mesures locales de séparation humérus/omoplate pendant la traction, (ii) une nouvelle méthode d'enregistrement de l'omoplate en utilisant un système d'analyse du mouvement et (iii) le choix de la séquence de rotation pour décrire la cinématique de l'articulation de l'épaule. Les résultats principaux démontrent les modifications significatives du rôle de stabilisation et du comportement actif du biceps brachii dans l'articulation de l'épaule dysfonctionnelle (articulation gléno-humérale)

APA, Harvard, Vancouver, ISO, and other styles

13

Ettinger, Lucas. "The Influence of Subacromial Pain on Scapular Kinematics, Muscle Recruitment and Joint Proprioception." Thesis, University of Oregon, 2013. http://hdl.handle.net/1794/13417.

Full text

Abstract:

Subacromial impingement accounts for significant burdens on the economy and individual quality of life. The development and progression of this disorder is thought to be related to overuse; however, little is known regarding biomechanical factors such as scapular kinematics, shoulder muscle recruitment and joint proprioception with respect to this disorder. The high degree of variability between individuals on these biomechanical measures limits our ability to make inferences behind the development of shoulder impingement. Here, biomechanical factors associated with impingement are investigated using within-subjects designs in order to reduce this inherent variability. Using modern clinical techniques, this dissertation is applicable towards treatment of shoulder impingement as well as scientific understanding of motor control and function in the presence of pain. This dissertation includes previously published and un-published co-authored material.

APA, Harvard, Vancouver, ISO, and other styles

14

Hager, Kristopher Ming-Ren. "Reliability of Fatigue Measures in an Overhead Work Task: A Study of Shoulder Muscle Electromyography and Perceived Discomfort." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9681.

Full text

Abstract:

This study was conducted to measure the reliability of fatigue measures in an intermittent overhead work task. Fatigue measures included several EMG based parameters and subjective discomfort ratings through use of the Borg CR-10 scale. This study was part of a larger existing study that simulates overhead work in an automobile manufacturing plant. Ten participants used a drill tool to perform an overhead tapping task for one hour at a height relative to individual anthropometry. Reliability indexes, including Intraclass Correlation Coefficients, Standard Errors of Measurement, and Coefficients of Variation were determined for each fatigue measure for each of three shoulder muscles (anterior deltoid, middle deltoid, and trapezius). High reliability implies repeatable results, and precise and credible methods. Conversely, measurement error and subject variability can lead to low reliability of measures. The results indicated that ratings of perceived discomfort (RPD) parameters (slope and final rating) showed relatively high reliability. Intercepts for mean power frequency (MnPF), median power frequency (MdPF), and root means square (RMS) also showed very high reliability. Actual slopes for MnPF, MdPF, and RMS showed low reliability overall, and normalizing slopes did not necessarily improve reliability. Taking the absolute value of slopes led to a noticeable increase in reliability. RPD slope did not correlate with any of the EMG slopes. The high reliability of RPD parameters allows for its inexpensive application to the industrial setting for similar overhead tasks. The reliability of EMG intercepts implies consistent methods; however the reliability of overall EMG trends is suspect if the slope is not reliable. Some EMG slope parameters show promise; however, more research is needed to determine if these parameters are reliable for complex tasks.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

15

Wang, Hsing-Kuo. "Shoulder injury in elite UK volleyball athletes : intrinsic factors - mobility impairment and muscle imbalance." Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324447.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Ford, Jonathan M. "Skeletal Muscle Contraction Simulation: A Comparison in Modeling." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4814.

Full text

Abstract:

Computer generated three-dimensional (3-D) models are being used at increasing rates in the fields of entertainment, education, research, and engineering. One of the aspects of interest includes the behavior and function of the musculoskeletal system. One such tool used by engineers is the finite element method (FEM) to simulate the physics behind muscle mechanics. There are several ways to represent 3-D muscle geometry, namely a bulk, a central line of action and a spline model. The purpose of this study is to exmine how these three representations affect the overall outcome of muscle movement. This is examined in a series of phases with Phase I using primitive geometry as a simplistic representation of muscle. Phases II and III add anatomical representations of the shoulder joint with increasing complexity. Two methods of contraction focused on an applied maximal force (Fmax) and prescribed displacement. Further analyses tested the variability of material properties as well as simulated injury scenarios. The results were compared based on displacement, von Mises stress and solve time. As expected, more complex models took longer to solve. It was also supported that applied force is a preferred method of contraction as it allows for antagonistic and synergistic interaction between muscles. The most important result found in these studies was the consistency in the levels of displacement and stress distribution across the three different 3-D representations of muscle. This stability allows for the interchangeability between the three different representations of muscles and will permit researchers to choose to use either a bulk, central line of action or a spline model. The determination of which 3-D representation to use lies in what physical phenomenon (motion, injury etc.) is being simulated.

APA, Harvard, Vancouver, ISO, and other styles

17

Kalezic, Nebojsa. "Autonomic reactivity in muscle pain : clinical and experimental assessment." Doctoral thesis, Umeå universitet, Kirurgisk och perioperativ vetenskap, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-919.

Full text

Abstract:

There are numerous indications of possible involvement of the autonomic nervous system in the genesis of chronic pain. The possibility exists that sympathetic activation is related to motor dysfunction and changes in sensory processing, which have otherwise been implicated in musculoskeletal disorders. The primary aim of the thesis has been to investigate autonomic regulation at rest and in response to laboratory tests of autonomic function in subjects suffering from chronic pain in different localisations (lower back, neck-shoulder and neck-jaw), as well as to study the relations between autonomic regulation, proprioceptive acuity and clinical data. Secondary aim has been to assess autonomic regulation in fit, pain-free subjects in response to experimentally induced pain and in occupationally relevant settings. A total of 194 subjects suffering from chronic pain participated [low back pain (LBP) n=93; non-traumatic neck pain (NT) n=40, Whiplash associated disorder (WAD) n=40, Whiplash with temporomandibular dysfunction (WADj) n=21]. Each chronic pain group was subjected to a battery of autonomic function tests combining cognitive (Stroop Colour-Word conflict tests), physical (handgrip), sensory (unpleasant sound) and motor tasks (chewing tests) as well as the activation of reflex pathways (paced breathing and the orthostatic test) and compared to an age- and gender balanced control group. Autonomic regulation was also assessed in exposure to experimentally induced muscle pain in healthy subjects (n=24) in order to describe acute pain reaction. Further assessment was carried out during monotonous repetitive work and dynamic work in healthy subjects (n=10) and in a three-day monitoring of ambulance personnel (n=26) in occupational settings. Autonomic regulation was evaluated using cardiovascular (heart rate and heart rate variability, local blood flow and blood pressure), respiratory (breathing rate) electrodermal (skin conductance), muscular (trapezius and masseter EMG) and biochemical (insulin, cortisol, catecholamines) variables. Proprioceptive acuity was assessed using active-active repositioning tests. Pain levels were assessed using Visual-analogue or Numerical Rating scales. General health was evaluated through the Short-Form SF-36 Health Related Quality of Life questionnaire and Self-Efficacy Score questionnaires, whereas dysfunction was evaluated using the Oswestry Low Back Pain questionnaire, Pain Disability and Neck Disability Index questionnaires, the McKenzie evaluation and primary healthcare diagnoses. Self-reports of pain, stress and exertion were acquired prior to, during and post-testing. Chronic pain subjects were characterised by increased sympathetic and decreased parasympathetic activity as reflected in heart rate (LBP, WAD, WADj), heart rate variability (LBP, WAD, WADj), blood pressure (WADj) and electrodermal activity (LBP). In general, WAD showed more pain and dysfunction than NT, with lower self-efficacy and health-related quality of life. Differential reactivity was observed only in WAD, with increased responsiveness to sensory stimuli (heart rate variability, electrodermal activity), and motor tasks (heart rate) and a decreased response to cognitive challenge (heart rate variability, electrodermal activity). A significant part of WADj subjects showed sensorimotor impairment and low endurance in chewing tests, concomitant with a cardiovascular response that correlated with pain levels. Proprioceptive acuity was not found to be impaired among subjects suffering from chronic pain, and there were no indications of significant individual response specificity. Response to experimentally induced muscle pain in healthy subjects was also characterised by a prominent cardiovascular component. In simulated occupational settings autonomic activation and transient insulin resistance were detected in healthy subjects following monotonous repetitive work, with no similar effects following dynamic exercise. Modest deviations in circadian heart rate variability patterns during workdays were detected in ambulance personnel reporting more pronounced musculoskeletal symptoms, with no such effects on work-free days. Autonomic balance observed in chronic pain subjects was characterised by a trend towards increased sympathetic activity in comparison with pain-free controls. Moderate signs of affected reactivity to autonomic function tests were observed in patients with WAD, however no specific reaction patterns have been observed in any chronic pain group. Correspondence between the intensity of pain and autonomic activity was observed in acute pain and in chronic pain groups characterised by higher pain levels. As indicated by autonomic and neurohormonal changes in the recovery from real and simulated work, further studies with physiological monitoring of the effects of work-related stress are warranted for better understanding of the mechanism of musculoskeletal disorders.

APA, Harvard, Vancouver, ISO, and other styles

18

Karst, Gregory Mark. "Multijoint arm movements: Predictions and observations regarding initial muscle activity at the shoulder and elbow." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184920.

Full text

Abstract:

Understanding the control strategies that underlie multijoint limb movements is important to researchers in motor control, robotics, and medicine. Due to dynamic interactions between limb segments, choosing appropriate muscle activations for initiating multijoint arm movements is a complex problem, and the rules by which the nervous system makes such choices are not yet understood. The aim of the dissertation studies was to evaluate some proposed initiation rules based on their ability to correctly predict which shoulder and elbow muscles initiated planar, two-joint arm movements in various directions. Kinematic and electromyographic data were collected from thirteen subjects during pointing movements involving shoulder and elbow rotations in the horizontal plane. One of the rules tested, which is based on statics, predicted that the initial muscle activity at each joint is chosen such that the hand exerts an initial force in the direction of the target, while another rule, based on dynamics, predicted initial muscle activity such that the initial acceleration of the hand is directed toward the target. For both rules, the data contradict the predicted initial shoulder muscle activity for certain movement directions. Moreover, the effects of added inertial loads predicted by the latter rule were not observed when a 1.8 kg mass was added to the limb. The results indicated, however, that empirically derived rules, based on ψ, the target direction relative to the distal segment, could predict which muscles would be chosen to initiate movement in a given direction. Furthermore, the relative timing and magnitude of initial muscle activity at the shoulder and elbow varied systematically with ψ. Thus, the target direction relative to the forearm may be an important variable in determining initial muscle activations for multijoint arm movements. These findings suggest a control scheme for movement initiation in which simple rules suffice to launch the hand in the approximate direction of the target by first specifying a basic motor output pattern, then modulating the relative timing and magnitude of that pattern.

