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1
Nilpawar, A. M. "Kinematics and collision kinetics in high shear granulation." Thesis, University of Sheffield, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.506744.
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Shin, Dong-Min. "The jump landing impact absorption kinematics and kinetics." Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/834520.
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The purpose of this study was to determine the jump landing impact absorption kinematic and kinetic characteristics of the four subject groups: a) male high school athletes, b) female high school seasonal athletes, c) female high school year-round athletes, and d) female college athletes who train year-round. Subjects dropped onto a force platform from a height of 40 centimeters. Variables analyzed were flexibility, strength, Fz, Fy, and Fx force, free moment, range of motion, contact and maximum angles, time to maximum angle, contact and maximum angular velocities, and time to maximum angular velocity. Significant differences among subject groups were determined through use of a factorial analysis of variance and Scheffe' post hoc test.A difference was noted in the landing patterns of males and females. Male subjects exhibited a significantly longer time to first vertical peak force. This longer time may allow for greater initial force attenuation; however, the male athletes had a significantfy greater second peak force. Males also differed significantly from females in anteroposterior and mediolateral force.The differences in method of force attenuation may be due to significantly greater ankle eversion shown by the males and greater knee flexion used by the females. Additionally, the males had significantly greater leg strength, which may have allowed them to increase the time to first peak.The year round female high school athletes were found to use the best biomechanical landing method. They had a greater range of motion in the knee and ankle, and subsequently produced the lowest amount of vertical and anterio-posterior force.School of Physical Education
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Acevedo, Navine N. "Effects of shoe geometry on kinematics and kinetics of gait." To read this dissertation, search for it in Kinesiology Publications database, 2004. http://www.oregonpdf.org.
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Torabi, Abbas. "An investigation of the kinetics and excited state dynamics of the nitrate free radical." Diss., Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/28024.
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Mizell, Ryan Ashley. "Anticipatory effects on lower extremity kinematics and kinetics during cutting movements." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0025113.
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McCarren, Gillian A. "The Impact of Dual Task Shooting on Knee Kinematics and Kinetics." Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1556214323893082.
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Oakley, Paul Alexander. "Changes in three-dimensional knee kinematics and kinetics within normative gait speeds." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq52931.pdf.
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Renaud, Susie. "Kinetics and Kinematics of the Overhand, Hybrid and Sidearm Shot of Lacrosse." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/30319.
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Lacrosse, Canada’s national summer sport, is a sport anchored in first nations’ tradition. Its growing popularity in North America has not been reflected by a similar interest in the scientific literature more specifically on the biomechanics of the lumbar spine with its throwing motion. The aim of this study was to describe the motions, forces and muscle actions of the lumbar spine with the hybrid, overhand and sidearm throw. Twelve subjects were asked to throw at maximal speed while captured by a 3D motion analysis system. Flexion, extension and axial rotation angular velocities as well as positive and negative powers in the two planes were calculated. The first research question pertained to consistency in angular velocities and powers between trials of a given throwing technique. Subjects showed a fairly high variation on all variables but mostly with the angular velocities in extension and the peak positive power in flexion/extension which had high coefficient of variations (CVs). The contralateral rotation velocity and the positive rotation power had the lowest CVs. Overall the CVs for powers exceeded the angular velocities’. The second research question addressed if a difference in variables was present between the three throwing methods. A significant difference was observed in the peak negative power in flexion/extension and the peak positive power in rotation. The contralateral rotation angular velocity also showed a significant difference but the sphericity assumption failed. No other variable showed a significant difference but the observed power for those variables was also quite small. Due to the lack of power and the further need for controlling some unforeseen sources of error, this study can be used as a pilot study to further define and improve future studies in the field of lacrosse biomechanics.
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Bolt, Lori Rebecca. "The effect of running poles on the kinetics and kinematics of jogging." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1177970.
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Chronic knee injury accounts for nearly half of the injuries from which runners suffer. Impact and propulsive forces are believed to contribute to the development of overuse injuries, so one method of protecting runners might be to reduce those forces. The purpose of this study was to examine the biomechanical role of running poles by comparing normal running to pole running. Ground reaction forces, tibial acceleration, and video data were collected on ten middle-age male recreational runners with a history of knee pain. Subjects ran across a force plate at a constant velocity of 3.5-3.7m/s with an accelerometer attached to the anteromedial aspect of the tibia. Hip, knee, and ankle joint range of motion and torque were calculated. Results indicated significant decreases in the average peak propulsive force and impulse, and a significant increase in peak hip joint torque. It was concluded that by providing an outside source of propulsion, running poles may be useful in reducing the risk of injury to runners.School of Physical Education
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Yontz, Nicholas Allen. "Determining the Correlation Between Core Performance and Golf Swing Kinematics and Kinetics." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281540237.
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Fortenbaugh, David. "The Biomechanics of the Baseball Swing." Scholarly Repository, 2011. http://scholarlyrepository.miami.edu/oa_dissertations/540.
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Success in baseball batting is fundamental to the sport, however it remains one of, if not the most, challenging skills in sports to master. Batters utilize the kinetic chain to transfer energy from the lower body to the upper body to the bat, hoping to impart the maximum amount of energy into the ball. Scientists and coaches have researched the swing and developed theories on the keys for successful batting, but most of this research has been inadequate in attempting to fully describe the biomechanics of batting. The purposes of this study were to improve upon the methodology of previous researchers, provide a full biomechanical description of the swing, and compare swings against pitches thrown to different locations and at different speeds. AA-level Minor League Baseball players (n=43) took extended rounds of batting practice in an indoor laboratory against a pitcher throwing a mixture of fastballs and changeups. An eight camera motion analysis system and two force plates recording at 300 Hz captured the biomechanical data. The swing was divided into six phases (stance, stride, coiling, swing initiation, swing acceleration, and follow-through) by five key events (lead foot off, lead foot down, weight shift commitment, maximum front foot vertical ground reaction force, and bat-ball contact). Twenty-eight kinematic measurements and six ground reaction force measurements were computed based on the marker and force plate data, and all were assessed throughout the phases. First, a comprehensive description of a composite of the batters’ swings against fastballs “down the middle” was provided. Second, successful swings against fastballs thrown to one of five pitch locations (HIGH IN, HIGH OUT, LOW IN, LOW OUT, MIDDLE) were compared in terms of selected kinematics at the instant of bat-ball contact, timing and magnitude of peak kinematic velocities, and timing and magnitude of peak ground reaction forces. Third, these variables were once again compared for swings against fastballs and changeups. A large number of biomechanical differences were seen among the swings against various pitch locations. More fully rotated positions, particularly of the pelvis and bat were critical to the batters’ successes on inside pitches while less rotated positions keyed successes against outside pitches. The trail and lead arms worked together as part of a closed chain to drive the hand path. Successful swings had the trail elbow extended more for HIGH IN and flexed more for LOW OUT, though batters often struggled to execute this movement properly. A distinct pattern among successful swings against fastballs, successful swings against changeups, and unsuccessful swings against changeups was witnessed; namely a progressive delay in which the batter prematurely initiated the events of the kinetic chain, especially when unsuccessful in hitting a changeup. It was believed that this study was much more effective in capturing the essence of baseball batting than previous scientific works. Some recommendations to batting coaches would be to get batters to take a consistent approach in the early phases of every swing (particularly for the lower body), identify both pitch type and location as early as possible, use the rotation of the pelvis to propagate the energy transfer of the kinetic chain from the group to the upper body, and use the pelvis, and subsequently, the upper body, to orient the trunk and hands to an optimal position to drive the ball to the desired field. Limitations of the current study and ideas for future work were also presented to better interpret the findings of this research and further connect science and sport.
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Brisson, Nicholas. "A Comparison of Preoperative and Postoperative Lower-extremity Joint Biomechanics of Patients with Cam Femoroacetabular Impingement." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20256.
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Surgery to correct cam femoroacetabular impingement (FAI) is increasingly popular. Despite this, no known study has used motion analysis and ground reaction forces to quantify the outcome of surgery for FAI. The goal of this study was to compare the preoperative and postoperative lower-extremity joint kinematic and kinetic measurements of cam FAI patients during activities of daily living with use of a high-speed motion capture system and force platforms. We hypothesized that the lower-extremity joint mechanics of FAI patients during level walking and maximal squatting would resemble more those of healthy control subjects, after surgery. Ten patients with unilateral symptomatic cam FAI, who underwent corrective surgery using an open or combined technique, performed walking and maximal depth squatting trials preoperatively and postoperatively. Thirteen healthy control subjects, matched for age, sex and body mass index, provided normative data. Results showed that postoperatively, FAI patients had reduced hip ROM in the frontal and sagittal planes, produced smaller peak hip abduction and external rotation moments, and generated less peak hip power compared to the control group during level walking. During maximal squatting, postoperative FAI patients squatted to a greater depth, and had larger knee flexion and ankle dorsiflexion angles, as well as the sum of all joint angles of the affected limb at maximal depth compared to the preoperative values. The lower-extremity joint and pelvic mechanics of FAI patients did not fully return to normal after surgery. Although surgery seemed to reduce hip pain and restore a normal femoral head-neck offset, it further impaired muscle function as a result of muscle incisions. More research is needed to determine the effects of muscle incisions, which could help improve surgical techniques and develop better rehabilitation programs for FAI patients.
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Denton, Jamie. "The kinematic, kinetic and blood lactate profiles of continuous and intra-set rest loading schemes a thesis submitted to the Auckland University of Technology in partial fulfilment of the degree of Master of Health Science, January 2005." Full thesis. Abstract, 2005. http://puka2.aut.ac.nz/ait/theses/DentonJ.pdf.
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Law, Nok-Hin. "Kinematics & Kinetics Analysis of the Lower Extremity of Normal Weight, Overweight, and Obese Individuals During Stair Ascent & Descent." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24033.