APA, Harvard, Vancouver, ISO, and other styles

19

Chang, Li-Shan. "Effects of Stroke Patterns on Shoulder Joint Kinematics and Electromyography in Wheelchair Propulsion." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/kin_health_diss/3.

Full text

Abstract:

The purpose of this dissertation was to analyze shoulder joint kinematics and electromyographic activities of wheelchair propulsion between two stroke patterns. Twenty physical therapy students (14 females and 6 males, age 27.4 ± 5.9 years, body mass 64.41 ± 9.37 Kg and body height 169.32 ± 9.12 cm) participated. Eleven reflective markers were placed on thorax and right scapula, humerus, third metacarpophalangeal joint and wheelchair axle. Surface electrodes were placed on right pectoralis major, anterior and posterior deltoids, infraspinatus, middle trapezius, biceps brachialis long head and triceps brachialis. Participants propelled a standard wheelchair on a stationary roller system at 0.9 m/s and 1.8 m/s with semicircular (SC) and single loop (SL) stroke patterns for 20 seconds. Three-dimensional body movement and muscle activities were recorded at 100 and 1000 Hz, respectively. All data were compared for differences between two patterns and two speeds using 2-way repeated measures ANOVA (α < .05). Results showed longer drive phase and shorter recovery phase in SC when compared to SL, with no difference found on cycle time. Smaller release angles in SC caused longer angle ranges of hand contact on the pushrim while initial contact angles did not change. During drive phase, smaller scapular protraction range of motion (ROM) was found in SC. Shoulder abduction in drive phase was larger in terms of the maximal angle and ROM. In the recovery phase, minimal scapular tilting, protraction, and shoulder abduction and internal rotation were larger in SC when compared to SL pattern. Shoulder linear velocities and accelerations were higher in both phases for abduction/adduction and flexion/extension in SC. For SC pattern, pectorals major and middle trapezius showed lower activities during drive phase while posterior deltoid and triceps showed higher activities during both phases when compared to SL. Although posterior deltoid and triceps muscles work harder in SC pattern, longer drive phase and lower muscle activities in pectorals major and middle trapezius during the drive phase may make SC the better stroke pattern in wheelchair propulsion when compared to SL.

APA, Harvard, Vancouver, ISO, and other styles

20

Sherman, Kim Michelle. "An Evaluation of Fatigue and Performance Changes During Intermittent Overhead Work." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9657.

Full text

Abstract:

This study examined changes in task performance during performance of simulated overhead assembly task. The study objectives were to better understand the relationship between fatigue development during overhead work and task performance. This relationship is important, considering that performance changes, or decreases in task quality, have the potential for justifying and driving ergonomic changes that can help to improve worker safety. Sixteen people participated in eight experimental conditions (two levels of duty cycles, two work heights, and two hand positions). Four dependent measures based on endurance, subjective, objective, and physiological fatigue were used to quantify shoulder fatigue and were collected during the experiment. An overhead work task required participants to use a hand tool to strike targets at two reach distances above their head. Task performance was measured as a function of the closeness to the target center and the ability to apply a consistent force throughout the experiment. Data collected in this experiment is intended to provide a research basis for creating design guidelines that will help maximize efficiency and quality while reducing the likelihood of developing shoulder fatigue.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

21

Yassierli, Yassierli. "Muscle Fatigue during Isometric and Dynamic Efforts in Shoulder Abduction and Torso Extension: Age Effects and Alternative Electromyographic Measures." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/29509.

Full text

Abstract:

Aging has been associated with numerous changes in the neuromuscular system. Age effects on muscular performance, however, have been addressed only in limited contexts in earlier research. The present work was conducted primarily to investigate age-related effects on muscle capacity (fatigue and endurance) during isometric and dynamic efforts. This work was also motivated by current theories on muscle fatigue as a potential risk factor for musculoskeletal disorders and recent demographic projections indicating a substantial increase of older adults in the working population. Four main experiments were conducted to investigate development of muscle fatigue during isometric and intermittent efforts in shoulder abduction and torso extension at different contraction levels. Two age groups were involved (n=24 in each), representing the beginning and end of working life. Findings from this study demonstrated that the older group exhibited slower progressions of fatigue, though the age effect was more consistent for the shoulder than the torso muscles. This implied a muscle dependency of the influence of age on fatigue. Several interaction effects of age and effort level were also observed, suggesting that both task and individual factors should be considered simultaneously in job design. The present investigation also sought to develop alternative electromyography (EMG)-based fatigue parameters for low-level isometric and dynamic contractions, two areas in which improvements are needed in the sensitivity and reliability of existing EMG indices. Several alternative EMG indices were introduced, derived from logarithmic transformation of EMG power spectra, fractal analysis, and parameter estimation based on a Poisson distribution. Potential utility of several of these alternative measures was demonstrated for assessment of muscle fatigue.
Ph. D.

APA, Harvard, Vancouver, ISO, and other styles

22

Lucas, Karen Rae, and karen lucas@rmit edu au. "The Effects of Latent Myofascial Trigger Points on Muscle Activation Patterns During Scapular Plane Elevation." RMIT University. Health Sciences, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080408.144402.

Full text

Abstract:

Despite a paucity of experimental evidence, clinical opinion remains that though LTrPs allow pain-free movement, they are primarily associated with deleterious motor effects and occur commonly in 'healthy' muscles. The primary aim of this study was to investigate the effects of LTrPs on the muscle activation patterns (MAPs) of key shoulder girdle muscles during scapular plane elevation of the arm in the unloaded, loaded and fatigued states. In connection with the main aim, a preliminary study was carried out to examine the frequency with which LTrPs occur in the scapular positioning muscles in a group of normal subjects. After establishing intra-examiner reliability for the clinical examination process, 154 healthy subjects volunteered to be screened for normal shoulder girdle function, then undergo a physical examination for LTrPs in the trapezius, rhomboids, levator scapulae, serratus anterior and the pectoralis minor muscles bilaterally. Of these 'healthy' subjects, 89.8% had at least one LTrP in the scapular positioning muscles (mean=10.65 ± 6.8, range=1-27), with serratus anterior and upper trapezius harbouring the most LTrPs on average (2.46 ± 1.8 and 2.36 ± 1.3 respectively). Consistent with clinical opinion, this study found that LTrPs occur commonly in the scapular positioning muscles. To investigate the motor effects of LTrPs, surface electromyography (sEMG) was used to measure the timing of muscle activation of the upper and lower trapezius and serratus anterior (upward scapular rotators), the infraspinatus (rotator cuff) and middle deltoid (arm abductor). These studies found that LTrPs housed in the scapular upward rotator muscles affected the timing of activation and increased the variability of the activation times of this muscle group and were also associated with altered timing of activation in the functionally related but LTrP-free infraspinatus and middle deltoid. Compared with the control group (all muscles LTrP-free), the MAPs of the LTrP group appeared to be sub-optimal, particularly in relation to preserving the subacromial space and the loading of the rotator cuff muscles. After the initial sEMG evaluations, the LTrP subjects were randomly assigned to one of two interventions: superficial dry needling (SDN) followed by post-isometric relaxation (PIR) stretching to remove LTrP s or sham ultrasound, to act as a placebo treatment where LTrPs remained. Where LTrPs were removed, a subsequent sEMG evaluation found MAPs to be similar to the control group in most of the experimental conditions investigated. Of particular note, when LTrPs had been treated and the subjects repeated the fatiguing protocol, the resultant MAP showed no significant difference with that of the control group in the rested state, suggesting treating LTrPs was associated with an improved response to fatigue induced by repetitive overhead movements. In conclusion, the findings indicate that LTrPs commonly occur in scapular positioning muscles and have deleterious effects on MAPs employed to perform scapular plane elevation and thus affect motor control mechanisms. Treating LTrPs with SDN and PIR stretching increases pressure-pain thresholds, removes associated taut bands and at least transiently optimises the MAP during scapular plane elevation. Discussion includes possible neuromuscular pathophysiology that might explain these results.

APA, Harvard, Vancouver, ISO, and other styles

23

Galloway, James Coleman. "Muscle torque-total torque relationships at the shoulder and elbow: Rules for initiating multijoint arm movements." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282845.

Full text

Abstract:

One concept central to theories of multijoint control concerns the selection of muscles for the appropriate joint motion. For multijoint movements, a given muscle torque at an individual joint can lead to flexion, extension, or very little motion, since mechanical effects coming from other segments interact with muscle torque. This study quantified the contribution of muscle torque to initial joint motion for horizontal arm movements throughout the workspace. Previous studies of arm mechanics have been limited to a few movements or have focused on one joint. In contrast, this study reports data for both the shoulder and elbow joints. Moreover, a large number of movements were used for which direction, excursion, and distance were manipulated. Using high speed video recordings and techniques of inverse dynamics, a ratio of muscle torque to total torque was computed for each movement as a measure of contribution of muscle torque to joint acceleration. One consistent finding was that the muscle torque contribution consistently differed between the shoulder and elbow for most of the workspace. At one joint, muscle torque directly contributed to acceleration with negligible interaction torque ('direct' muscle torque contribution), thus the joint appeared to act as the launcher of the arm. At the other joint, both muscle and interaction torques contributed to joint acceleration ('complex' contribution), thus the joint appeared to be responding to mechanical effects from motion of the launcher. This contrast between joints may provide a simplifying feature for multijoint arm control. Specifically, only one of the two joints has complex mechanics, while the other joint, surprisingly, has simplified mechanics similar to a single joint in isolation. Movements in this study also demonstrated a three fold covariance (muscle torque contribution, movement direction, and the relative excursions of the shoulder and elbow) regardless of distance. A covariance of movement features, historically viewed as a confound, may provide a further simplification for arm control by reducing the unknowns; namely, the muscle torque contribution is associated with a resultant direction and joint excursions, or a direction or set of excursions is achieved by the associated muscle torque contribution.

APA, Harvard, Vancouver, ISO, and other styles

24

Eriksson, Anders. "Strenght training and anabolic steroids : a comparative study of the trapezius, a shoulder muscle and the vastus lateralis, a thigh muscle, of strength trained athletes." Doctoral thesis, Umeå : Umeå universitet, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-869.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Zetterberg, Camilla. "The impact of visually demanding near work on neck/shoulder discomfort and trapezius muscle activity : Laboratory studies." Doctoral thesis, Uppsala universitet, Arbets- och miljömedicin, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-281413.

Full text

Abstract:

Introduction: Musculoskeletal discomfort in the neck and shoulders is common among workers performing visually demanding near work, e.g., on a computer screen, and sustained low-level muscle activity during such work can lead to work-related pain. The relationships between visual demands and muscle activity and discomfort in the neck/shoulder region are at present unclear. Aim: The aims of this thesis were to determine whether neck/shoulder discomfort and trapezius muscle activity increases during visually demanding experimental near work, and to investigate whether eye-lens accommodation is a mediating mechanism behind increased trapezius muscle activity. Methods: The four papers included are based on two experiments with different visually demanding near work tasks (duration 5 and 7 min). Trial lenses of different diopters were used to manipulate the visual demands (i.e., induce more or less accommodation) and thereby create different viewing conditions. Monocular viewing, which does not require active convergence, was used to examine the isolated effect of accommodation. Eye-lens accommodation and trapezius muscle activity were measured continuously during the visual tasks, and in one experiment the participants rated their eye and neck/shoulder discomfort at baseline and after each visual task. Results: Neck/shoulder discomfort and trapezius muscle activity increased during the visually demanding near work and participants experiencing a greater increase in eye discomfort (compared with baseline) also developed more neck/shoulder discomfort with time. There were no significant differences in muscle activity among the viewing conditions, and no effect of isolated accommodation response within the monocular viewing conditions. Conclusion: These findings indicate that accommodation per se is unlikely to mediate trapezius muscle activity. Instead, the increase in trapezius muscle activity observed here may be due to a combination of high visual attention and enhanced requirement for eye-neck (head) stabilisation. Since these results suggest that neck/shoulder discomfort may aggravate with time when the visual demands are high, it is important to provide good visual conditions in connection with visually demanding occupations.
Introduktion: Muskelrelaterade besvär i nack- och skulderområdet är vanligt förekommande, framförallt hos individer som utför synkrävande datorarbete. En orsak till sådana besvär anses vara långvarig lågintensiv aktivitet i dessa muskler. Det är i dagsläget oklart om de belastningar som synsystemet utsätts för vid synkrävande arbete bidrar till ökad muskelaktivitet i nack/skulderregionen. Syfte: Syftet var att undersöka om experimentellt synkrävande närarbete påverkar muskelaktivitet och besvär i nack/skulderregionen, och att undersöka om aktivitet i trapezius muskeln (kappmuskeln) påverkas av ögats ackommodation, d.v.s. när linsens brytkraft förändras för att se skarpt på nära håll. Metod: De fyra delstudierna baseras på två laborativa experiment där försökspersoner (66 respektive 26 stycken) genomförde olika synkrävande uppgifter (fem och sju minuter långa). För att göra synuppgifterna mer eller mindre ansträngande för synsystemet användes linser med olika grad av brytkraft (dioptrier). Dessutom, eftersom monokulärt seende inte kräver aktiv konvergens, genomfördes tre av de fyra synuppgifterna i ena experimentet med ett öga för att undersöka den enskilda effekten av ackommodation. En autorefraktor mätte ögats ackommodation under synuppgifterna och aktiviteten i trapeziusmuskeln registreades kontinuerligt med elektromyografi (EMG). I samband med det ena experimentet skattade deltagarna sina upplevda ögon- och nack/skulderbesvär, både före experimentet (baslinje) och efter varje synuppgift. Resultat: Det synkrävande arbetet ökade både de självskattade nack/skulderbesvären och muskelaktiviteten i trapezius. De personer som upplevde en högre ökning av ögonbesvär (i förhållande till baslinjen), rapporterade också mer nack/skulderbesvär över tid. Det var varken någon signifikant skillnad i grad av muskelaktivitet mellan synuppgifterna, eller något signifikant samband mellan monokulär ackommodation och muskelaktivitet. Slutsats: Resultaten indikerar att ögats ackommodation, i sig, inte påverkar muskelaktiviteten i trapezius. Ökad muskelaktivitet i nack/skulderregionen i anslutning till synkrävande arbete kan istället bero på en kombination av höga krav på visuell uppmärksamhet och ett ökat behov av att stabilisera ögonen (huvudet) i förhållande till objektet i fokus (t.ex. texten på en bildskärm). Eftersom resultaten tyder på att synkrävande närarbete leder till ökade besvär i nack/skuldraregionen över tid, är det viktigt att utforma arbetsplatser och synkrävande arbetsuppgifter (t.ex. vid datorn) på ett sätt som främjar visuell hälsa.

APA, Harvard, Vancouver, ISO, and other styles

26

Bernal, Covarrubias Rafael Ricardo. "Biomechanical Assessment of a Human Joint under Natural and Clinically Modified Conditions: The Shoulder." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/556975.

Full text

Abstract:

Unbalanced muscle forces in the shoulder joint may lead to functional impairment in the setting of rotator cuff tear and progressive arthritis in cuff tear arthropathy. A model, which predicts muscle forces for common shoulder movements, could be used to help in treatment decision-making and in improving the design of total shoulder prosthesis. Unfortunately, the shoulder has many muscles that overlap in function leading to an indeterminate system. A finite element model employing an optimization algorithm could be used to reduce the number of degrees of freedom and predict loading of the glenohumeral joint. The goal of this study was to develop an anatomically and physiologically correct computational model of the glenohumeral joint. This model was applied to: 1) estimate the force in each muscle during the standard glenohumeral motions (flexion/extension, abduction/adduction and internal/ external rotation), and 2) determine stress concentrations within the scapula during these motions. These goals were realized through the following steps: First, a three dimensional bone reconstruction was performed using computed tomography (CT) scan data. This allowed for a precise anatomical representation of the bony components. Then muscle lever arms were estimated based on the reconstructed bones using computer-aided design software. The origins, insertions, and muscle paths were obtained from the literature. This model was then applied to estimate the forces within each of the muscles that are necessary to stabilize the joint at a fixed position. Last, finite element analysis of the scapula was performed to study the stress concentrations. These were identified and related to the morphology of the bone. A force estimation algorithm was then developed to determine the necessary muscle force distribution. This algorithm was based on an applied external moment at the joint, and the appropriate selection of muscles that could withstand it, ensuring stability, while keeping the reaction force at a minimum. This method offered an acceptable solution to the indeterminate problem, a unique solution was found for each shoulder motion. The model was then applied to determine the stress concentration within various regions of the scapula for each of the shoulder motions. The rotator cuff was found to act as the main stabilizer under rotation, and had a significant stabilizing role under flexion and abduction. The finite element model of the shoulder that was developed can be used to gain a better understanding of the load transfer mechanisms within the glenohumeral joint and the impact of muscle forces on scapular morphology. This information can then be used to assist with treatment decision-making for rotator cuff tears and with the design of new implants for total shoulder arthroplasty.

APA, Harvard, Vancouver, ISO, and other styles

27

Rissén, Dag. "Repetitive and monotonous work among women : Psychophysiological and subjective stress reactions, muscle activity and neck and shoulder pain." Doctoral thesis, Stockholm University, Department of Psychology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-1234.

Full text

Abstract:

Repetitive and monotonous work is frequently associated with neck and shoulder pain and negative psychosocial factors inducing stress reactions. The present thesis concerns the relations between psychophysiological and subjective stress reactions, muscle activity measured by surface electromyography (SEMG) in the trapezius muscle, and neck and shoulder pain in women performing repetitive and monotonous work. In Study I cardiovascular and subjective stress reactions were investigated during computer work in a laboratory setting. The findings indicated that heart rate variability is a more sensitive and selective measure of mental stress compared with blood pressure recordings. Study II explored the relations between stress reactions and muscle activity during supermarket work. The results showed that perceived negative stress reactions may have a specific influence on muscle activity in the neck and shoulder region, which can be of importance for work-related musculoskeletal disorders in repetitive and monotonous work. In Study III the association between SEMG activity patterns and neck and shoulder pain was investigated during cash register work. It was found that pain-afflicted women had a different muscle activation pattern (more static, more co-contraction, less muscle rest) compared with pain-free women. Study IV was a follow-up study evaluating the introduction of job rotation among female cashiers. The results indicated positive effects on diastolic blood pressure, muscle activity, and partly on neck and shoulder pain, although perceived stress was unchanged. It was concluded that job rotation seems to have a limited effect on chronic neck and shoulder pain, but may be an effective preventive measure. The empirical findings are particularly relevant for women who, compared with men, more often perform repetitive and monotonous work and are also more often affected by neck and shoulder pain.

APA, Harvard, Vancouver, ISO, and other styles

28

Rissén, Dag. "Repetitive and monotonous work among women : psychophysiological and subjective stress reactions, muscle activity and neck and shoulder pain /." Stockholm : Department of Psychology, Stockholm University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-1234.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Politti, Fabiano. "A eletromiografia como ferramenta de estudo da ação da auriculoacunputura." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317514.

Full text

Abstract:

Orientador: Evanisi Teresa Palomari
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-10T18:15:43Z (GMT). No. of bitstreams: 1 Politti_Fabiano_D.pdf: 862982 bytes, checksum: e7f128f64db3385d3565211be8cbaf2e (MD5) Previous issue date: 2007
Resumo: Os avanços nos conhecimentos em neurofisiologia permitiram definir que a acupuntura é um método de estimulação neural periférica, que provoca respostas reflexas, locais e sistêmicas. Portanto, o objetivo deste trabalho foi verificar se a eletromiografia de superfície pode ser utilizada como ferramenta de estudo da ação da acupuntura auricular (AA) sobre o músculo estriado esquelético e se a AA interfere na freqüência do sinal eletromiográfico (EMG) do músculo. Assim, foi analisado a amplitude sinal EMG normalizado das porções clavicular, acromial e escapular do músculo deltóide e da porção descendente do músculo trapézio com 20%, 40% e 60% da contração voluntária máxima, em 15 indivíduos voluntários saudáveis, após o tratamento com AA. A freqüência média do sinal EMG foi obtida do músculo trapézio descendente. Na coleta dos dados foi utilizado um eletromiógrafo de 8 canais com freqüência de amostragem de 1.33 kHz. Para verificar a diferenças entre os valores em RMS (root mean square) obtidos por meio de janela móvel de 200 ms, foi utilizado o teste de Friedman. Nos casos em que os resultados se apresentaram significantes o teste de Wilcoxon foi utilizado para comparações múltiplas. O nível de significância adotado foi de p < 0,05 e para as comparações Nesse estudo concluiu-se que a eletromiografia de superfície pode ser utilizada como ferramenta na análise dos efeitos da AA sobre a atividade do músculo e que o método utilizado para gravar o sinal EMG pode influenciar os resultados. Além disso, a AA pode atuar como mecanismo modulador da atividade do músculo, determinando o numero de unidades motoras recrutadas e a sua média da freqüência de disparo de acordo com o nível de força adotada durante uma tarefa realizada com contração isométrica
Abstract: The advancement of knowledge in neurophysiology has demonstrated that acupuncture is a method of peripheral neural stimulation that promotes local and systemic reflexive responses. The purpose of this study was to determine if surface electromyography can be used as a tool to study the action of auricular acupuncture (AA) on the striated skeletal muscle and if auricular acupuncture interferes with the frequency of the EMG signal of the muscle. The EMG amplitudes of the anterior, middle and posterior deltoid muscle and the upper trapezium muscle with 20%, 40% and 60% of maximal voluntary contraction (MVC) of 15 healthy volunteers, were analyzed after the individuals were submitted to the AA treatment. The median frequency (MF) surface electromyography (EMG) recordings were obtained from the upper trapezius muscle. The nonparametric Friedman test was used to compare Root Mean Square (RMS) values estimated by using a 200 ms moving window. Significant results were further analysed using the Wilcoxon signed rank test. In this exploratory study, the level of significance of each comparison was set to p < 0,05. It was concluded in this study that a surface EMG can be used as a tool to investigate possible alterations of electrical activity in muscles after AA, however there is still a lack of adequate methodology for its use in this type of study, being that the method used to record the EMG signal can also influence the results. The AA peripheral stimulus can act as a modulator mechanism of muscle activity, as a result of the number of motor units recruited and their mean discharge frequency of excitation according to the level of force adopted during a task carried out with isometric contraction
Doutorado
Anatomia
Doutor em Biologia Celular e Estrutural

APA, Harvard, Vancouver, ISO, and other styles

30

Kablan, Nilufer. "Effects Of Different Joint Positions, Rotator Cuff Muscle Fatigue And Experience On Shoulder Proprioceptive Sense Among Male Volleyball Players." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12604772/index.pdf.