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The purpose of this study was to examine the effects of body mass and sex on the joint biomechanics of the lower extremity during stair ascent and descent. Nineteen normal weight (8M and11F; BMI: 22.1 ± 1.8 kg/m2), 18 overweight (14M and 4F; BMI: 27.4 ± 1.3 kg/m2) and 8 obese subjects (3M and 5F; BMI: 33.3 ± 2.5 kg/m2) were recruited. Joint mechanical loading presented by joint moment of force and peak joint angles at the hip, knee, and ankle during stair climbing were recorded and analyzed using a motion analysis system with 10 cameras and 4 force plates. The MANOVA and linear regression analysis found a significantly larger knee extensor moment (p=0.026) among the overweight compared to the normal weight participants during descent. Sex differences were found in the peak joint angles, as the females abducted their knees more than the males (p=0.002; r(51) = 0.51) during descent.
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Johnston, Christopher. "On the kinematics and kinetics of the distal limb in the standardbred trotter /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1997. http://epsilon.slu.se/avh/1997/91-576-5414-X.gif.
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Sinclair, Jonathan. "The kinetics, kinematics and energy requirements of distance running : implications for footwear design." Thesis, University of Central Lancashire, 2012. http://clok.uclan.ac.uk/8512/.
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As the primary interface between the runner and the road, athletic footwear has a potentially important role to play in the reduction/management of chronic injuries and enhancement of performance. Over the past thirty years the running shoe has changed considerably. However, despite significant advances in footwear technology, the incidence of injury in distance runners has not altered meaningfully. It has been postulated that poor footwear selection is the mechanism behind this, whereby running shoes are incorrectly selected/inappropriate for the populations and situations in which they are worn. The investigations and results obtained from this thesis aim to attenuate this, and provide runners and footwear manuafacturers with new knowledge regarding the application of footwear to different populations and conditions in order to improve both injury occurence and performance. In addition to a significant amount of developmental analyses, four principal examinations were conducted as part of this thesis. Study 1 aimed to determine the kinetic and 3-D kinematic differences between treadmill and overground running, in order to determine whether the treadmill replicates overground running and whether different footwear is necessary during treadmill running. It was observed specifically that treadmill running was associated with significant increases in eversion and tibial internal rotation whilst overground runners exhibited greater peak tibial accelerations. It was concluded that treadmill runners are likely to require footwear with additional medial stability properties, aimed at reducing rearfoot eversion whilst overground runners should consider footwear with more advanced midsole cushioning properties designed to reduce the magnitude of impact transients. Study 2 examined the gender differences in the kinetics and 3-D kinematics of running in order to determine whether females require running shoes specifically tailored to their running mechanics. Females were associated with significant increases in eversion and tibial internal rotation; reaffirming the notion that they are more susceptible to overuse injuries than males. It is reccommended that females select running footwear with design characteristics aimed towards the reduction of rearfoot eversion in order to reduce the incidence of injury. Study 3 investigated the kinetics and 3-D kinematics of running: barefoot, in conventional running shoes and in barefoot inspired footwear in order to determine the efficacy of barefoot running in comparison to shod and also the ability of barefoot inspired footwear to closely mimic the 3-D kinematics of barefoot running. Barefoot running was associated with significant increases in impact parameters. It was also observed that barefoot inspired footwear does not closely mimic the 3-D kinematics of barefoot running. This leads to the final conclusion that barefoot running may not serve to reduce the incidence of injury. Study 4 aimed to examine the influence of footwear with different shock attenuating properties on the energy requirments of distance running and to investigate the biomechanical parameters which have the stongest association with running economy using regression analyses. Whilst footwear with different shock attenuating properties did not influence running economy, it was observed that a significant proportion of the variance in running economy could be explained by kinematic and EMG parameters. The thesis has provided information not previously available regarding the injury prevention and performance aspects of running footwear. It is clear that footwear cannot be universally prescribed and that the population and circumstances in which different shoes are used are key when selecting and designing appropriate running footwear.
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Sides, D. L. "Kinematics and kinetics of maximal velocity sprinting and specificity of training in elite athletes." Thesis, University of Salford, 2015. http://usir.salford.ac.uk/34332/.
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Maximal velocity sprinting has been studied extensively from a biomechanical standpoint, however little is known of the biomechanics characteristics at sprint velocities that typify elite athletic performance, due to the difficulties in accessing such athletes and collecting data within a competitive environment. Research has investigated the optimal training to achieve such velocities, with a focus on the specificity of training principle. However the specificity of the common training methods of elite sprinters is yet to be investigated from a biomechanical perspective. Investigations of ten international level sprinters in a competition environment revealed the kinematic variables which characterise sprint velocities exceeding 10.0m/s. Elite sprinters minimised the touchdown distance and knee flexion during ground contact, and terminated stance prior to full extension of the hip and knee. An additional kinetic analysis on six elite male sprinters revealed a greater hip angle at touchdown and higher maximum and average hip velocities in swing were associated with lower peak braking forces. Reduced hip and knee extension at toe-off along with a greater degree of maximum hip flexion were associated with a higher vertical impulse. A movement specificity framework was developed to quantify the holistic specificity of training methods based on biomechanical movement principles. The Bulgarian split squat drop had a high specificity to maximal velocity sprinting with respect to the loading principles. Running drills were highly specific based on coordination principles, in particular the leg extension velocities in the late phases of stance. The kinematic and kinetic models can be used by coaches to evaluate individual athletes against true elite sprinting, whilst the movement specificity framework can be utilised to design and maximise the specificity of sprint training programmes.
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Harris, Nigel K. "Kinetics and kinematics of strength and power development a thesis submitted to AUT University in fulfilment of the degree of Doctor of Philosophy, 2008." Click here to access this resource online, 2008. http://hdl.handle.net/10292/395.
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Preston, Jennifer Jacqueline Yu Bing. "Mechanism and timing effects on the kinematics and kinetics of the running and cutting motion." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,527.
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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 Biomedical Engineering (School of Medicine)." Discipline: Biomedical Engineering; Department/School: Medicine.
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Gage, Matthew J. "The Effects of Abdominal Training on Postural Control, Lower Extremity Kinematics, Kinetics, and Muscle Activation." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd3125.pdf.
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Moore, Chandler Dominique. "Effects of External Ankle Taping on Lower Extremity Kinetics and Kinematics in Young Adult Males." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1493290328872479.
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McCabe, Carla. "Effects of 50m and 400m race paces on three-dimensional kinematics and linear kinetics of sprint and distance front crawl swimmers." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/3300.
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Many authors have proposed that sprint and distance front crawl swimmers differ in their stroke characteristics, however little three-dimensional quantitative data is provided to support these assumptions. It is currently unknown whether sprint and distance swimmers exhibit distinct stroke characteristics when swimming at the same pace. There were two main purposes of this study: 1) to determine whether there are distinct kinematic and kinetic differences between sprint and distance front crawl swimmers, and 2) to investigate whether stroke characteristics of front crawl swimmers, in terms of kinematic and kinetic variables change with swimming speed. Fifteen male national/international front crawl swimmers (17.87 +/- 2.33yrs; 73.87 +/- 8.72kg; 183.02 +/- 6.84cm) volunteered to participate in this study. This sample was composed of seven sprint (SG) and eight distance (DG) swimmers. Each testing session required swimmers to perform four 25m sprints and one 400m max effort (front crawl), with no pacing strategy, in a randomised order. Each trial was performed through a 6.75m3 calibrated space and recorded by six gen-locked JVC KY32 CCD cameras (4 below and 2 above water) sampling at a frequency of 50 fields per second. All trials were processed using ‘APAS’ software to obtain 3D coordinate data. Anthropometric measures were quantified using the elliptical zone method. Both data sets were entered into a bespoke MATLAB program which output: average swim velocity (Vav), stroke length (SL), stroke frequency (SF), stroke index (SI), vertical and lateral displacement for each segment, shoulder and hip roll angle, and elbow joint angle variables (1st back, shoulder x, end back, hand exit and recovery elbow angle). Stroke phase (entry, pull, push and recovery) durations (%) were quantified at instants corresponding to percentiles of the stroke cycle. Centre of mass position data were obtained from the digitised 3D data using a 14 segment rigid link body model in conjunction with the body segment parameter data obtained by the elliptical zone method. Component whole body velocity (VCOMHor), acceleration (accCOM) and net force (forceCOM) were derived from the centre of mass position data. Variables were statistically analysed in SPSS v.14.0, using a General Linear Model, repeated measures analysis of variance. The results indicated that the groups differed (p<0.05) with respect to the duration of the pull phase, the occurrence of max left and right shoulder roll and the temporal sequencing of the shoulders and hips rolling at both sprint and distance pace. Other variables approached significance between the groups, particularly when distance swimming, such as the duration of the push phase (p=0.082), the Vav (p=0.071) and average VCOMHor (p=0.071). The stroke kinematic variables that changed between paces (p<0.05) were the duration of the entry, pull, push, hand exit and recovery phases; the elbow angle at the end back position and the push phase range; total shoulder and hip roll; the sum average vertical displacement of the foot; the time to max vertical and lateral displacement of the finger; the time at max right elbow extension; the average VCOMHor, Min VCOMHor and Max VCOMHor. The stroke kinetic variables that changed between paces (p<0.05) were the Min accCOM, Max accCOM, range of accCOM, min forceCOM and max forceCOM. Other variables approached significance between the paces such as the entry elbow angle (p=0.084), the max right elbow extension (p=0.056), the finger lateral range (p=0.067) and the time to max accCOM (p=0.079). The SG displayed shorter durations of the pull and push phases than the DG for both paces, which was linked to the faster horizontal velocity and/or vertical acceleration of the hand. The sequencing order of the shoulders and hips changed between groups and paces, which was speculated to be controlled by the magnitude of the leg-kick. The main changes between paces were the greater magnitude of elbow angle at both the end back position and the push phase range, which contributed to the adjustment of kinetic variables. SL, SF, SI, Vav and the duration of the all the stroke phases changed between sprint and distance pace in order to meet the physiological requirements of the race distance. The prolonged duration of the entry phase, when distance swimming, resulted in a delayed attainment of the catch position and maximum stroke depth. Moreover, the magnitude of shoulder and hip roll increased at distance compared to sprint pace, which in turn influenced the magnitude of average vertical and range of lateral displacement of the finger between paces. In conclusion, contrary to the literature, SG and DG differed only with respect to the duration of the pull and push stroke phases and the sequencing order of the shoulders and hips. All swimmers adjust the majority of kinematic and kinetic variables depending on the swim pace in order to optimise performance for that race distance.