Full text

Abstract:

The aim of this study was to evaluate the effect of different joint positions, rotator cuff muscle fatigue and experience on shoulder proprioceptive sense among male volleyball players. The participants of the study were 20 experienced (Mage= 20.7 &
#61617
2.8) and 20 inexperienced (Mage= 17.1 &
#61617
1.0) male volleyball players being members of first league volleyball teams. Measurements were made by Biodex System 3 pro (Biodex Medical Systems, Inc., New York, USA) and only dominant extremities were assessed. Shoulder proprioceptive sense was determined by measuring participant&rsquo
s perception of joint position sense with the joint at 90&
#61616
abduction, external rotation and 90&
#61616
abduction, neutral rotation. Participants were tested at a speed of 2 deg/s before and after exercising on an isokinetic testing machine until fatigued. Fatigue protocol was practiced at 60 deg/s and it was terminated when the internal rotation maximal peak torque decreased by 50%. There was significant difference between proprioceptive sense of inexperienced volleyball players at 10&
#61616
-20&
#61616
(p<
.01) and 15&
#61616
-20&
#61616
(p<
.05) in external rotation before fatigue. The difference between before and after fatigue proprioceptive sense of experienced volleyball players at 20&
#61616
(p<
.05) was found statistically significant, whereas the significant difference was observed between before and after fatigue proprioceptive sense of inexperienced players at 10&
#61616
(p<
.01) and 15&
#61616
(p<
.05) in internal rotation. It was concluded that the effect of fatigue on proprioceptive sense is related with experience, but experience itself had no effect on proprioceptive sense.

APA, Harvard, Vancouver, ISO, and other styles

31

Holmemo, Ingvild Kiil. "The Relation between Stress, Muscle Activity, and Shoulder/Neck Pain : a Long-Term Field Study on Health Care Workers." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bevegelsesvitenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-13156.

Full text

Abstract:

Background: Shoulder and neck pain (SNP) is one of the main causes for sick-leave, and the high prevalence affects occupations with both high, moderate and low workloads. At present, the knowledge about pain mechanisms in occupations with low physical workload is still limited. The main purpose of this study was to investigate whether perceived work stress during the workday is related to trapezius muscle activity. A second objective was to investiagte whether trapezius activity differs between individuals with long-term SNP. Methods: Twenty-seven female health care workers participated. Surface electromyography (sEMG) was recorded from the trapezius muscle throughout the workday. Simultaneous inclinometer recordings of the thigh was used to identify periods with sitting, standing, and walking. SNP and stress were recorded by visual analogue scale and physical fatigue by Borgs scale every hour throughout the workday. An index for long-term SNP was also calculated. Findings: Two main comparisons were performed: A between group comparison where sEMG in pain-afflicted workers was compared to sEMG recorded from pain-free workers, and an intra-individual comparison where sEMG in periods of high stress was compared to periods of low stress. In the analyses of the sEMG activity pattern, the focus was on median amplitude and rest time defined as activity < 0.5% of the maximal sEMG response. Overall, there was no evidence of a difference in sEMG activity between pain-free and pain-afflicted workers. Neither did sEMG activity differ between periods with high vs. low stress. Interpretation: The current study does not support the hypothesis that SNP is related to stress-induced low level muscle activity. Further research is needed to reveal the relation between stress, muscle activity and SNP, and the mechanisms behind.

APA, Harvard, Vancouver, ISO, and other styles

32

Bjerkefors, Anna. "Performance and trainability in paraplegics : motor function, shoulder muscle strength and sitting balance before and after kayak ergometer training /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-981-5/.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Camarini, Paula Maria Ferreira. "Influência do alongamento da musculatura do aspecto anterior do ombro na cinemática escapular." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/17/17152/tde-21092016-155326/.

Full text

Abstract:

A movimentação escapular é de grande importância para o funcionamento adequado do ombro. Indivíduos com disfunção no ombro apresentam uma diminuição da rotação superior e da inclinação posterior e um aumento da rotação interna da escápula durante a elevação do braço. Vários fatores estão envolvidos na alteração da cinemática escapular. Um deles é o encurtamento do músculo peitoral menor, sendo que indivíduos com comprimento de repouso reduzido desse músculo apresentaram diminuição da inclinação posterior e aumento da rotação interna da escápula durante o movimento do braço. Tal alteração cinemática é similar à apresentada por sujeitos com disfunção do ombro e pode ser um fator de risco para o desenvolvimento de sintomas. Portanto, o objetivo desse estudo foi avaliar a influência de um programa de alongamento da musculatura do aspecto anterior do ombro na cinemática escapular. O sistema eletromagnético de aquisição de dados foi utilizado para avaliar a cinemática escapular pré e pós um programa de alongamento da musculatura do aspecto anterior do ombro. Esse programa foi composto por três repetições de três exercícios de 30 segundos e teve duração de quatro semanas. O modelo linear de efeitos mistos foi utilizado para análise estatística das comparações entre as avaliações pré e pós-programa de alongamento. Não houve diferença estatisticamente significativa entre as avaliações antes e após a intervenção do estudo. Tal resultado sugere que o alongamento sozinho não é capaz de alterar a movimentação escapular, mas pode ser que contribua para o aumento da inclinação posterior se associado com outras intervenções.
The adequate scapular motion is very important to the shoulders function. Subjects with shoulder dysfunction present decreased scapular upward rotation and posterior tilt and increased scapular internal rotation during arm elevation. Many mechanisms are involved in scapular kinematics alteration. One of them is the pectoralis minor muscle shortening. Healthy subjects with relative short pectoralis minor resting length presented decreased upward rotation and increased internal rotation when compared with individuals with relative long resting length of this muscle. Hence, the purpose of this study was to evaluate the influence of the anterior shoulder aspect musculature stretching on scapular kinematics. The electromagnetic tracking device was utilized for kinematics analysis before and after a stretching program of the anterior shoulder aspect musculature. This program was composed by three repetition of three 30 seconds exercises and lasted for four weeks. The linear mixed effects model was used for statistical analysis of the comparison between pre and post stretching program evaluations. There was not a statistically significant difference between the pre and post intervention evaluations, Such outcome suggest that stretching alone cannot alter the scapular motion, but may contribute to the increase in posterior tilt if associates with others interventions.

APA, Harvard, Vancouver, ISO, and other styles

34

Maynard, Robert. "The effects of limb speed and limb preference on selected isokinetic strength and power measures during internal and external rotation of the shoulder." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/42059.

Full text

Abstract:

Forty-five males volunteered to serve as subjects to investigate the effects of limb velocity and limb preference on peak torque/body weight (PTBW), torque acceleration energy (TAE), average power (AVP), and endurance ratio (ER) at isokinetic speeds of 60 and 300 degrees/second during internal and external rotation of the shoulder. Standard Cybex warm-up and test protocol were used for both test conditions. Test/retest reliability estimates ranges from r=.60- .70. Repeated Measures ANOVA revealed significant limb speed and limb preference effects on PTBW, TAE, and AVP in both exercise speed or limb preference. The data illustrate a need for an internal/external shoulder rotation normative profile specific to limb speed and limb preference.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

35

Kinder, Jessica Marie. "The Relationship of Hip Muscle Activation and the Incidence of Shoulder Injury in Collegiate Women's Volleyball Athletes: A Pilot Study." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/28776.

Full text

Abstract:

Previous studies have indicated weak hip muscle activation in baseball pitchers leads to an increased incidence of shoulder injuries. This relationship, however, has not been explored in other overhead athletes, such as volleyball players. Surface electromyography (EMG) was used to evaluate each participant?s muscle activation during five dynamic activities. Dynamic activity was normalized according to MMTs for the rectus femoris, biceps femoris, gluteus maximus, and gluteus medius. The GMed during the eccentric box jump was statistically significant for position where setters showed the greatest activation and defensive players the least. The GMax during the single-leg deadlift was statistically significant for position where setters showed the greatest activation and defensive players the least. The hamstring showed statistically significant activation during the eccentric box jump where defensive players showed the highest activation and setters the least. The results should serve as a pilot study for future research due to the limited population.

APA, Harvard, Vancouver, ISO, and other styles

36

Costantini, Oren. "SERRATUS ANTERIOR MUSCLE FATIGUE EFFECTS ON SCAPULAR KINEMATICS." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1325219873.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Minozzo, Felipe. "Equilíbrio de força muscular e retardo eletromecânico na articulação do ombro entre atletas de diferentes modalidades esportivas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/172501.

Full text

Abstract:

O objetivo deste estudo foi avaliar e comparar o equilíbrio de força muscular e o tempo de retardo eletromecânico na articulação do ombro entre atletas de diferentes modalidades esportivas, os quais utilizam predominantemente rotações internas e externas de ombro durante as suas práticas esportivas. Fizeram parte do estudo 41 sujeitos do sexo masculino, sendo 15 atletas profissionais de Voleibol (24,07 ± 5,13 anos; 91,60 ± 11,67 kg; 198,47 ± 5,90 cm), 14 atletas profissionais de Judô (26,64 ± 7,30 anos; 87,36 ± 15,20 kg; 178,07 ± 6,90 cm) e 12 atletas universitários de Handebol (23,17 ± 4,70 anos; 84,75 ± 13,50 kg; 182,08 ± 6,20 cm). Para a mensuração de força máxima, de diferença contralateral (i.e. lados direito vs. esquerdo) e para o cálculo das razões entre rotação interna e externa de ombro, os participantes realizaram testes de dinamometria isocinética em condições isométricas e isocinéticas. Durante os testes isométricos foi realizada a coleta do sinal eletromiográfico dos músculos peitoral maior e infraespinal, o que possibilitou o cálculo do retardo eletromecânico. Os resultados demonstram que atletas de Judô possuem força isométrica de rotação interna de ombro significativamente (p<0,01) maior quando comparados com atletas de Voleibol e de Handebol. Atletas de Judô apresentam valores de razão agonista/antagonista isométrica de membro direito significativamente (p<0,03) inferiores aos grupos Voleibol e Handebol, bem como significativamente (p<0,01) inferiores ao grupo Voleibol em relação ao membro esquerdo O tempo de retardo eletromecânico apresentou diferenças entre os grupos somente na rotação externa, em que o grupo Voleibol apresentou valores do membro direito significativamente (p<0,01) mais curtos quando comparados com o grupo Handebol e valores de membro esquerdo significativamente (p<0,01) mais curtos quando comparados com os grupos Handebol e Judô. Picos de torque isocinéticos apresentaram diferença somente para rotação interna de membro direito, em que o grupo Judô apresentou valores significativamente (p<0,001) maiores quando comparados com o grupo Voleibol. Já para membro esquerdo, detectou-se diferença significativa (p<0,01) no ângulo de pico de torque de rotação interna de membro esquerdo entre o grupo Judô e Handebol. Os resultados do estudo permitem concluir que a prática de cada modalidade esportiva avaliada neste estudo promoveu adaptação dos músculos do ombro, de acordo com a demanda da modalidade esportiva. Assim, atletas de Judô necessitam realizar reforço dos músculos rotadores externos do ombro, tanto concêntrica quanto excentricamente, visto o desequilíbrio muscular causado pela especificidade da modalidade. Por outro lado, atletas de Voleibol apresentam satisfatório equilíbrio muscular na articulação do ombro por conta de altos níveis de força excêntrica de rotação externa exigidos na prática deste esporte; além disso, os curtos períodos de tempo de retardo eletromecânico apresentados por estes atletas reforçam a constatação de equilíbrio desta articulação. Atletas de Handebol apresentam satisfatório equilíbrio muscular na articulação do ombro, entretanto apresentam valores altos de retardo eletromecânico, sendo indicado que estes atletas realizem reforço de rotação externa de ombro, sobretudo em velocidade elevada, com o objetivo de diminuir o tempo necessário para ativar estes grupos musculares.
The purpose of this study was to evaluate and compare the muscular balance and the electromechanical delay time of the shoulder joint between athletes of different sports modalities who use predominantly internal and external rotations of the shoulder. The study consisted of a total of 41 male subjects, of whom 15 were professional Volleyball players (n = 15, 24.07 ± 5.13 years, 91.60 ± 11.67 kg, 198.47 ± 5.90 cm), 14 professional Judo athletes (26.64 ± 7.30 years, 87.36 ± 15.20 kg, 178.07 ± 6.90 cm) and 12 university Handball athletes (23.17 ± 4.70 years, 84.75 ± 13.50 kg, 182.08 ± 6.20 cm). To evaluate peak torque, upper limb side-to-side asymmetry and for the calculation of conventional and functional ratios, all subjects performed isokinetic dynamometry tests under isometric and dynamic conditions. During the isomeric tests, the electromyographic signal was collected from the pectoralis major and infraspinal muscles, which allowed the calculation of the electromechanical delay. The results demonstrate that Judo athletes have internal shoulder rotation isometric strength significantly (p<0.01) higher when compared to Volleyball and Handball athletes. Judo athletes presented isometric agonist/antagonist ratio of right limb significantly (p<0.03) lower than the Volleyball and Handball groups, as well as significantly (p<0.01) lower than the Volleyball group in relation to the left limb. The electromechanical delay time presented differences between the groups only in the external shoulder rotation, which the Volleyball group presented significantly lower values of right limb (p<0.01) when compared to the Handball group and left limb times significantly (p<0.01) shorter when compared with the Handball and Judo groups Dynamic peak torque presented difference only for internal shoulder rotation of the right limb, which the Judo group presented values significantly (p<0.001) higher when compared to the Volleyball group. For the left upper limb, a significant difference (p<0.01) was detected in the peak torque angle of internal shoulder rotation between the Judo and Handball groups. The results of the study allow to considering that the practice of each evaluated sports modalities adapts the shoulder of its athletes in different ways. Judo athletes need to perform external shoulder rotation muscular strengthening, both in concentric and eccentric modes due to muscle imbalance caused by the specificity of the modality. Volleyball athletes have reasonable muscle balance in the shoulder joint due to the high levels of eccentric strength of external rotation, in addition the short time periods of electromechanical delay presented by these athletes reinforce even more the balance of this joint. Handball athletes have reasonable muscle balance in the shoulder joint; however, they presented high values of electromechanical delay, so it is indicated that these athletes need to perform muscular strengthening of external rotation of the shoulder in order to reduce the time required to activate these muscles.

APA, Harvard, Vancouver, ISO, and other styles

38

Souza, Patrícia de Moura. "Projeto e desenvolvimento de um aparelho para avaliar a força muscular isométrica dos rotatores do ombro." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-26082003-110321/.

Full text

Abstract:

Os músculos do manguito rotador são os responsáveis pelo movimento de rotação do ombro e representam sítio freqüente de processos patológicos.O desequilíbrio de forças do manguito rotador pode desencadear patologias distintas do ombro ou ser resultado destas. A quantificação da força muscular do manguito rotador com dados precisos, somente é possível com aparelhos de alto custo, longe do alcance da maioria dos profissionais envolvidos com o problema em nosso país. No presente estudo, um aparelho relativamente simples e de baixo custo, capaz de mensurar com precisão a força muscular isométrica de rotação interna e rotação externa do ombro, foi projetado e construído com materiais de fácil obtenção e preço acessível. Ele consiste basicamente de uma plataforma de medição do torque de rotação do ombro acoplada a uma cadeira e adaptável para avaliação bilateral. O aparelho foi projetado para que o indivíduo permaneça sentado durante o teste, com cotovelo fletido a 90 graus e o antebraço apoiado sobre uma superfície plana. Um torquímetro, devidamente calibrado, foi fixado na porção inferior da plataforma, no ponto correspondente ao centro de rotação do ombro. A mudança no comprimento do braço de alavanca foi permitida pela variação na posição de um manípulo para apoio da mão durante os esforços de rotação interna e de rotação externa do ombro. Variações no comprimento do braço de alavanca e na altura da plataforma foram projetadas para adaptarem-se aos braços e antebraços dos indivíduos. O aparelho foi testado em 20 indivíduos saudáveis e demonstrou ser completamente versátil para uso em diversas condições e confiável na produção de informações sobre o torque dos músculos rotadores do ombro.
The rotator cuff muscles are responsible for the rotation movements of the shoulder and frequent site of pathological processes. Rotator cuff muscle power imbalance may unchain or result from distinct shoulder diseases. To date precise quantification of rotator cuff muscle power is only possible with the use of expensive machines, far from the reach of most of the professionals involved with the problem in our country. In the present investigation, a relatively simple and low cost device, able to precisely measuring isometric internal and external rotator muscle power, was developed and built with easily obtainable and low cost materials. It consists basically of a platform for measuring the rotational torque of the shoulder adaptable to both sides of a chair for bilateral evaluation. It was designed for the individual to remain seated while in test, the elbow flexed at 90o and the forearm rested on a flat surface. A properly calibrated torquimeter was adapted to the bottom side of the platform in a point corresponding to the shoulders center of rotation. The moving lever was provided with a handle to be grasped by the individual while doing internal or external efforts with the shoulder. Both platform height and moving lever were made adaptable to individual arm and forearm lengths. The device was tested with 20 healthy individuals and demonstrated to be quite versatile for use in many different conditions and reliable in providing information on the torque of the rotator muscle of the shoulder.

APA, Harvard, Vancouver, ISO, and other styles

39

Takeno, Katsumi. "Neuromuscular Function of the Shoulder Girdle and Upper Extremity Muscles in Individuals with Glenohumeral Labral Repair." University of Toledo / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1596111099423871.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Toledo, Joelly Manhic de. "Avaliação da cinemática tridimensional, atividade eletromiográfica e força de contato e muscular em pessoas com e sem prótese de ombro." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/56115.

Full text

Abstract:

Esta tese está dividida em três estudos. No estudo I desta tese, os objetivos foram descrever a cinemática tridimensional do ombro e determinar a contribuição da articulação escápulotorácica no movimento total de elevação. No estudo II, os objetivos foram descrever a atividade eletromiográfica (EMG) e o percentual de cocontração entre os músculos deltóide médio e redondo maior. No estudo III, o objetivo foi determinar o valor máximo da força de contato gleno-umeral e da força muscular. Quarenta sujeitos participaram dos estudos divididos em três grupos: pacientes com prótese total do ombro (PTO), com prótese reversa (PRO) e um grupo controle. Todos realizaram dois exercícios de reabilitação (flexão e elevação no plano escapular) usando diferentes cargas (sem carga externa, halter de 1kg e resistência elástica). A cinemática do ombro foi registrada por meio de um dispositivo eletromagnético de rastreamento, a atividade EMG foi registrada por meio de um eletromiógrafo de 16 canais e o modelo matemático utilizado foi o Delft Shoulder and Elbow Model. As análises estatísticas foram feitas por meio de ANOVAs de dois e três fatores para medidas repetidas. Foi utilizado o teste post hoc de Bonferroni e o nível de significância adotado foi de α < 0,05. Os resultados do estudo I mostram que a escápula contribui mais para o movimento total do ombro em pacientes com prótese em relação aos indivíduos saudáveis e em exercícios realizados com 1 kg e resistência elástica comparados com os exercícios sem carga externa. O ângulo de elevação glenoumeral durante a flexão foi significativamente maior no grupo PTO em comparação ao grupo PRO. O estudo II identificou maior atividade EMG do deltóide médio e posterior no grupo PTO em comparação ao grupo controle e um aumento da atividade EMG do peitoral (parte esternal) no grupo PRO em comparação ao grupo PTO e ao grupo controle. Para os outros músculos (deltóide anterior, redondo maior, peitoral maior - parte clavicular e serrátil anterior) não foram encontradas diferenças significativas entre os grupos. Para todos os músculos, exceto o serrátil anterior, a atividade EMG foi menor nos exercícios sem carga externa quando comparados aos exercícios com 1 kg e resistência elástica. Nenhum efeito principal dos fatores grupo e carga foi encontrado no percentual de cocontração. No estudo III, o grupo controle apresentou maior força de contato gleno-umeral máxima quando comparado ao grupo PTO durante a flexão, mas não foram encontradas diferenças entre os grupos de pacientes nos dois movimentos. A resistência elástica apresentou maiores valores de força de contato gleno-umeral em todos os grupos. O valor máximo da força de todos os músculos analisados variou de 0,32 N a 772 N e o manguito rotador e o deltóide foram os músculos que apresentaram os maiores valores de força em todos os grupos. A presente tese sugere que para uma mesma amplitude de movimento, os pacientes com prótese de ombro apresentarão um movimento escapular maior compensando a perda do movimento gleno-umeral. A cinemática escapular e a atividade EMG destes pacientes foram influenciadas pela implementação de cargas externas, mas não pelo tipo de carga, diferentemente das forças de contato e das forças musculares, nas quais a resistência elástica apresentou maior influência. Além disso, o percentual de cocontração não foi influenciado pelo tipo de prótese e os grupos de pacientes apresentaram menores forças de contato gleno-umeral do que o grupo controle.
This thesis is divided into three studies. In study I, the objectives were to describe shoulder three-dimensional kinematics and to determine the contribution of scapulothoracic motion in total shoulder elevation. In study II, the objectives were to describe the electromyographic activity (EMG) and the percentage of cocontraction between middle deltoid and teres major. In study III, the objective was to determine the maximum glenohumeral contact force and shoulder muscle forces. Forty subjects participated in the studies divided into three groups: patients with total shoulder prosthesis (TSP), patients with reverse shoulder prosthesis (RSP) and a control group. All patients realized two rehabilitation exercises (anteflexion and elevation in the scapular plane) using different loads (without external load, 1 kg dumbbell and elastic resistance). Shoulder kinematics was recorded by means of an electromagnetic tracking device, the EMG activity was recorded through a 16-channel EMG system and the Delft Shoulder and Elbow Model was used. Statistical analyses were performed by means of repeated measures ANOVAs. The Bonferroni post hoc test was used and the adopted significance level was α <0.05. Results of study I showed that the scapula contributes more to the total movement of the shoulder in patients with prosthesis compared to healthy subjects and in exercises performed with 1 kg and elastic resistance compared to exercises without external load. The glenohumeral elevation angle during anteflexion was significantly higher in the TSP group compared to the RSP. The study II identified higher EMG activity of the middle and posterior deltoid in the TSP group compared to the control group and an increase of EMG activity of pectoralis major (sternal part) in the RSP group compared to the TSP and the control group. For the other muscles (anterior deltoid, teres major, pectoralis major - clavicular part and serratus anterior) significant differences were not found among groups. For all muscles, except the serratus anterior, EMG activity was lower during exercises without external load compared to exercises with 1 kg and elastic resistance. No main effect of group and load was found in the percentage of cocontraction. In study III, the control group showed higher maximum glenohumeral contact force when compared to TSP group during anteflexion, but no differences were found between groups of patients during both movements. Elastic resistance exercises showed higher glenohumeral contact force in all groups. The maximum force of all analyzed muscles ranged from 0,32 N to 772 N and the rotator cuff and deltoid muscles presented the highest values in all groups. This thesis suggests that for a same range of motion, patients with shoulder prosthesis present greater scapular motion compensating the loss of glenohumeral motion. Scapular kinematics and EMG activity of these patients were affected by the implementation of external loads, but not by the type of load, unlike the contact forces and muscle forces, in which the elastic resistance had greater influence. Moreover, the percentage of cocontraction was not influenced by the type of prosthesis and patient groups had lower glenohumeral contact forces compared to the control group.

APA, Harvard, Vancouver, ISO, and other styles

41

Szucs, Kimberly A. "Capturing Three-Dimensional Clavicle Kinematics During Arm Elevation: Describing the Contribution of Clavicle Motion and Associated Scapulothoracic Muscle Activation to Total Shoulder Complex Motion." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275406915.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Secchi, Leonardo Luiz Barretti. "Dinamometria isocinética dos músculos rotadores internos e adutores do ombro em nadadores. Estudo comparativo entre nados de braçadas alternadas e simultâneas." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-22092011-123945/.

Full text

Abstract:

OBJETIVO: Comparar a força muscular dos rotadores internos e adutores do ombro (propulsores da natação) dos estilos com braçada simultânea (borboleta e peito) e estilos com braçada alternada (livre e costas). CASUÍSTICA E MÉTODOS: Foram avaliados 46 ombros de nadadores federados dos estilo livre e costas (nado alternado GNA) com idade de 21,8 ± 3,8 anos; peso de 71,2 ± 10,0 kg, altura de 177,6 ± 8,5 cm e IMC= 22,3 ± 1,3; 44 ombros de nadadores federados dos estilos peito e borboleta (nado simultâneo - GNS) com idade de 20,3 ± 4,5 anos; peso de 70,5 ± 9,3 kg, altura 167,2 ± 37,6 cm e IMC= 22,6 ± 1,9; 28 ombros de nadadores recreacionais (grupo recreacional GR) com idade de 24,5 ± 4,5 anos; peso de 70,8 ± 16 kg, altura de 173,4 ± 9,2 cm e IMC= 23,3 ± 3,9 e 42 ombros de indivíduos controle (Grupo - GC) com idade de 25,8 ± 3,5 anos; peso de 68,7 ± 11,2 kg, altura 171,9 ± 9,3 cm e IMC= 23,2 ± 2,6. Todos foram avaliados no dinamômetro isocinético Biodex Multi-joint System 3® (Shirley, NY, USA) nas velocidades de 60º/segundo e 300º/segundo. Foram avaliados os movimentos de adução e rotação interna. As variáveis estudadas foram pico de torque corrigido pelo peso corpóreo (PTPC), trabalho total (TT) e relação agonista/antagonista. RESULTADOS: Não houve diferença na musculatura adutora entre os grupos GNS e GNA nas variáveis PTPC (GNS = 114,4 Nm e GNA = 109,4 Nm) e TT (GNS = 642,9J e GNA = 641,5J). Não houve diferença na relação abdução/adução do ombro entre GNS (67,4%) e GNA (68,3%). Não houve diferença na musculatura rotadora interna entre os grupos GNS e GNA nas variáveis PTPC (GNS = 66,4Nm e GNA = 63,4Nm) e TT (GNS = 517,4J e GNA 526,7J). Não houve diferença na relação rotação externa e rotação interna o ombro entre GNS (65,7%) e GNA (61,5%). CONCLUSÃO: Não há diferença na força muscular dos músculos adutores e rotadores internos do ombro quando se compara nados com braçadas simultâneas e alternadas
OBJECTIVE: To compare the muscle strength of internal rotators and adductors of the shoulder (of the propellants swimming) of styles with simultaneous stroke (butterfly and breaststroke) and stroke with alternating colors (free and back). PATIENTS AND METHODS: We evaluated 46 shoulders of competitive swimmers of freestyle and back (alternating swimming - GNA) aged 21.8 ± 3.8 years, weight 71.2 ± 10.0 kg, height 177.6 ± 8.5 cm and BMI = 22.3 ± 1.3. 44 shoulders of competitive swimmers of styles breast and butterfly (swimming simultaneously - GNS) aged 20.3 ± 4.5 years, weight 70.5 ± 9.3 kg, height 167.2 ± 37.6 cm and BMI = 22.6 ± 1.9. Shoulders of 28 recreational swimmers (group recreational - GR) aged 24.5 ± 4.5 years, weight 70.8 ± 16 kg, height 173.4 ± 9.2 cm and BMI = 23.3 ± 3, 9:42 shoulders of individuals (control group - CG) aged 25.8 ± 3.5 years, weight 68.7 ± 11.2 kg, height 171.9 ± 9.3 cm and BMI = 23, 2 ± 2.6. All were assessed using an isokinetic dynamometer Biodex Multi-joint System 3 ® (Shirley, NY, USA) at 60 ° / second and 300 º / second. We evaluated the movements of adduction and internal rotation. The variables were peak torque corrected for body weight (PTPC), total work (TW) and agonist / antagonist. RESULTS: There was no difference in the adductor muscle between the groups in the variables and GNA GNS PTPC (Nm) (GNS = 114.4 and 109.4 = GNA) and TT (J) (GNS = 642.9 and 641.5 = GNA). There was no difference in the abduction / adduction (%) of the shoulder between GNS (GNS = GNA = 67.4 and 68.3). There was no difference in the internal rotator muscles between the groups in the variables and GNA GNS PTPC (Nm) (GNS and GNA = 66.4 = 63.4) and TT (J) (GNS = 517.4 and 526.7 GNA). There was no difference in the external rotation and internal rotation (%) of the shoulder between GNS (GNS = GNA = 65.7 and 61.5). CONCLUSION: No difference in muscle strength of adductor muscles and internal rotators of the shoulder when comparing births with simultaneous and alternate strokes

APA, Harvard, Vancouver, ISO, and other styles

43

Doede, Aubrey L. "Electromyographic Analysis of Trunk Muscle Activation During a Throwing Pattern Following Rotator Cuff Mobilization." Scholarship @ Claremont, 2010. http://scholarship.claremont.edu/cmc_theses/90.

Full text

Abstract:

Correct muscular activation of the body segments during an overhand throw is achieved when movement originates in the larger and more proximal legs and trunk and moves sequentially to the smaller, distal segments of the shoulder and arm. This sequence permits angular velocity to transfer progressively through the throw as part of an open kinetic chain. The athlete can summate angular velocity and segmental forces only if he is able to create a separation between the body segments during the movement pattern, and this separation is thus essential to effective segmental sequencing for activation of the trunk muscles to occur separately from distal segment motion. Limited mobility of the shoulder and scapula during the kinematic sequence will limit the ability of that segment to receive and contribute to the angular velocity of its proximal neighbors and to apply its own muscle torque to the throwing implement. This may result in compensatory motion of the proximal muscle groups to meet the demands placed on the body. To establish a link between compensatory activation of the trunk muscles and mobility in the rotator cuff and to apply this relationship to the pattern of the overhand throw, activity in the latissimus dorsi and external oblique/quadratus lumborum muscles was measured using surface electromyography in 40 college-age participants during arm flexion and lateral shoulder rotation. Muscle activation was recorded both before and after mobilization of relevant throwing muscles through targeted functional exercise. Results showed no significant change but suggested a general decrease in the level of peak muscle activation after participants engaged shoulder exercises. This is indicative of a downward trend in compensatory trunk activation during the initiation of shoulder motion. An increase in overall trunk muscle activity was also observed after exercise, which may imply a simultaneous engagement of the proximal throwing muscles in response to shoulder motion.