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Hanaki-Martin, Saori. "THE EFFECTS OF SEAT POST ANGLE IN CYCLING PERFORMANCE." UKnowledge, 2012. http://uknowledge.uky.edu/khp_etds/1.
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Triathlon involves three different modes of endurance events, swim, bike and run, consecutively. Transitions between events are critical to be successful in the sport; however, many triathletes report impaired running performance due to adverse residual effects from cycling. One of the strategies that triathletes use to manage the adverse effects is to use a bicycle with a more vertical seat post angle. There is limited evidence that support the effectiveness of such bicycle geometry, but many of these studies lacks ecological validity.
Twelve triathletes and cyclists completed a 20-km simulated course with instrumentations for 3D motion, kinetic, and electromyographic analyses under two different seat post angle settings: shallow (ROAD) and steep (TRI). Series of paired-t tests were used for statistical analysis.
Results indicated cycling mechanics between two seat post angle conditions were similar; however, the steep condition resulted in time-delay in muscle activation and pedal force application. There was no significant difference in cycling performance. The athletes were able to retain relatively consistent pedaling techniques with modification of seat post angle.
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Churchill, Sarah. "Biomechanical investigations of bend running technique in athletic sprint events." Thesis, University of Bath, 2012. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.557811.
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For sprint events longer than 100 m, more than half the race is run on the bend, yet bend sprinting has received little attention in biomechanics literature. The aim of this thesis was to understand the effect of the bend on maximal effort sprint performance and technique, using bend radii and surfaces typical of outdoor competition. Three empirical studies were undertaken with experienced bend sprinters. Initial 3D kinematics investigations revealed an approximately 5% velocity decrease on the bend compared to the straight. However, step characteristic changes contributing to this reduction were different for the left and right steps. For the left step there were significant decreases in step frequency (p < 0.05), due to increased ground contact time, which agreed with previously proposed theoretical models. For the right step, however, a significantly reduced flight time resulted in a significant reduction in step length (p < 0.05). Maintaining step length and an ‘active touchdown’ were closely related to an athlete’s ability to better maintain straight line velocity on the bend. Generally, velocity decreased as bend radius decreased, with mean differences of up to 2.3% between lanes 8 and 2. However, changes to athletes’ technique due to different lanes were not conclusive. Ground reaction forces revealed between-limb differences during bend sprinting. Furthermore, frontal plane forces were up to 2.6 times larger on the bend than on the straight. Overall, asymmetries were identified between left and right steps for several performance, technique and force variables, suggesting that bend sprinting induces different functional roles between left and right legs, with the left step contributing more to turning to remain on the bend trajectory. The differences in kinematic and kinetic characteristics between the bend and straight, and between-limb asymmetries mean that athletes should apply the principle of specificity to bend sprinting training and conditioning, without sacrificing straight line technique.
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Jin, Li. "KINEMATIC AND KINETIC ANALYSIS OF WALKING AND RUNNING ACROSS SPEEDS AND TRANSITIONS BETWEEN LOCOMOTION STATES." Thesis, University of Oregon, 2018. http://hdl.handle.net/1794/23912.
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DISSERTATION ABSTRACT
Li Jin
Doctor of Philosophy
Department of Human Physiology
March 2018
Title: Kinematic and Kinetic Analysis of Walking and Running across Speeds and Transitions between Locomotion States
Walking and running are general locomotion activities for human beings. Basic gait patterns and whole body center of mass (COM) dynamic patterns are distinctly different between them. Lower extremity joint mechanics patterns could reflect musculoskeletal coordination characteristics. Change of locomotion tasks and speeds can affect lower extremity joint kinematic and kinetic characteristics, and progression of age may also affect these characteristics. Little is known about change of locomotion tasks and speeds effects on lower extremity joint level kinetic characteristics, and whether there is a connection between COM system and lower extremity system. To address this, twenty healthy subjects were recruited to participate in a series of treadmill tests, including walking (0.8 – 2.0 m/s, with 0.2 m/s intervals), running (1.8 – 3.8 m/s, with 0.4 m/s intervals) and gait mode transition from walking to running, and from running to walking (between 1.8 – 2.4 m/s, 0.1 m/s2). Three-dimensional kinematic and kinetic data were collected in all locomotion tests and used to calculate and analyze outcome variables for lower extremity joints and the COM system across different conditions. Results indicate that change of locomotion speeds significantly affect joint level kinetic characteristics within both walking and running locomotion states. Different locomotion task demands (walking vs. running) require fundamental alteration of lower extremity joint level kinetic patterns, even at the same locomotion speed. Progression of age also affects lower extremity joint level kinematic and kinetic patterns in walking and running across speeds. Additionally, stance phase an energy generation and transfer phenomenon occurred between the distal and proximal joints of the lower extremity in both walk-to-run and run-to-walk transitions. Lastly, a connection exists between whole body COM oscillation patterns and lower extremity joint level kinetic characteristics in running. These findings serve to further clarify the mechanisms involved in change of locomotion tasks and speeds effects on lower extremity joint kinetic patterns, and further establish a connection between the COM system and the lower extremity system. These findings may be beneficial for future foot-ankle assistive device development, potential optimization of gait efficiency and performance enhancement.
This dissertation includes previously published and unpublished coauthored material.
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Sha, Zhanxin. "Kinetic and Kinematic Properties of D-I Male Sprinters." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etd/2468.
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The purpose of the study was to explore and determine kinetic and kinematic variables that related to D-I male sprinters maximal running velocity performance. The current study was separated into 3 individual chapters: 1.) Kinematic analysis magnitude of acceleration for braking and propulsion phases during foot contact phase at maximal speed sprinting; 2.) Using kinetic isometric mid-thigh pull variables to predict D-I male sprinters’ 60m performance; 3.) Relationship of whole and lower body angular momentum cancellation during terminal swing phase to sprint performance.
Methods: for sprint measurement all the athletes were participated 2 trials of 100% effort running through 60 meters. The sprint time was measured by an electronic timing gate system. The electronic timing gate system was placed at every 10 meter intervals from the start line for 60 m. Six cameras were placed between 50 m and 60 m for kinematic data collection and analysis. Volume captured by the cameras is 7.5 m long, 1.2 m wide, and 1.95 m high. Reflective markers were attached on the body landmarks based on Vicon Nexus full body plugin model. The strength assessments were performed in a customized power rack, and kinetic values were collected via a dual force plate setup (2 separate 91 cm x 45.5 cm force plates, Roughdeck HP, Rice Lake, WI). The position for each isometric pull was established before each trial using goniometry, with each bar height corresponding to a 125±5º knee angle and a near-vertical trunk position.
Results: current study partially support previous assumption that fast sprinters can minimize braking phase during foot contact phase when they are running maximal velocity. However, those minimizing effects did not impact maximal running velocity performance. Second, the study showed that fast sprinters can produce greater force during a short period of time than slower sprinters. Moreover, a certain trend of statistical significance was observed from the third study that angular momentum cancellation between lower bodies at frontal plane may be related to maximal running velocity performance.
Discussion: the current study confirmed that fast sprinters can produce greater force in a short period time. However, the current study did not show statistical significance of angular momenta cancellation and sprint performance. Only a level of trend was observed. Thus, further study should examine sprinters with different training background, especially elite level sprinters is definitely needed.
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洪克賢 and Newman Hung. "Recovery kinetics in Chinese children with simple repaired congenital heart disease." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31257227.
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Hung, Newman. "Recovery kinetics in Chinese children with simple repaired congenital heart disease /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B23425386.
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Long, Ashley S. "The effects of a functional fatigue protocol on landing kinetics and kinematics of the lower extremity /." Full text available from ProQuest UM Digital Dissertations, 2005. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1320933691&SrchMode=1&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1197920031&clientId=22256.
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Schutte, Kurt Heinrich. "The effect of minimalist shoe training on lower limb kinematics and kinetics in experienced shod runners." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71791.
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Thesis (M Sport Sc)--Stellenbosch University, 2012.ENGLISH ABSTRACT: Limited data exists on a transition process of minimalist shoe running, warranting longitudinally designed studies. The primary aim of this study was thus to determine whether lower limb kinematics can be adapted, whether vertical average loading rate (VALR) can be attenuated, and whether lower limb joint moments can be altered by either novice or short-term (seven-week) minimalist shoe training. Ten experimental (EXP) habitually shod male endurance runners (age 24.10 ± 1.74; weekly training mileage 29.36 ± 8.51 km; BMI: 22.83 ± 8.55 kg/m2) volunteered to participate in a seven-week minimalist shoe transition programme. Eleven age and training matched control participants (CONT) (age 24.00 ± 2.18; weekly training mileage 24.90 ± 3.30 km; BMI: 23.78 ± 6.12) continued to run in their usual running shoes during the intervention period. All participants were provided with a pair of Vibram Fivefingers ® (VF). The VF intervention started at ~ 11% to 22% and ended at ~ 52% to 132% of the participants‘ usual shod training distance, determined by subjective lower limb comfort ratings. Lower limb biomechanics for barefoot: BF, minimalist: VF, and shod: SH were recorded with an eight-camera Vicon ® motion capture system, synchronized with a Bertec ® force plate, both prior to and after the transition programme. Twelve running trials at self-selected speeds were recorded bilaterally for each shoe condition. An inverse dynamic approach was used to calculate lower extremity joint moments. Primary parameters of interest were kinematic: step frequency (steps/min), step length (m), footstrike angles (FSA, degrees), strike index (SI,%); average vertical loading rate (VALR, BW/S) and sagittal and frontal plane peak joint moments (Nm/kg.m) of the ankle, knee and hip. At pre-testing, the results showed that for VALR, VF running was significantly higher than SH running but significantly lower than BF running (P < 0.05). Statistically significant shorter step lengths, higher step frequencies, greater plantar-flexion FSA, higher strike index, greater knee flexion FSA, and greater ankle inversion FSA were seen in BF and VF conditions compared to SH (P < 0.05). Statistically higher plantarflexion moment peak (PFM) while lower ankle dorsiflexion moment peak (DFM) and knee abduction moment peak (KAM) was found while BF and VF than SH running. The only statistically significant effect of the VF training intervention on kinematics was that of higher step frequency for the SH condition (P < 0.05), and greater inversion FSA in the BF condition. A trend was seen for the EXP group to increase VALR (P > 0.05). Ankle PFM peak significantly increased, while knee extensor moment peak (KEM) peak significantly decreased for the EXP group only (P < 0.05). Contrary to the initial hypothesis, novice or short-term VF training did not result in significantly attenuated VALR. However, alterations in joint moments suggest a shift in the distribution of external loads due to the VF training. Insufficient kinematic adaptation with VF training could be attributed to inability to sense higher VALR or due to greater perceived ratings of calf-Achilles discomfort, and may indicate that more than seven-weeks are required to transition and adapt to VF running.
AFRIKAANSE OPSOMMING: Beperkte data is beskikbaar oor die oorgangs fase van hardloop met minimalistiese skoene, langtermyn studies is dus nodig. Die primêre doel van die studie is om te bepaal of gemiddelde vertikale ladingstempo (VALR) verminder kan word en onderste-ledemaat gewrigsmomente aangepas kan word deur ‗n korttermyn oefenprogram in minimalistiese skoene. Tien experimentaal (EXP) manlike uithouvermoë hardlopers (ouderdom 24.10 ± 1.74; weeklikse oefen afstand 29.36 ± 8.51; BMI: 22.83 ± 8.55) wat gewoonlik in skoene hardloop het vrywillig ingestem om aan die sewe week minimalistiese-skoen oorgangsprogram deel te neem. Elf kontrole deelnemers wat gepas is volgens ouderdom en oefening, (ouderdom 24.00 ± 2.18; weeklikse oefening 24.90 ± 3.30 km; BMI: 23.78 ± 6.12 kg/m2) het in hulle gewone oefenskoene bly hardloop. Alle deelnemers het ‗n paar Vibram Fivefingers ®-skoene ontvang. Die VF intervensie het begin met ~ 11% tot 22% en geeinde met ~ 52% tot 132% van die deelnemers gewone afstande in SH. Biomeganiese aspekte van die onderste ledemate vir kaalvoet: BF, minimalisties: VF, en skoene: SH is deur middel van ‗n agt-kamera Vicon ® bewegingsisteem gesinkroniseer met ‗n Bertec ® kragplatform, voor en na die oorgangsprogram bepaal. Twaalf hardloop-pogings teen ‘n self-bepaalde spoed is bilateraal vir elke skoenkondisie gemeet. ‗n Omgekeerde dinamiese benadering is gebruik om die gewrigsmomente van die onderste ledemate te bepaal. Die primêre parameters van belang was kinematies: treefrekwensie, treelengte, voettrefhoeke (FSA), tree-indeks (SI); gemiddelde vertikale ladingstempo (VALR), en sagittale en frontale vlak piek gewrigsmomente van die enkel, knie en heup. By voor-toetsing, die resultate toon aan dat vir VALR, VF-hardloop betekenisvol hoër was in vergelyking met SH-hardloop, maar betekenisvol laer was in vergelyking met BF-hardloop (P < 0.05). Statisties beduidende korter tree, hoër treefrekwnesie, meer plantaarfleksie FSA, hoer ―strike index‖, meer kniefleksie FSA, en meer enkel inversie FSA is gevind in die BF en VF kondisie in vergelyking met SH (P < 0.05). Statistiese betekenisvol hoër plantaarfleksiemoment pieke (PFM), en minder enkel dorsiefleksiemoment pieke (DFM) en knie abduksiemoment pieke (KAD) was gevind by BF- en VF- hardloop in vergelyking met SH-hardloop (P < 0.05) Die enigste statistiese betekenisvolle verskil in die kinematika van die VF intervensie was ‗n hoër tree frekwensie vir die SH kondisie (P < 0.05), en groter enkel inversie FSA in die BF kondisie. Die EXP groep neig om ‗n verhoging in VALR te hê (P > 0.05). ‗n Aansienlike verhoging is gevind in piek enkel PFM, terwyl piek knie KEM statisties wesenlik verlaag het in die EXP groep (P < 0.05). In teenstelling met die oorspronklike hipotese het onmiddellike en 'n korttermyn VF oefenprogram nie 'n bekenisvolle effek op VALR vermindering nie. Sommige veranderings in gewrigsmomente suggereer dat 'n verplasing in die verspreiding van eksterne ladings plaasvind as gevolg van die VF oefening. Die onvoldoende kinematiese aanpassing kan moontlik toegeskryf word aan die onvermoë om hoër VALR waar te neem, of as gevolg van die hoër waargenome lesings in kuit-Achilles ongemak. Dit kan aandui da 'n VF oorgang proses van meer as sewe weke vereis word om aan te pas aan.
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Uygur, Mehmet. "Kinematics and kinetics of unanticipated misstep conditions in gait implications for femoral fractures in the elderly /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 71 p, 2008. http://proquest.umi.com/pqdweb?did=1605148261&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Jia, Bochen. "Influence of Prolonged Sitting and Psychosocial Stress on Lumbar Spine Kinematics, Kinetics, Discomfort, and Muscle Fatigue." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/50546.
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Low back pain (LBP) is a common occupational problem and continues to be the leading cause of occupational disability. Among diverse known risk factors, sitting is commonly considered as an important exposure related to LBP. Both modern living and contemporary work involve increased sedentary lifestyles, including more frequent and prolonged sitting. At present, however, the causal role of sitting on LBP development is controversial due to the contribution of several moderating factors (e.g., task demands, duration of exposures, and presence of muscle fatigue). A few studies have assessed low back loads in seated postures, but none has investigated the effects of prolonged sitting or time-dependent variations on spinal structure and spinal loading. Adverse effects of muscle fatigue on low back pain are well documented, yet the specific relationship between muscle fatigue and sitting-related low back pain are not fully established. In addition to these fundamental limitations in our understanding of the physical consequences of sitting, there is also little evidence regarding the effects of task requirements on muscle fatigue and spine loading. Therefore, the main objectives of this work were, in the context of sitting, to: 1) develop and evaluate a method to assess paraspinal muscle fatigue using electrical stimulation; 2) develop and evaluate a method (model) to quantify biomechanical loads on the lumbar spine in a seated posture; and 3) quantify the effects of prolonged seated tasks on low back loads, body discomfort, and localized muscle fatigue (LMF). The primary hypothesis was that exposure to sitting-related LBP risks is influenced by task requirements and sitting duration.
A muscle stimulation protocol was developed to measure stimulation responses in the lumbar extensors. A stimulation protocol, which included one conditioning train along with three 16-second stimulation train at 2 Hz, was recommended as appropriate to measure those muscles potentially fatigued during prolonged seated tasks. A three-dimensional, sitting-specific, fatigue-sensitive, time-dependent, electromyography (EMG)-based biomechanical model of the trunk was developed to investigate the effects of seated tasks and time-dependent variations on lumbosacral loading during sitting. Reasonable levels of correspondence were found between measured and predicted lumbosacral moments under a range of seated tasks. Lastly, the effects of prolonged sitting and psychosocial work stress on low back were quantitatively identified. Only prolonged sitting significantly increased trunk flexion angles and led to muscle fatigue. Relatively weak correlations were found between subjective and objective measures, though the two fatigue measurement methods (based on EMG and stimulated responses) showed a good level of correspondence.
Overall, this work provides a quantitative assessment of biomechanical exposures associated with seated tasks. The methods developed in this work make a contribution in terms of measurement/modeling approaches that can be used to assess LBP-relevant risks during prolonged sitting. The results of this work provide a better understanding of the effects of prolonged sitting on the risk of developing sitting-related LBP. Finally, results regarding the influences of prolonged sitting and psychosocial demands can be used to guide future job design.
Ph. D.
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Clayton, Lindsay E. "The Effects of Fatigue on Lower Extremity Kinetics and Kinematics in Subjects with Known Ankle Instability." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/4056.
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The goal of this study was to evaluate biomechanical differences between healthy subjects and those with ankle instability during the gradual onset of lower extremity fatigue from a landing activity. An understanding of these differences is needed in order to prevent future injury to or further debilitation in individuals with ankle instability. A functional fatiguing activity was designed to focus fatigue on the quadriceps muscles, as those are the muscles most frequently fatigued during sport. Measures were taken throughout the progression of fatigue with a force plate and a motion tracking system and included vertical ground reaction force and lower extremity kinetics, kinematics, and energetics. The time required to reach self-reported fatigue and a balance assessment, the Star Excursion Balance Test, before and after the onset of fatigue was also recorded. Significant differences were observed between groups in peak ground reaction force, ground reaction force impulse, and frontal plane ankle joint impulse. Results indicated that subjects with ankle instability not only exhibited a different baseline for most measurements than normal subjects, but also managed the progression of fatigue differently. With this information and information from further studies, recommendations and/ or training schemes could be made and implemented to help those with ankle instability avoid recurrent injuries.
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Okamatsu, Hidefusa. "External Ankle Supports Alter Kinematics and Kinetics during Drop-Jump Landing and Forward-Jump Landing Tasks." Diss., North Dakota State University, 2014. https://hdl.handle.net/10365/27366.
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This research project was designed to understand the influence of excessively restricting ankle range of motion (ROM) on knee injuries, especially non-contact anterior cruciate ligament (ACL) tear. Participating in physical activity without injuries is important to maintain physically active life style and well-being. To prevent ankle injuries, external ankle supports (EAS) are widely used in sport settings by limiting frontal plane ankle ROM; however, the EAS also restricts sagittal plane ankle ROM that could increase the risk of non-contact ACL injury by intensifying the medial knee displacement (MKD) and ground reaction force (GRF). In this research, the effects of external ankle supports (EAS) on landing mechanics were investigated among 19 physically active college-aged females. Two research manuscripts report the results of this research project. The first manuscript investigated the effect of EAS on landing kinematics and kinetics during a drop-jump landing task. The results demonstrated the use of EAS altered the ankle displacement, total MKD, and vertical GRF; however, no relationship was observed between isokinetic plantar flexor strength and landing mechanics. The second manuscript compared the effect of EAS on landing kinematics and kinetics between drop-jump landing and forward-jump landing tasks. The result exhibited the use of EAS similarly affect ankle displacement, knee displacement, peak MKD in drop-jump landing and forward-jump landing tasks. However, the landing tasks affected the posterior GRF differently, and the EAS altered vertical GRF differently in the two landing tasks. Overall, excessively restricted ankle ROM changed the landing kinematics and kinetics, especially MKD and GRF during landing tasks. Our findings indicate that healthcare professionals should use EAS with care because the overly limited ankle ROM could increase the risk of non-contact knee injuries by increased MKD and GRF. Future research should include an examination of the effect of EAS on the magnitude of ACL strain, an assessment of the strength of the other muscles, an evaluation of the muscular activation during a landing task. These studies help understand the landing techniques and strength training to reduce the risk of non-contact ACL tear among physically active population.NDSU College of Human Development and Education
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Muslim, Khoirul. "Traditional Posterior Load Carriage: Ergonomic Assessment and Intervention Efficacy." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/23726.
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There is a high prevalence of musculoskeletal symptoms (MSS) among manual material handling (MMH) workers. However, limited investigations have been undertaken among one large group of workers using a particular MMH method called traditional posterior load carriage (PLC). Such load carriage is typically done without the use of an assistive device (e.g., backpack) in developing countries, and involves exposure to known risk factors for MSS such as heavy loads, non-neutral postures, and high levels of repetition. The current work was completed to investigate the characteristics of the PLC task and physical effects on workers, and to evaluate a practical intervention that may help improve the task. The first study investigated, through structured interviews with 108 workers, the types, prevalence, and impacts of MSS. PLC workers incur a relatively high MSS burden, primarily in the lower back, but also in the feet, knees, shoulders, and neck. These MSS were reported to interfere with daily activity, but only few workers sought medical treatment. Workers suggested several task improvements including the use of a belt, hook, or backpack/frame, and changes in the carriage method. The second and third study investigated, in a laboratory setting involving nine healthy males, the effects of load mass and size, and the use of a simple intervention, respectively, on factors related to low back pain risks during PLC. Increasing load mass caused increased torso flexion, lumbosacral flexion moment, abdominal muscle activity, and torso movement stability in the frontal plane. Increasing load size also caused higher torso flexion, peak torso angular velocity and acceleration, and abdominal muscle activity. Complex interactive effects of load mass and size were found on paraspinal muscle activity and slip risk. The intervention, involving a simple frame to support a load, and use with a higher load placement was found to be potentially beneficial as indicated by reduced lumbosacral moment and ratings of perceived discomfort in several anatomical regions compared to the traditional PLC. Outcomes of this research can facilitate future ergonomic guidelines and interventions to improve working conditions and occupational health and safety for PLC workers.Ph. D.
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Kim, Hyun. "Lower Extremity Neuromechanics During a Forward-Side Jump Following Functional Fatigue in Patients with Ankle Instability." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5976.
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Ankle instability (AI) and fatigue impair neuromuscular control as well as dynamic joint stability of the lower extremity. No one has comprehensively examined the effects of AI and fatigue on neuromechanics of the lower extremity during a functional activity. Deficits associated with AI and fatigue could be additive in increasing the risk for injury in patients with AI. PURPOSE: To examine the interaction of AI and fatigue on lower extremity muscle activity, kinematic, and kinetic patterns during a forward-side jump. METHODS: 25 AI (23.3 ± 1.9 yrs, 176.5 ± 10.5 cm, 70.9 ± 11.4 kg), and 25 matched control subjects (23.7 ± 2.5 yrs, 175.0 ± 10.8 cm, 70.3 ± 12.8 kg) were categorized according to the Foot and Ankle Ability Measure (FAAM) (ADL: 84.3 ± 7.6%, Sport: 63.6 ± 8.6%) and the Modified Ankle Instability Instrument (MAII) (3.7 ± 1.2). Fifty-nine reflective markers were place over anatomical landmarks and eight electromyography (EMG) electrodes were placed on tibialis anterior (TA), peroneus longus (PL), medial gastrocmedius (MG), medial hamstring (MH), vastus lateralis (VL), adductor longus (AL), gluteus medius (GMed), and gluteus maximus (GMax) muscles in the involved leg. Subjects performed five forward-side jumps on a force plate before and after functional fatiguing exercises. To induce fatigue, subjects began 5-min incremental running on a treadmill between 5 and 6 mph. Next, subjects performed 20-second lateral counter movement jumps (CMJ), and 20 vertical CMJs. After each fatigue cycle, subjects performed one max vertical jump. Subjects repeated three exercises until Borg's rating of perceived exertion (RPE) reached 17 and the vertical jump height fell below 80% of their max jump height. Functional analysis of variance (FANOVA) (p < 0.05) was used to evaluate differences (a group by fatigue interaction) between two conditions (pre- vs post-fatigue) in each group (AI and control) for lower-extremity kinematic, kinetic and neuromuscular patterns. Pairwise comparison functions as well as 95% confidence interval (CI) bands were plotted to determine specific differences. If 95% CI bands did not cross the zero line, we considered the difference significant. RESULTS: Compared to the control group, the AI group demonstrated less range of dorsiflexion, knee and hip flexion motions during early phase of landing after fatigue. For sagittal-plane hip kinetics, subjects with AI decreased the hip extension moment while control subjects increased hip extension moments during landing following functional fatiguing exercise. The AI group showed less reduction of anterior-posterior ground reaction force (AP GRF) during transition phase of a forward-side jump after fatigue compared to control subjects. The AI group decreased EMG amplitude of PL, MH, and GMed while increased VL and GMax during landing after fatigue compared to control subjects. CONCLUSION: AI subjects demonstrated greater impairments in neuromechanical control patterns than a matched control group during a sport movement as fatigue progressed. Compared to AI group, control subjects showed a coordinated joint control strategy after fatigue, increasing joint angles from distal (ankle) to proximal (hip) joints by increasing hip extensor moments during landing from a forward-side jump in an attempt to reduce ground impact force. EMG alterations were consistent with patterns observed in injured patients, which may predispose patients to poor positions associated with lower extremity joint injury. These interactions between neuromuscular fatigue and AI may predispose individuals to lower extremity injuries.
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Miguel, Andres Israel. "Contribution of the anconeus muscle to the elbow kinematics : range of motion of 90° of flexion-extension and pronation-supination." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/contribution-of-the-anconeus-muscle-to-the-elbow-kinematics-range-of-motion-of-90-of-flexionextension-and-pronationsupination(457e1132-6600-4954-ae28-c8c7b9553247).html.
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The anconeus, a small triangular muscle positioned on the posterolateral part of the elbow joint, has been the subject of considerable research without a satisfactory conclusion being reached regarding the role it plays during normal elbow kinematics. The aim of this investigation was to elucidate the function of the anconeus muscle and find the relative contribution that it makes to elbow kinematics by examining relative electrical muscle activity and elbow kinematics both before and after anconeus defunctioning carried out using a local anaesthetic (lidocaine). The study was performed through an examination of the myoelectric activity of the representative elbow flexor and extensor muscles (biceps brachii and triceps brachii) and the elbow kinematics and kinetics. Right-handed, healthy volunteers performed elbow flexion-extension and supination-pronation movements in both horizontal and sagittal planes before and after blocking of the anconeus. The kinematics and kinetics of the elbow were assessed using inertial sensors, and muscle electrical activity was recorded using surface electromyography. In the following stage of the study, the anconeus muscle was blocked through an injection of lidocaine and then the flexion-extension and pronation-supination movements were repeated. The relative electrical activity results from the anconeus before blocking clearly indicate that the activity of the muscle was higher during the extension portion of the flexion-extension cycle, suggesting that it behaves as an extensor muscle. However, from the paired sample t-test analysis, it was found that blocking of the anconeus had no effect on the kinematics and kinetics of the elbow, including the angular velocity, net torque, power and net joint work. Moreover, the angular velocity data for the elbow, before and after the blocking for all movements, showed a linear trend with slopes and Pearson's correlations close to unity, indicating no apparent difference on the elbow kinematics. In addition, the relative electrical activity of the biceps and triceps brachii muscles did not alter significantly following blocking of the anconeus. These findings suggest that the anconeus muscle is a relatively weak elbow extensor as it is likely that the small contribution that the anconeus provides during extension before blocking is compensated by the triceps brachii after the anconeus is deactivated. In order to provide additional weight and support to the findings of the experimental study, a computational model of the elbow joint was created in Abaqus CAE with the aim of investigating the contribution of the anconeus during the flexion-extension motion. In particular, the effect on the range of motion and contact area of the elbow joint was investigated both before and after anconeus blocking. The analysis was done in a range of motion of 90°, starting with the elbow extended 30° and ending flexed 120°. The elbow joint model considered cortical bone, trabecular bone, cartilage, collateral ligaments, the anconeus, biceps brachii and triceps brachii. The results of the investigation indicated that the anconeus muscle does not produce a significant change in the range of motion and contact area in the articulation, an outcome that supports the findings of the experimental investigation.
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Alfattani, Rami. "Design of Shape-Morphing Structures Consisting of Bistable Compliant Mechanisms." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7725.
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This dissertation presents a design concept for shape-morphing structures that have two stable configurations. The design concept defines the methodology of transforming a planar structural shape into spatial structural shape using bistable compliant mechanisms. Bistable complaint mechanisms are used to achieve structural stable configurations. The dissertation incorporating geometrical relationships for the mechanisms that form the primary structure described in step-by-step process. This dissertation implements the design layouts for designer to creating shape-morphing structures including origami. The novel contribution of the work is classified in three models. The first model presents a methodology to induce bistability behavior into an origami reverse fold and partially spherical compliant mechanism. The second model presents the design and development of a bistable triangle-shaped compliant mechanism with motion limits and dwell behavior at the two stable configurations. This mechanism can be arrayed to create shape-morphing structures. The third model presents a design and development for a collapsible bistable compliant mechanism used for a shape morphing lamina-emergent frustum. Finally, physical prototypes of all models are presented as proof of concept.
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Whissell, Elizabeth. "Motion Pattern of the Healthy Yoga Practitioner – Kinetics and Kinematics of the Lower Extremity During Three Yoga Postures and Comparison to Three Activitiesm of Daily Living." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33174.
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The purpose of this study was to establish a motion pattern by characterizing the kinetics and kinematics associated with the hip, knee and ankle joint of a group of healthy yoga teachers when performing three yoga postures and comparing them to three activities of daily living (ADL). A group of experienced female yoga practitioners (n = 13), with a minimum of 5 years teaching experience, between the ages of 20 to 45, performed the Lunge, Warrior II, and Triangle poses starting from Downward Dog. The kinetic and kinematic data of the yoga practitioners was collected when performing yoga postures. The step length, joint angles, range of motion (ROM), joint moments, and angular impulse in sagittal and frontal plane were studied for the hip, knee and ankle during performance. The data were averaged, descriptive statistics of the measures were obtained, and results for each posture as well as for the average yoga practice were presented in tables and figures with standard deviation. The percentages of change and effect sizes were calculated to compare yoga movements to ADL. The stride lengths were similar in the Lunge (1.98m), Warrior II (1.51m), and Triangle (1.43m). The motion patterns of the Lunge and the Warrior II poses follow similar joint angle and joint moment, and angular impulse patterns, whereas the Triangle pose creates distinctly different patterns in most joints and planes. In the Lunge and Warrior II poses, the knee joint reaches a maximal flexion angle of 73.76° and 67.69° respectively, 18% to 32% less than what is classically instructed in a yoga class. The knee reached 9.5° of extension while in Triangle pose. The hip contributed 50-70% of the angular impulse in the lower limb in all three yoga movements. When comparing to ADL, ROM was only greater in the hip in of sagittal plane motion and in the knee if frontal plane motion, and most of the joint moments of the lower extremity were notably smaller in ADL for the minimal values and notably larger for the maximal values in yoga. In conclusion, this is first time to establish the kinematics and kinetics motion patterns of three yoga movement which become a basis for further studying yoga biomechanics and its application. Moreover the motion pattern data suggests that yoga experts do not yoga as practice the Lunge and Warrior poses as classically described in yoga book for the knee and Triangle pose may place the knee in a precarious alignment. Yoga has high demanding to hip strength and ROM, which may help to improve hip strength and subsequently benefit to dynamic stability in gait.
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Ozkaramanli, Deger. "Influence of Different Designs of High-Heeled Shoes on Kinematics, Kinetics, and Muscle EMG of Female Gait." Scholarly Repository, 2007. http://scholarlyrepository.miami.edu/oa_theses/109.
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Many studies have investigated the differences in gait patterns with increasing heel height. The purpose of this investigation is to study the differences in gait patterns when wearing stiletto and wedge type high-heeled shoes with different heel designs versus barefoot walking. A Vicon 512 Motion Analysis system and four Kistler force plates were used to record changes in lower-extremity joint kinetics and kinematics in three conventional planes of motion. Additionally, electromyography (EMG) was used to assess differences in the behavior of selected muscles under each condition. Results showed that wearing of the high-heeled shoes increased vertical ground reaction forces during both early and late stance. Ankle dorsiflexion moment was significantly greater in stiletto type high-heeled shoes compared to wedge and barefoot conditions. A reduction in ankle plantar flexor moment and ankle power was observed between high heeled shoe conditions and barefoot walking during late stance. An increase in the integrated EMG values of soleus and gastrocnemius lateralis muscles was noted during stance, while gastrocnemius medialis integrated EMG values decreased in both type of high heeled shoes. Integrated EMG of tibialis anterior was also decreased throughout swing phase due to more plantarflexed foot position. Knee extension moment during late stance increased significantly in both shoe conditions. Additionally, rotational hip moments were significantly different in high-heeled shoes compared to barefoot condition during both early and late stance. Peak plantar/dorsiflexion angles as well as maximum knee flexion angles differed significantly during stance phase of walking between all conditions. Quadriceps activity was increased and prolonged throughout stance and full gait cycle to control knee flexion. There was a trend towards more severe biomechanical changes occurring in stiletto type high-heeled shoes in majority of the dependent variables. Future research should focus on the biomechanics of female gait using different designs of high heeled shoes considering the weight, age, and experience of the wearer. Furthermore, utilizing multi-segmental foot models in order to assess kinematic changes occurring in the entire foot segment and recruitment of triceps surae muscle group will provide more insight to instability of high-heeled gait in different designs of high heeled shoes.
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Graham-Smith, Philip. "The kinematics and kinetics of jumping for distance with particular reference to the long and triple jumps." Thesis, Liverpool John Moores University, 1999. http://researchonline.ljmu.ac.uk/5069/.
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The common aim of the long and triple jumps is to attain maximum horizontal distance from the front of the take-off board. This is achieved by converting some of the horizontal velocity developed in the approach run into vertical velocity at take-off. The aim of this thesis was to examine a theoretical model and to identify kinematic and kinetic factors that facilitate the generation of vertical velocity in the long and triple jump take-offs. A pivot mechanism was defined to act between touch-down and the instant the centre of mass was directly above the toe of the support foot. This mechanism was found to be the largest contributor to the gain in vertical velocity in all take-offs, accounting for 83.0% in the long jump and 63.7%, 69.8% and 70.7% in the hop, step and jump take-offs. The contribution of the pivot to the gain in vertical velocity at take-off in the long jump was significantly greater than in each of the triple jump take-offs, (all P<0.002). A relative momentum approach was used to determine the contribution of the free limbs to the generation of vertical velocity. In the long jump, the free limbs made a 10.8% contribution to the gain in vertical velocity, compared to 12.2%, 19.0% and 19.0% in the triple jump take-offs. Multiple regressiona nalysesw ere used to identify factors relating to the generationo f vertical velocity in the long jump (n=14). The greatestg ains in vertical velocity were associatedw ith techniquest hat emphasiseda low centre of mass and extended knee joint at touch-down and the ability to resist knee flexion in the compression phase, R2=72.7%. The greatest losses in horizontal velocity were associated with excessiveh ip adduction, less hip extensiona nd greater increasesin height from touchdown to take-ofll R2=84.5%. Ground reaction forces and net joint moments were measured during short approach running jump tests. Peak vertical impact forces were greater in simulated 'drop' take-offs, 5080 N, compared to those experienced in 'flat' approach take-offs, 3250 N, (P=O. 002). Peak horizontal braking forces were 1800 N in both types of take-off. However, the peak net joint moments about the ankle, (403 N. m and 387 N. m), knee (233 N. m and 296 N. m) and hip (292 N. m and 249 N. m) were similar between the 'flat' and 'drop' take-offs. This suggests that athletes adapt their technique in the 'drop' take-off to distribute the larger forces effectively and to keep the net joint moments within controllable limits. Results indicated that strength about the ankle joint was particularly important in both types of take-off, but depending on the athlete's technique strength about the knee and hip are also vital. Greater flexion of the knee joint at touch-down and maximum knee flexion were found to be associated with greater average knee moments, R2=30.8% and 75.5% respectively, and greater angles of leg placement were moderately associated with greater average hip moments, R2=23.5%. In conclusion, this thesis has provided a greater insight into the kinetics and kinematics of jumping for distance. It has quantified the contribution made by the pivot mechanism and the free limbs to the generation of vertical velocity, and has assessetdh e demandso n the musculoskeletal system in terms of ground reaction forces and net joint moments. The results indicate that elite performers cannot rely on speed alone, and that strength and technique are major factors of successful performance.
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Rosén, Johanna. "Biomechanical differences between elite able-bodied kayakers and elite para-kayakers during paddling : The second and third step of creating the new Paralympic classification system." Thesis, Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:gih:diva-3897.
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Aim The aim of the study was to examine the differences between able-bodied athletes (AB) and three para-athlete (PA) classes in three-dimensional range of motion (RoM) for the major joints of the body, and to define which joint angles are correlated with power output during paddling on a kayak ergometer. An additional aim was to validate three new classification tests used in classification of Paracanoe athletes. This study was an integral part of developing a new evidence-based classification system for Paracanoe which was accepted by the International Paralympic Committee in 2015. Method 41 PA (13 F and 28 M; 35 ± 9.0 years, 70.6 ± 12.5 kg, 1.74 ± 0.12 m) and 10 AB (4 F and 6 M; 22 ± 3.5 years, 78.3 ± 10.2 kg, 1.79 ± 0.06 m) participated in the study. Three-dimensional kinematic data was recorded using an optoelectronic system containing 12 infrared cameras capturing reflective markers placed on the participants, the paddle and on the force transducers. Force was measured at the paddle to enable calculations of power output. The kinematic and kinetic data were collected during paddling on the kayak ergometer at incremental intensities starting at a low intensity level (50 W). The athletes then increased intensity with 50 W up to a high intensity level which was defined as the highest level the athlete could maintain with good technique for 20 stroke cycles. The athletes were then asked to paddle at a maximal level. The kinematic and kinetic data were imported into Visual 3D and MATLAB where all calculations were made. Results There were significant differences between the AB and the three PA classes for joint angles in the shoulder (e.g. flexion/extension and internal/external rotation, AB>PA), trunk (trunk rotation and trunk flexion, AB>PA) and leg (hip, knee and ankle flexion AB>PA) during paddling. Significant positive correlations were seen for both men and women between power output and trunk rotation RoM, hip, knee and ankle flexion RoM and in maximal trunk flexion during paddling. A positive correlation was also seen between the newly developed classification tests and the RoM values and power output. Conclusion This study showed that the RoM of the trunk and legs are positively correlated with power output during paddling on a kayak ergometer and that there is a significant difference between the AB and the PA classes in trunk and leg RoM. The results also showed that the newly developed classification tests are valid tests to use in classification of Paracanoe athletes.Syfte och frågeställningar Syftet med studien var att undersöka skillnaderna mellan icke funktionsnedsatta idrottare (AB) och tre klasser av funktionsnedsatta idrottare (PA) i tredimensionellt rörelseomfång (RoM) i samtliga större leder i kroppen, och att definiera vilka leder som korrelerade med power output vid paddling på kajak ergometer. Ett ytterligare syfte var att validera tre nya klassificeringstester för klassificering i Parakanot. Denna studie var en viktig del vid utvecklingen av ett nytt evidensbaserat klassificeringssystem för Parakanot vilket blev accepterat av Internationella Paralympiska Kommitteen under 2015. Metod 41 PA (13 K och 28 M; 35 ± 9.0 år, 70.6 ± 12.5 kg, 1.74 ± 0.12 m) och 10 AB (4 K och 6 M; 22 ± 3.5 år, 78.3 ± 10.2 kg, 1.79 ± 0.06 m) deltog i studien. Tredimensionell kinematisk data samlades in med ett optoelektroniskt system innehållandes 12 infraröda kameror som registrerade reflekterande markörer som var fäst på försökspersonerna, på paddeln och på kraftgivarna. Kraft mättes vid paddeln vilket möjliggjorde beräkning av power output. Den kinematiska och kinetiska datan samlades in vid paddling på kajak ergometer på olika intensitetsnivåer och idrottarna startade på en låg intensitetsnivå (50 W). Idrottarna ökade sedan intensitet med 50 W upp till en hög intensitet vilket definierades som den högsta nivån som idrottarna kunde paddla stabilt på med bra teknik i 20 drag cykler. Idrottarna paddlade sedan på en maximal nivå. Den kinematiska och kinetiska datan importerades sedan till Visual3D och MATLAB där alla beräkningar utfördes. Resultat Det fanns en signifikanta skillnader mellan AB och de tre PA klasserna för ledvinklarna i skuldran (flexion/extension och inåt/utåt rotation, AB>PA), bålen (bål rotation och bål flexion, AB>PA) och i benen (höft, knä och ankel flexion, AB>PA) vid paddling. Det fanns en signifikant positiv korrelation för både män och kvinnor mellan power output och RoM i bål rotation, höft, knä och ankel flexion och i maximal bål flexion vid paddling. En positiv korrelation fanns även mellan de nyutvecklade klassificeringstesterna och RoM värdena samt power output. Slutsats Studien visade att bål- och benrörelsen är positivt korrelerat med power output vid paddling på kajak ergometer och att det är en signifikant skillnad mellan AB och PA klasserna i bål och ben RoM. Resultaten visade också att de nyutvecklade klassificeringstesterna är valida tester för användning inom klassificering av Parakanotister.
Kursen Projektarbete.
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Law, Nok-Yeung. "Kinetics and Kinematics of the Lower Extremity During Performance of Two Typical Tai Chi Movements by the Elders." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/23632.
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Tai Chi Chuan is a safe alternative for those who wish to improve balance and physical wellbeing. It is a popular form of exercise that is supported by a growing body of research aimed towards improving the health of a sedentary elderly population. The purpose of this study was to examine the biomechanical features of the lower extremity during performance of two Tai Chi movements, the “Repulse Monkey (RM)” and “Wave-hands in clouds (WHIC).” The study’s parameters included quantitative measures of the temporospatial, kinematic, and kinetic characteristics of the lower extremities. A group of experienced male Tai Chi practitioners (n = 15) between the ages of 65 to 75, performed “Repulse Monkey (RM)”, “Wave-hand in Cloud (WHIC)”, and forward walking. Three-dimensional (3-D) kinematic and kinetic data was collected using VICON motion analysis system with 10 infrared cameras and 4 force plates. The following variables were examined: stride width, step length, step width, single- and double-support times, centre of mass (COM) displacement, peak joint angles, range of motion, peak joint moments, time to peak moment, and ground reaction force (GRF). The differences in the measurements of the two Tai Chi movements were compared with walking using two-way ANOVA. The study’s results showed that the two Tai Chi movements elicit gentle and fluid changes to position of the upper body mass and the joints in the lower extremity. In terms of joint kinematics, the knee remained flexed throughout RM and WHIC. Unlike walking, RM had larger abduction and adduction angles at the knee joints and large plantar- and dorsiflexion ROM at the ankle. Reduced posterior, mediolateral, and vertical GRF were seen; the loading joints at the ankle and hip were gentle and smaller than walking. Varus/valgus moments were notably larger at the knee joint during RM and eversion moment was larger at the ankle joint during WHIC movement. A large, but slow loading rate at the knee joint has implication towards the viscoelastic properties of the knee. A better understanding of RM and WHIC would facilitate the improvement of balance, physical capacity, and joint flexibility for the elders.
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Lathrop, Rebecca Leeann. "Locomotor Training: The effects of treadmill speed and body weight support on lower extremity joint kinematics and kinetics." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1249676293.
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Castro, Flavio Antonio de Souza. "Determinantes do desempenho para a prova de 200m nado livre." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/11196.
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Características antropométricas, biomecânicas e fisiológicas são considerados fatores determinantes do desempenho em natação. A prova de 200 m nado livre apresenta condições energéticas singulares que oferecem interessantes desafios para nadadores, treinadores e cientistas do esporte. Os objetivos deste estudo foram identificar a importância de cada fator relacionado ao desempenho na prova de 200 m nado livre, e suas interrelações. Foram voluntários neste estudo 12 nadadores do sexo masculino (idade: 18,3 ± 2,9 anos; estatura: 174,3 ± 5,8 cm; envergadura: 181,1 ± 7,5 cm; massa corporal total: 66,4 ± 6,3 kg; somatório de quatro dobras cutâneas: 31,9 ± 8,2 mm), federados e nadando 37 ± 7 km por semana, cujo melhor tempo na prova de 200 m nado livre era 125,2 ± 2,7 s. Além das variáveis antropométricas, foram obtidos, de 200 m nado crawl, executados em piscina de 25 m, sob máxima intensidade, desempenho em s, transformados em valores pontuais (DESP), considerando o recorde mundial da prova como 1000 pontos e variáveis cinemáticas distância média percorrida por ciclo de braçadas (DC), freqüência média de ciclo de braçadas (FCL) e velocidade média de nado (VN), dos oito trechos de 25 m dos 200 m. Variáveis cinemáticas foram obtidas empregando-se um sistema digital para videogramatria. Antes da realização dos 200 m foram identificados o consumo de oxigênio (VO2r) e a concentração de lactato, ambos de repouso ([LAr]). Após os 200 m foram identificados o consumo de oxigênio pós esforço (VO2e), pelo método de retroextrapolação e o pico de concentração de lactato P[LA]. Para identificar os valores de VO2 foi utilizado um analisador de gases portátil e para os valores de [LA] um lactímetro portátil. Dos valores de VO2 e [LA] foram calculados os valores líquidos dos mesmos (VO2l e [LAL] e a energia total (Etot) gasta na realização dos 200 m. A realização de um teste de nado estacionário, de 30 s de duração, possibilitou a identificação do impulso total (IMP) e da taxa de variação do impulso (TIMP), com a utilização de célula de carga de tração. Foram calculados os coeficientes de variação (cv) das variáveis e aplicados testes estatísticos de medidas repetidas, de comparação de médias e modelos de regressão linear múltipla, estes em cinco modelos: antropométrico, cinemático, fisiológico, cinético e geral. O desempenho dos nadadores avaliados foi de 130,2 ± 2,8 s (711,8 ± 29,1 pontos). Respectivamente valores médios de DC, FCL e VN foram: 2,10 ± 0,11 m, 0,69 ± 0,07 Hz e 1,45 ± 0,11 m·s-1. Já valores de VO2l, [LA]L e Etot foram de, respectivamente, 55,5 ± 5,5 ·kg-1·min-1, 11,15 ± 1,17 mmol·l-1 e 67,2 ± 5,5 ml·kg-1·min-1. Valores de IMP e TIMP foram de, respectivamente, 2648,4 N·s e – 25,1 ± 3,7 N. No modelo geral de regressão linear múltipla entraram as variáveis que puderam, de modo significativo, explicar o desempenho nos modelos por grupos de variáveis (DC, cvVN, VO2l e IMP) exceto a envergadura (ENV), que não responde a estímulos de treinamento. O modelo geral conseguiu explicar até 72,2% da variação do DESP, com as variáveis DC e VO2l entrando de modo significativo no modelo de regressão múltipla (DESP = 67,09DC – 3,048VO2l + 733,4). De maneira geral, os resultados indicaram que envergadura, distância média percorrida por ciclo de braçadas e impulso total em nado estacionário de 30 s correlacionam–se positivamente com o desempenho, já o consumo de oxigênio líquido e o coeficiente de variação da velocidade média de nado, negativamente. Para o melhor desempenho na prova de 200 m nado livre, espera-se que o nadador apresente uma maior DC e um nado mais econômico.Anthropometrics, biomechanics and physiological characteristics have been considered determining factors of swim performance. Two-hundred meters freestyle event shows unique metabolic energetic conditions offering a challenge for swimmers, coaches and researchers. The aims of this study were to identify each performance determinant factor importance and its interrelations with the 200 m freestyle swimming event. Twelve male swimmers (age: 18.3 ± 2.9 years; stature: 174.3 ± 5.8 cm; arm limb span: 181.1 ± 7.5 cm; total body mass: 66.4 ± 6.3 kg; four skin folds sum: 31.9 ± 8.2 mm, weekly training 37.7 ± 7 km, best time in the event: 125.2 ± 2.7 s) participated in this study. In addition to anthropometrics variables were obtained, from the 200 m freestyle performed in a 25 m pool at maximal intensity, performance in seconds, transformed in points values (DESP) – considering the world record as 1000 points – and kinematics variables: mean stroke length (DC), stroke rate (FCL) and swimming velocity (VN) during all eight laps of the 200 m. A two dimension digital motion system was used to obtain the kinematics variables. Prior to the 200 m test resting oxygen consumption and lactate concentrations were determined. After the 200 m test post oxygen consumption, by the backward extrapolation method, and lactate concentration peak P[LA] were evaluated. To identify the oxygen consumption values (VO2) and the lactate concentration ([LA]) a portable respiratory gas analyzer and a lactate meter, respectively, were used. From the VO2 and [LA] were calculated the net values (VO2l and [LAL]) and the total expended energy (Etot) during the 200 m. A 30 s tethered swim test allowed for the evaluation of the total impulse (IMP) and the impulse variation ratio (TIMP). The coefficients of variation (cv) of the variables were calculated and applied statistical tests using repeat measurements, mean comparison and multiple linear regression models, in five different models: anthropometric, kinematics, physiological, kinetic and general. The swimmers’ performance was 130.2 ± 2.8 s (711.8 ± 29.1 points). DC, FCL and VN were: 2.10 ± 0.11 m, 0.69 ± 0.07 Hz e 1.45 ± 0.11 m·s-1, respectively. Whereas VO2l, [LAL] and Etot were, respectively, 55.5 ± 5.3 ml·kg-1·min-1, 11.15 ± 1.17 mmol·l-1 and 67.2 ± 5.5 ml·kg-1·min-1. IMP and TIMP values were, respectively, 2648.4 N·s e – 25.1 ± 3.7 N. On the general multiple linear regression model only the variables that could, in a statistical way, explain the performance on the variable group models (DC, cvDC, VO2l and IMP) were used, except for one’s arm limb span which will obviously not respond to any training stimulus. The general model explained up to 72.2% of the DESP variation with the DC and VO2l variables, by the multiply regression model (DESP = 67.09DC – 3.048VO2l + 733.4). The results indicated that arm limb span, mean distance covered per stroke cycle and the total impulse at 30 s tethered swim test showed a positive correlation with performance. Whereas net oxygen consumption and coefficient of variation of the mean swim speed presented a negative correlation. For a better performance during the 200 m freestyle is expecting a bigger DC and a more economical swim.
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Zhong, Yanlin [Verfasser]. "Three-dimensional kinematics and kinetics of the knee in posterior cruciate ligament reconstructed patients during daily activities / Yanlin Zhong." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2015. http://d-nb.info/1070819573/34.
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Iguchi, Junta. "The effect of sex and fatigue on lower limb kinematics, kinetics and muscle activity during unanticipated side-step cutting." 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/180626.
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Leach, Robert J. "The role of biomechanics in achieving different shot trajectories in golf." Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/26338.
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In golf, a range of shot types are necessary for successful performance, with driving and iron-play constituting the long-game. It is possible to vary long-game shots through altered trajectory, for example, by utilising right-to-left or left-to-right ball flight curvature, providing course management advantages. However, how golfers vary their biomechanics to achieve different trajectories is not scientifically understood. Therefore, the purpose of this thesis was to biomechanically investigate different trajectories hit with the same club. To investigate shot trajectories, accurate measures of performance were necessary. Launch monitors (TrackMan Pro IIIe and Foresight GC2+HMT) are bespoke technologies capable of tracking the clubhead and ball through impact. However, their accuracy for scientific research has not been independently validated. Therefore, a novel purpose-designed tracking method was developed using a three-dimensional optical tracking system (GOM). The accuracy of this method was validated and the system used as the benchmark to which the two launch monitors were compared through limits of agreement. The results showed, in general, the launch monitors were in closer agreement to the benchmark for ball parameters than clubhead. High levels of agreement were found for ball velocity, ball path, total spin rate and backspin. However, poorer agreement was shown for ball sidespin and spin axis as well as clubhead velocity, clubhead path and clubhead orientation. Consequently, the launch monitors were deemed unsuitable for inclusion in scientific research across a range of impact parameters. Draw and fade trajectories with a driver and draw, fade and low trajectories with a 5-iron were investigated biomechanically. The clubhead and ball were tracked using the optical method developed in this thesis. Key biomechanical variables (address position and whole-swing) were defined based on coaching theory. Statistically, analysis of variance (address) and principal components analysis (whole-swing), were used to compare draw against fade and low against natural trajectories. Multivariate correlation was used to identify swing pattern similarities between golfers. The group-level comparison showed draw-fade address differences whereby for draw trajectories, the ball was positioned further away from the target, the lead hand further towards the target and the pelvis, thorax and stance openness closed relative to the target line. Over the whole-swing, the draw when compared to the fade demonstrated a pelvis rotation, more rotated away from the target with later rotation; lumbar forward flexion, with slower extending in the downswing; lumbar lateral flexion, with more flexion towards the trail throughout and prolonged trail flexing through ball contact; thorax lateral flexion, with greater, slower lead flexing in the backswing and greater, more prolonged trail flexing in the downswing; pelvis translation further towards the target throughout, with earlier forward translation and centre of pressure, with an earlier, quicker, greater forward shift. Cluster differences were evident, with both Clusters I (57% of golfers with the driver) and II (71% of golfers with the 5-iron) showing greater, earlier thorax rotation towards the target and a tendency for greater lumbar forward flexion over the whole-swing (Cluster II) and backswing (Cluster I). For the group-level low-natural comparison, golfers positioned the ball further away from the target and their lead hand further towards the target for low trajectories. Further, Cluster IV (45% of golfers), narrowed their stance width and laterally flexed their thorax towards the lead, for the same trajectories. Over the whole-swing, the low when compared to the natural showed the pelvis translated towards the target throughout, with later, lesser forward shift for the low trajectories. Furthermore, centre of pressure displayed a greater forward shift for the same shots. Finally, both clusters (Cluster III 36% of golfers and Cluster IV) differed in lumbar forward flexion when playing low trajectories; over the backswing, Cluster III extended, whereas Cluster IV flexed. Cluster IV also showed greater extending in the downswing. Finally, Cluster IV showed more lumbar lateral flexion towards the lead throughout. The results of this study have implications for scientific researchers as well as golf coaches, club-fitters and professionals. Commercially available launch monitors appear accurate enough for coaching applications, however caution is needed for scientific research when tracking a range of clubhead and ball parameters. Furthermore, changes in biomechanics when playing different trajectories has implications for future research and interpretation of published work, as well as for coaching theory. Future work following this thesis could utilise the optical tracking method to validate further commercial systems and for more detailed experimental investigation of clubhead-ball impacts. Furthermore, additional biomechanical investigation into a wider range of shot trajectories across more variables could be conducted, with a more in-depth understanding gained from principal components analysis and golfer clustering.
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Parijat, Prakriti. "Effects of Quadriceps Fatigue on the Outcomes of Slips and Falls." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/34825.
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Identifying potential risk factors that affect slip-induced falls is key to developing effective interventions for reduction of injuries caused by these accidents. Existing epidemiological evidence suggests that localized muscle fatigue might be considered as an intrinsic risk factor that causes lack of balance control leading to falls. The literature on the relationship between localized muscular fatigue of the lower extremity and the gait parameters affecting slip severity is scarce. The purpose of the present study was to examine how lower extremity fatigue (quadriceps) alters gait parameters and increases slip severity. Sixteen healthy young participants were recruited to walk across an unexpected slippery floor in two different sessions (Fatigue and No fatigue). Kinematic and kinetic data were collected using a three-dimensional video analysis system and force plates during both sessions. The gait parameters important in assessing slip severity were compared for the two different sessions to evaluate the effects of fatigue. A repeated measure one-way analysis of variance (ANOVA) and multivariate analysis was employed to predict statistical significance. The results indicated a substantial increase in the heel contact velocity (HCV), required coefficient of friction (RCOF), slip distance II (SDII), peak average knee joint moment during slip recovery (kneemompeak), fall frequency and, a decrease in the transitional acceleration of the whole body COM (TA) in the fatigue session further indicating higher slip severity due to fatigue. In addition, a strong positive correlation was observed between RCOF and HCV, HCV and SDII, and, SDII and kneemompeak. These findings provide new insights into the relationship between localized muscular fatigue and slip initiation/recovery process. The present study concluded that localized muscular fatigue affects the gait parameters and increases slip severity and hence can be considered as a potential risk factor for slip-induced falls.Master of Science
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McConnell, Evan Paul. "Assessing Symmetry in Landing Mechanics During Single-Leg and Bilateral Tasks in Healthy Recreational Athletes." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78348.
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INTRODUCTION: ACL-reconstructed (ACL-R) patients exhibit side-to-side asymmetries in movement and loading patterns after surgery, some of which are predictive of a secondary ACL injury. These asymmetries have not been fully assessed in healthy athletes. PURPOSE: To quantify side-to-side symmetry in secondary injury predictors in healthy athletes and compare these metrics to those measured in previous cohorts of ACL-R patients, as well as to assess differences in these metrics between two landing tasks and between sexes. METHODS: 60 healthy recreational athletes performed seven trials of a stop-jump task and seven trials of a single-leg hop for distance on each limb. The kinematics and kinetics of the first landing of the stop-jump and the landing of the single-leg hop were analyzed with a 10-camera motion analysis system (240Hz) and 2 embedded force plates (1920Hz). Limb symmetry indices (LSIs) were calculated for each variable and compared between subject groups, tasks, and sexes with Wilcoxon Signed Rank tests (p<0.05). RESULTS: Control subjects exhibited asymmetry in hop distance (p=0.006). ACL-R subjects displayed greater asymmetry in knee flexion variables, peak forces, and peak knee extension moments during the bilateral landing (p<0.001) and in hop distance (p<0.001). Control subjects showed greater asymmetry in knee flexion variables during the single-leg hop (p<0.001). Males and females showed similar symmetry in both tasks. CONCLUSIONS: Symmetry cannot be assumed in control subjects in all metrics. Asymmetries are more prevalent in ACL-R athletes than in healthy controls. Future work will continue to examine the usefulness of each metric in assessing ACL-R rehabilitation.Master of Science