APA, Harvard, Vancouver, ISO, and other styles

44

Sun, Chunyi. "Ergonomic and Time Cost of One-Handed Lifting tasks as a Function of Shelf Height, Item Weight and Walking Distance." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1566123193772717.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Netto, Walter Ansanello. "Desempenho muscular durante a protração e retração da escápula em sujeitos com instabilidade glenoumeral traumática anterior." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/5336.

Full text

Abstract:

Made available in DSpace on 2016-06-02T20:19:25Z (GMT). No. of bitstreams: 1 6272.pdf: 943725 bytes, checksum: fe22255b4e68c17bf799b7fcb6c4e5d4 (MD5) Previous issue date: 2014-02-26
Financiadora de Estudos e Projetos
Traumatic anterior glenohumeral instability makes the humeral head unable to remain centered on the glenoid fossa and alters the arthrokinematics and the strength of the shoulder rotators. The rotator cuff muscles depend on a good performance of the scapular muscles and their strengthening has been recommended at different levels for subjects with traumatic anterior glenohumeral instability. On the other hand, poor scapular performance is not well described in this population. Therefore, the aim of this thesis was to investigate muscle performance during protraction and retraction of the scapula in the sagittal and scapular planes in subjects with traumatic anterior glenohumeral instability. The study included 40 volunteers of both sexes, divided into two groups: control group (n = 20) and patients with traumatic anterior glenohumeral instability (n = 20). Muscle performance during protraction and retraction was assessed using Biodex System III isokinetic dynamometer in the isometric mode, with three repetitions, and in the concentric isokinetic mode, at the speeds of 12.2 cm/s and 36.6 cm/s, with 5 and 10 repetitions, respectively. The evaluations were performed with the shoulder flexed at 90° in the sagittal plane and elevated at 90° in the scapular plane. The mean peak force, total work and the total range of motion (ROM) were the variables of interest. The variables were compared using analysis of variance with two factors (ANOVA - Two Way), considering plans as the withinsubject factor and group as the between-subject factor, at a significance level of 5%. There was difference between subjects in the average peak force at isometric protraction and retraction and also at protraction during isokinetic evaluation at 36 cm/s (p <0.05). For intra-subject analysis (scapular plane vs sagittal plane), differences were found for mean peak force during isometric protraction, isokinetic protraction at 12.2 cm/s and isokinetic protraction at 36.6 cm/s. There was an interaction for the total work in retraction at 12.2 cm / s, total work in retraction at 36.6 cm / s for ROM. This dissertation shows that subjects with traumatic anterior glenohumeral instability have decreased strength in protraction and in isometric retraction and also in isokinetic contraction. Average peak force, total work and ROM in the sagittal plane are higher than in the scapular plane.
A instabilidade glenoumeral traumática anterior torna a cabeça umeral incapaz de manter-se centralizada na fossa glenoidal. Essa disfunção altera a artrocinemática e a força dos rotadores do ombro. Os músculos do manguito rotador dependem de um bom desempenho dos músculos escapulares e, assim, seu fortalecimento tem sido recomendado em planos diferentes, em sujeitos com instabilidade glenoumeral traumática anterior. Por outro lado, o comprometimento do desempenho escapular não está claro nessa população. Diante disso, o objetivo desta dissertação foi investigar o desempenho muscular de protração e retração da escápula no plano sagital e escapular em sujeitos com instabilidade glenoumeral traumática anterior. Participaram deste estudo 40 voluntários de ambos os sexos, divididos em dois grupos: grupo controle (n=20) e grupo com instabilidade glenoumeral traumática anterior (n=20). O desempenho muscular de protração e retração foi avaliado por meio do dinamômetro isocinético Biodex System III, no modo isométrico, com 3 repetições, e no modo isocinético concêntrico, nas velocidades 12,2 cm/s e 36,6 cm/s, com 5 e 10 repetições, respectivamente. As avaliações foram realizadas com o ombro posicionado a 90° de flexão no plano sagital e a 90º de elevação no plano da escápula. A média dos picos de força, o trabalho total e a amplitude total de movimento (ADM) foram as variáveis de interesse. As variáveis foram comparadas, utilizando-se a análise de variância com dois fatores (ANOVA Two Way), com os planos como fator intrassujeitos e grupo como fator entressujeitos, a um nível de significância de 5%. Houve diferença entressujeitos para a média dos picos de força em protração e retração isométrica e também em protração durante a avaliação isocinética a 36 cm/s (p<0.05). Para a análise intrassujeitos (Plano escapular vs Plano sagital), as diferenças foram encontradas para a média dos picos de força durante a protração isométrica, protração isocinética a 12,2 cm/s e protração isocinética a 36,6 cm/s. Houve interação para o trabalho total em retração a 12,2 cm/s, trabalho total em retração a 36,6 cm/s e para a ADM. Esta dissertação permite concluir que sujeitos com instabilidade glenoumeral traumática anterior apresentam diminuição de força em protração e retração isométrica e em retração isocinética. A média dos picos de força, o trabalho total e a ADM no plano sagital são maiores do que no plano escapular.

APA, Harvard, Vancouver, ISO, and other styles

46

Dias, Rodrigo Vasconcelos. "Toxina botulínica tipo A como tratamento da síndrome do ombro doloroso hemiplégico." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/17/17142/tde-05122016-114044/.

Full text

Abstract:

O Acidente Vascular Cerebral (AVC) é um quadro de alta incidência e uma das principais causas de incapacidade no mundo. Uma de suas complicações frequentes e de grande impacto na funcionalidade é a Síndrome do Ombro Doloroso Hemiplégico (SODH). O presente trabalho consiste em revisar a literatura a respeito da eficácia do tratamento da SODH com toxina botulínica tipo A (TXB-A). Foram pesquisados os bancos de dados eletrônicos PubMed e ISI web of Science, no período de 1996 a 2014. Incluímos os estudos tipo ensaio clínico duplo-cego, randomizado e aleatorizado que utilizaram a TXB-A como tratamento da SODH. Os artigos deveriam obter pontuação 3 ou superior pelos critérios de Jadad. Seis estudos foram encontrados e dois foram considerados de baixa qualidade. Os quatro artigos restantes possuíam 114 participantes no total. Três autores avaliaram os artigos de forma independente quanto aos critérios de inclusão. A extração de dados incluiu as características dos pacientes, dose e marca comercial da TXB-A utilizada, músculos e efeitos na avaliação da dor. Houve grande variação de dose, técnicas de aplicação e músculos tratados, bem como das intervenções após a aplicação. Três estudos demonstraram efeitos positivos do tratamento da dor e função do membro superior. A meta-análise não pode ser realizada, pois a informação quantitativa necessária foi indisponível. Os resultados da literatura são discordantes e apesar dos indícios serem favoráveis, não há resultados estatisticamente significantes para corroborar tal prática. Maior investigação e pesquisa são necessários para definir a indicação da TXB-A como tratamento da SODH. Mesmo assim, esta abordagem pode ser considerada particularmente quando a espasticidade é relevante. A intervenção pode ser realizada como uma alternativa ou ser utilizada em combinação com outros tratamentos. Para melhores resultados, mais de um músculo deve ser alvo, preferencialmente os músculos peitoral maior e subescapular.
The Stroke presents a high incidence and is a major cause of disability the in the world. One of it`s frequent complications and a cause of great loss of quality of life is the post-stroke shoulder pain (PSSP). The purpose of this study is to explore the effectiveness of botulinum neurotoxin type A (BoNT-A) in the treatment of PSSP. The electronic databases PubMed and ISI web of Science were searched from 1996 to 2014. We included double-blind randomized controlled trials that used BoNT-A for the treatment of PSSP in spastic hemiplegic patients. Articles should be scored 3 or more with the Jadad criteria. Six studies fulfilled the first search and two were considered low quality. The four remaining studies comprised 114 participants. Three authors independently evaluated articles eligible for inclusions. Data extracted included patient characteristics, doses and types of commercialized BoNT-A used, muscles injected, and effects on pain evaluation. There was a large variation in doses, injection techniques and treated muscles, as well as post-injection interventions. Three studies demonstrated positive effects of BoNT-A in the treatment of pain or upper limb functioning. Meta-analysis was not performed because of unavailable quantitative data. Literature results are discordant and despite evidence be favorable, there are no statistically significant results to support this practice. Further investigation and research is needed to define the indication of BoNT-A on PSSP. Nevertheless, this approach can be seen particularly when the spasticity is relevant. The intervention may be performed as an alternative or used in combination with other treatments. For best results, more than one muscle should be targeted, preferably the pectoralis major and subscapularis muscles.

APA, Harvard, Vancouver, ISO, and other styles

47

Cajueiro, Monique Oliveira Baptista. "Ajustes posturais dos músculos escapulares e globais como mecanismos de controle do movimento do ombro e da postura." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/100/100139/tde-05022019-224602/.

Full text

Abstract:

A falha na estabilidade escapular e no ritmo escápulo-umeral são associadas ao risco de lesão no complexo do ombro. Apesar de se saber que a estabilização ativa dos músculos escapulares é fundamental para evitar disfunções ainda pouco se sabe sobre como o controle postural no complexo do ombro ocorre e como tais mecanismos poderiam auxiliar na estabilização da articulação perante uma tarefa. Será que há ajustes posturais antecipatórios (APA) e compensatórios (APC) nos músculos escapulares (serrátil anterior, trapézio inferior e trapézio superior) em tarefas motoras que envolvem o movimento dos membros superiores? Como as ações motoras modulam a resposta postural dos músculos escapulares e globais (músculos do tronco e membros inferiores) para estabilizar e orientar o corpo? O objetivo deste estudo foi analisar a existência dos ajustes posturais antecipatórios e compensatórios nos músculos escapulares e globais em sujeitos ativos saudáveis em tarefas de membros superiores. Para tal, participaram 70 indivíduos ativos saudáveis (18 mulheres e 52 homens, 28,0±7,2 anos, 70,5±13,4 kg e 1,72±0,07 m). Foi mensurada atividade eletromiográfica do músculo focal Deltóide Anterior, músculos escapulares (Serrátil Anterior, Trapézio Superior, Trapézio Inferior) e músculos globais (Reto Abdominal, Eretor Longuíssimo, Reto Femoral, Bíceps Femoral, Gastrocnêmio, Tibial Anterior) em 4 tarefas de membros superiores (abdução no plano escapular, adução, flexão e extensão) executadas com halteres de massa 1kg e 3kg. Os resultados mostraram a existência de ajustes posturais dos músculos escapulares (p<0,001); a tarefa e massa influenciaram nos ajustes posturais antecipatórios e compensatórios (p<0,001); as tarefas de adução versus extensão não apresentaram diferença entre si na atividade muscular dos músculos escapulares durante os ajustes posturais antecipatórios e compensatórios (p>0,05); as tarefas de abdução versus flexão são semelhantes com massa 1kg (p>0,05), mas se tornam diferentes com massa 3kg (p<0,001) com relação a atividade muscular dos músculos escapulares e globais; nas tarefas de flexão e abdução os maiores ajustes posturais foram dos músculos escapulares (Serrátil Anterior e Trapézio Inferior) (p<0,001); nas tarefas de adução e extensão os maiores são dos músculos globais (p<0,001); os ajustes posturais antecipatórios e compensatórios foram maiores nos músculos escapulares Serrátil Anterior e Trapézio Inferior do que no músculo focal Deltóide Anterior (p<0,001); existiu modulações nos tipos e níveis de APA e APC nas tarefas de membros superiores (p<0,001). Em conclusão, temos uma associação de ajustes posturais como mecanismos de estabilização e orientação do ombro em tarefas dos membros superiores. No entanto, a intensidade e modulação dos ajustes posturais são afetadas pela tarefa e massa. Acreditamos que a atividade muscular dos músculos escapulares esteja diretamente associada a necessidade de minimizar a perturbação para a manutenção da orientação e estabilidade segmento (ombro), assim como atividade dos músculos globais está associada a manutenção da estabilidade e orientação do corpo. Esses achados podem ser utilizados para futuros estudos comparando sujeitos com disfunção e saudáveis e assim entender se há atividade anormal dos músculos escapulares nos períodos de ajustes posturais antecipatórios e compensatórios e se esta atividade muscular contribui para disfunção do complexo do ombro
The failure of scapular stability and scapulohumeral rhythm is associated with the risk of injury to the shoulder complex. Although it is known that the active stabilization of the scapular muscles is fundamental to avoid dysfunctions, little is known about how postural control in the shoulder complex occurs and how such mechanisms could help stabilize the joint before a task. Are there anticipatory postural adjustments (APA) and compensatory (CPA) in the scapular muscles (serratus anterior, lower trapezius and upper trapezius) in motor tasks involving the movement of the upper limbs? How do motor actions modulate the postural response of the scapular and global muscles (trunk muscles and lower limbs) to stabilize and guide the body? The objective of this study was to analyze the existence of anticipatory and compensatory postural adjustments in the scapular and global muscles in healthy subjects in upper limb tasks. To do this, participated 70 healthy active individuals (18 women and 52 men, 28,0±7,2 years 70,5±13,4 kg and 1,72±0,07 m). It Was measured electromyographic activity of focal muscle (Deltoid Anterior), scapular muscles (Serratus Anterior, Upper Trapezius, Lower Trapezius) and global muscles (Rectus Abdominis, Longissimus, Rectus Femoris, Biceps Femoris, Gastrocnemius, Tibial Anterior) was measured in 4 upper limb tasks (abduction in the scapular plane, adduction, flexion and extension) performed with dumbbells of 1kg and 3kg mass. The results showed the existence of postural adjustments of the scapular muscles (p <0.001); the task and mass influenced the anticipatory and compensatory postural adjustments (p <0.001); the tasks of adduction versus extension did not difference among themselves in the muscular activity of the scapular muscles during the anticipatory and compensatory postural adjustments (p> 0.05); the abduction versus flexion tasks are similar with mass 1kg (p> 0.05), but become different with mass 3kg (p <0.001) in relation to muscular activity of the scapular and global muscles; during flexion and abduction tasks, the greatest postural adjustments were the scapular muscles (Serratus Anterior and Lower Trapezius) (p <0.001); during adduction and extension tasks, the largest of the global muscles (p <0.001); anticipatory and compensatory postural adjustments were higher in the serratus anterior and lower trapezius scapula muscles than in the anterior deltoid focal muscle (p <0.001); there were modulations in the types and levels of APA and CPA in upper limb tasks (p <0.001). In conclusion, we have an association of postural adjustments as mechanisms of stabilization and orientation of the shoulder in tasks of the upper limbs. However, the intensity and modulation of postural adjustments are affected by task and mass. We believe that the muscular activity of the scapular muscles is directly associated with the need to minimize the perturbation to the maintenance of the orietantion and stability segment (shoulder), as well as overall muscle activity is associated with maintaining stability and body orientation. These findings can be used for future studies comparing subjects with dysfunction and health and thus to understand if there is abnormal activity of the scapular muscles in the periods of anticipatory and compensatory postural adjustments and if this muscular activity contributes to dysfunction of the shoulder complex

APA, Harvard, Vancouver, ISO, and other styles

48

Freitas, Poliane Silva. "Análise isocinética dos músculos rotadores do ombro em atletas de basquetebol adaptado e indivíduos sedentários com lesão medular." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/17/17142/tde-10012017-115330/.

Full text

Abstract:

A articulação do ombro é muito solicitada em indivíduos com lesão medular usuários de cadeira de rodas, seja no deslocamento diário, na propulsão da cadeira de rodas ou na prática paradesportiva. Diante dessa realidade, este estudo teve por objetivo avaliar e comparar o desempenho muscular através do pico de torque corrigido pela a massa corporal, o trabalho e a potência dos grupos musculares do manguito rotador, relacionados aos movimentos de rotação interna e externa dos ombros, em atletas de basquetebol em cadeira de rodas, com trauma raquimedular, comparando-os com indivíduos com trauma raquimedular, sedentários, utilizando como instrumento o dinamômetro isocinético da marca 4 BIODEX®. Foram avaliados 36 indivíduos com trauma raquimedular, com níveis de lesão completa abaixo de T1 e idades entre 18 e 45 anos. Sendo 18 indivíduos atletas de basquetebol em cadeira de rodas e 18 indivíduos cadeirantes sedentários. Os testes isocinéticos foram realizados na posição sentada, com o ombro em 45° de abdução no plano da escápula e 30° de flexão no plano frontal, com amplitude de movimento de 70°, sendo 40° em rotação externa e 30° para rotação interna. O protocolo foi realizado por meio do teste isocinético com cinco repetições para as velocidades de 60°/s e 180°/s, com propósito de avaliar o pico de torque/peso e o trabalho, e 10 repetições em 300°/s para avaliar a potência muscular, em ambos os ombros, com intervalo de 1 minuto, entre as repetições. As comparações entre as variáveis foram analisadas com o teste do quiquadrado ou teste exato de Fisher. Para a análise das diferenças entre as médias das variáveis contínuas, utilizou-se o teste t, com nível de significância de 5%. Como resultado, observou-se semelhança das variáveis antropométrica entre os grupos; o pico de torque/peso, o trabalho e a potência muscular dos rotadores internos e externos de ambos os ombros dos atletas de basquetebol em cadeira de rodas foram significativamente maiores quando comparados com o grupo controle, em todas as velocidades testadas (P <0,001); também foi encontrada uma correlação do ganho de força muscular com o tempo de lesão medular. Conclui-se que os atletas cadeirantes apresentaram maior desempenho muscular em relação aos cadeirantes que não praticavam nenhum tipo de esporte.
The shoulder joint is much, requested in individuals with spinal cord injury wheelchair users, at offset journal, in wheelchair propulsion, as well as in practice to-sports. Facing this reality, the present research aimed to evaluate and compare the performance through muscle peak torque fixed by body mass, the work and the power of the rotator cuff muscle groups, related to the movements of internal and external rotation of the shoulder, in basketball, wheelchair athletes with spinal cord injury, comparing them to individuals with spinal cord injury, sedentary using as an instrument the isokinetic dynamometer 4 BIODEX® brand. 36 individuals were evaluated with spinal cord injury, with complete injury levels below T1 and between the ages of 18 to 45 years. Being 18 individuals athletes of wheelchair basketball and wheelchair accessible, sedentary individuals 18. The isokinetic tests were performed in a sitting position, with the shoulder in 45° of abduction in scapula and 30° of flexion in the frontal plane, with range of motion of 70°, and 40° in external rotation and 30° for internal rotation. The Protocol was carried out through the isokinetic test with 5 reps for 60°/s speeds and 180°/s with purpose to assess the peak torque/weight and work, and 10 repetitions at 300°/s to assess muscle power, in both shoulders, with 1 minute interval between repetitions. The comparisons between the variables were assessed the Chi-square test or Fisher\'s exact test. For the analysis of the differences between the media of the variables keep, used the t test, with a significance level of 5%. As a result, it was observed there similarity between the groups Anthropometric, that the peak torque/weight work and muscle power of internal and external rotators of both shoulders of the athletes of wheelchair basketball was significantly higher when compared with the control group, the tested velocities (P < 0.001) and correlation of muscle strength gain with time of spinal cord injury. It is concluded that the wheelchair athletes has increased muscle performance in relation to wheelchair users who do not practice any kind of sport.

APA, Harvard, Vancouver, ISO, and other styles

49

Romaneiro, Carla Patricia Fadista. "Efeitos do treino compensatório específico na força dos rotadores internos e externos dos ombros em jovens nadadoras de natação sincronizada." Master's thesis, Universidade de Évora, 2012. http://hdl.handle.net/10174/14916.

Full text

Abstract:

O objetivo deste estudo é avaliar a existência de desequilíbrios musculares entre os rotadores dos ombros de nadadoras de sincronizada e verificar se o trabalho de força compensatório específico poderá minimizar as diferenças. A amostra foi constituída por 18 nadadoras divididas em dois grupos: grupo experimental, (N = 10) que realiza treino normal de água e trabalho compensatório, e o grupo de controlo (N = 8) que realizavam apenas o treino de água. Foram aplicados protocolos para avaliar as seguintes variáveis: a força máxima (3 repetições a 60º/s), e a força resistente (20 repetições a 180º/s) nos ombros, com a utilização de um dinamómetro isocinético (Biodex System 3). Concluímos que não existem desequilíbrios musculares ao nível dos rotadores do ombro, nem diferenças nos rácios entre os 2 membros. O programa de treino compensatório não promoveu alterações significativas nas variáveis estudadas. O destreino parece ter efeitos ao nível dos RE no MD; ABSTRACT: The purpose of this study is to evaluate the existence of muscular imbalances between the shoulder’s rotators of synchronized swimmers and if the specific compensatory work force minimizes the afore mentioned differences. The research sample consisted of 18 swimmers divided into two distinct groups: the training group (N = 10), performing normal water training and compensatory work force and the control group (N = 8), performing only the water training. In this study were applied protocols to evaluate the following variables: the maximum strength (three 60º/s repetitions) and the resistance strength (twenty repetitions of 180º/s) on the shoulders, using an isokinetic dynamometer (Biodex System 3), We concluded that there are no muscular imbalances at the shoulder’s rotators level nor diferences in the ratios between both shoulders. The strength compensatory training did not promoted significant changes in the studied variables. Untraining seems to have effects at ER level of the DS.

APA, Harvard, Vancouver, ISO, and other styles

50

Alexander, Caroline Martha. "Reflex control of shoulder girdle muscles in humans." Thesis, University College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396152.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'Shoulder muscle'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles