Journal articles: 'Stretch tolerance'

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Law, Roberta Y. W., Lisa A. Harvey, Michael K. Nicholas, Lois Tonkin, Maria De Sousa, and Damien G. Finniss. "Stretch Exercises Increase Tolerance to Stretch in Patients With Chronic Musculoskeletal Pain: A Randomized Controlled Trial." Physical Therapy 89, no. 10 (October 1, 2009): 1016–26. http://dx.doi.org/10.2522/ptj.20090056.

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Background: Stretch is commonly prescribed as part of physical rehabilitation in pain management programs, yet little is known about its effectiveness.Objective: A randomized controlled trial was conducted to investigate the effects of a 3-week stretch program on muscle extensibility and stretch tolerance in patients with chronic musculoskeletal pain.Design: A within-subject design was used, with one leg of each participant randomly allocated to an experimental (stretch) condition and the other leg randomly allocated to a control (no-stretch) condition.Patients and Setting: Thirty adults with pain of musculoskeletal origin persisting for at least 3 months were recruited from patients enrolled in a multidisciplinary pain management program at a hospital in Sydney, Australia.Intervention: The hamstring muscles of the experimental leg were stretched daily for 1 minute over 3 weeks; the control leg was not stretched. This intervention was embedded within a pain management program and supervised by physical therapists.Measurements: Primary outcomes were muscle extensibility and stretch tolerance, which were reflected by passive hip flexion angles measured with standardized and nonstandardized torques, respectively. Initial measurements were taken before the first stretch on day 1, and final measurements were taken 1 to 2 days after the last stretch. A blinded assessor was used for testing.Results: Stretch did not increase muscle extensibility (mean between-group difference in hip flexion was 1°, 95% confidence interval=−2° to 4°), but it did improve stretch tolerance (mean between-group difference in hip flexion was 8°, 95% confidence interval=5° to 10°).Conclusion: Three weeks of stretch increases tolerance to the discomfort associated with stretch but does not change muscle extensibility in patients with chronic musculoskeletal pain.

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Mitchell, Ulrike H., J. William Myrer, J. Ty Hopkins, Iain Hunter, J. Brent Feland, and Sterling C. Hilton. "Acute Stretch Perception Alteration Contributes to the Success of the PNF “Contract-Relax” Stretch." Journal of Sport Rehabilitation 16, no. 2 (May 2007): 85–92. http://dx.doi.org/10.1123/jsr.16.2.85.

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Context:Some researchers have suggested that an alteration of stretch perception could be responsible for the success of the contract-relax (CR) stretch, a stretch technique derived from proprioceptive neuromuscular facilitation (PNF).Objective:This study was conducted to determine if the alteration of the stretch perception is a possible explanation for the range of motion (ROM) gains of the CR stretch.Participants:Eighteen subjects performed two stretches in randomized order: the slow stretch and the CR stretch.Main Outcome Measure:The stretch intensity was controlled. The stretch force was measured and compared between the slow stretch and CR stretch.Results:There was a significant difference between the stretch force that could be applied in the PNF stretch (126.0 N) and the slow stretch (108.4 N); P = 0.00086. The average stretch tolerance progressively increased with successive trials from 120.6 N in the first trial to 132.4 N in the fourth trial.Conclusion:The alteration of stretch perception plays a role in the success of the CR form of PNF stretching. At least four repetitions of the CR stretch are recommended to get the greatest ROM gain.

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Laessoe, U., and M. Voigt. "Modification of stretch tolerance in a stooping position." Scandinavian Journal of Medicine and Science in Sports 14, no. 4 (August 2004): 239–44. http://dx.doi.org/10.1111/j.1600-0838.2003.00332.x.

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Blazevich, A. J., D. Cannavan, C. M. Waugh, S. C. Miller, J. B. Thorlund, P. Aagaard, and A. D. Kay. "Range of motion, neuromechanical, and architectural adaptations to plantar flexor stretch training in humans." Journal of Applied Physiology 117, no. 5 (September 1, 2014): 452–62. http://dx.doi.org/10.1152/japplphysiol.00204.2014.

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The neuromuscular adaptations in response to muscle stretch training have not been clearly described. In the present study, changes in muscle (at fascicular and whole muscle levels) and tendon mechanics, muscle activity, and spinal motoneuron excitability were examined during standardized plantar flexor stretches after 3 wk of twice daily stretch training (4 × 30 s). No changes were observed in a nonexercising control group ( n = 9), however stretch training elicited a 19.9% increase in dorsiflexion range of motion (ROM) and a 28% increase in passive joint moment at end ROM ( n = 12). Only a trend toward a decrease in passive plantar flexor moment during stretch (−9.9%; P = 0.15) was observed, and no changes in electromyographic amplitudes during ROM or at end ROM were detected. Decreases in Hmax:Mmax(tibial nerve stimulation) were observed at plantar flexed (gastrocnemius medialis and soleus) and neutral (soleus only) joint angles, but not with the ankle dorsiflexed. Muscle and fascicle strain increased (12 vs. 23%) along with a decrease in muscle stiffness (−18%) during stretch to a constant target joint angle. Muscle length at end ROM increased (13%) without a change in fascicle length, fascicle rotation, tendon elongation, or tendon stiffness following training. A lack of change in maximum voluntary contraction moment and rate of force development at any joint angle was taken to indicate a lack of change in series compliance of the muscle-tendon unit. Thus, increases in end ROM were underpinned by increases in maximum tolerable passive joint moment (stretch tolerance) and both muscle and fascicle elongation rather than changes in volitional muscle activation or motoneuron pool excitability.

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Støve, Morten Pallisgaard, Rogerio Pessoto Hirata, and Thorvaldur Skuli Palsson. "The tolerance to stretch is linked with endogenous modulation of pain." Scandinavian Journal of Pain 21, no. 2 (January 11, 2021): 355–63. http://dx.doi.org/10.1515/sjpain-2020-0010.

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Abstract Objectives The effect of stretching on joint range of motion is well documented, and although sensory perception has significance for changes in the tolerance to stretch following stretching the underlining mechanisms responsible for these changes is insufficiently understood. The aim of this study was to examine the influence of endogenous pain inhibitory mechanisms on stretch tolerance and to investigate the relationship between range of motion and changes in pain sensitivity. Methods Nineteen healthy males participated in this randomized, repeated-measures crossover study, conducted on 2 separate days. Knee extension range of motion, passive resistive torque, and pressure pain thresholds were recorded before, after, and 10 min after each of four experimental conditions; (i) Exercise-induced hypoalgesia, (ii) two bouts of static stretching, (iii) resting, and (iv) a remote, painful stimulus induced by the cold pressor test. Results Exercise-induced hypoalgesia and cold pressor test caused an increase in range of motion (p<0.034) and pressure pain thresholds (p<0.027). Moderate correlations in pressure pain thresholds were found between exercise-induced hypoalgesia and static stretch (Rho>0.507, p=0.01) and exercise-induced hypoalgesia and the cold pressor test (Rho=0.562, p=0.01). A weak correlation in pressure pain thresholds and changes in range of motion were found following the cold pressor test (Rho=0.460, p=0.047). However, a potential carryover hypoalgesic effect may have affected the results of the static stretch. Conclusions These results suggest that stretch tolerance may be linked with endogenous modulation of pain. Present results suggest, that stretch tolerance may merely be a marker for pain sensitivity which may have clinical significance given that stretching is often prescribed in the rehabilitation of different musculoskeletal pain conditions where reduced endogenous pain inhibition is frequently seen.

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Magnusson, S. P., and B. Larsson. "ALTERED HAMSTRING FLEXIBILITY, STIFFNESS AND STRETCH TOLERANCE IN RUNNERS391." Medicine &amp Science in Sports &amp Exercise 29, Supplement (May 1997): 68. http://dx.doi.org/10.1097/00005768-199705001-00390.

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Billi, Daniela, Deborah J. Wright, Richard F. Helm, Todd Prickett, Malcolm Potts, and John H. Crowe. "Engineering Desiccation Tolerance inEscherichia coli." Applied and Environmental Microbiology 66, no. 4 (April 1, 2000): 1680–84. http://dx.doi.org/10.1128/aem.66.4.1680-1684.2000.

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ABSTRACT Recombinant sucrose-6-phosphate synthase (SpsA) was synthesized inEscherichia coli BL21DE3 by using the spsA gene of the cyanobacterium Synechocystis sp. strain PCC 6803. Transformants exhibited a 10,000-fold increase in survival compared to wild-type cells following either freeze-drying, air drying, or desiccation over phosphorus pentoxide. The phase transition temperatures and vibration frequencies (PO stretch) in phospholipids suggested that sucrose maintained membrane fluidity during cell dehydration.

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Støve, Morten Pallisgaard, Rogerio Pessoto Hirata, and Thorvaldur Skuli Palsson. "Muscle stretching – the potential role of endogenous pain inhibitory modulation on stretch tolerance." Scandinavian Journal of Pain 19, no. 2 (April 24, 2019): 415–22. http://dx.doi.org/10.1515/sjpain-2018-0334.

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Abstract Background and aims The effect of stretching on joint range of motion is well documented and is primarily related to changes in the tolerance to stretch, but the mechanisms underlying this change are still largely unknown. The aim of this study was to investigate the influence of a remote, painful stimulus on stretch tolerance. Methods Thirty-four healthy male subjects were recruited and randomly assigned to an experimental pain group (n=17) or a control group (n=17). Passive knee extension range of motion, the activity of hamstring muscles and passive resistive torque were measured with subjects in a seated position. Three consecutive measures were performed with a 5-min interval between. A static stretch protocol was utilized in both groups to examine the effect of stretching and differences in stretch tolerance between groups. Following this, the pain-group performed a cold pressor test which is known to engage the endogenous pain inhibitory system after which measurements were repeated. Results A significant increase in knee extension range of motion was found in the pain group compared with controls (ANCOVA: p<0.05). No difference was found in muscle activity or passive resistive torque between groups (ANCOVA p>0.091). Conclusions Passive knee extension range of motion following stretching increased when following a distant, painful stimulus, potentially engaging the endogenous pain inhibitory systems. Current findings indicate a link between increased tolerance to stretch and endogenous pain inhibition. Implications The current findings may have implications for clinical practice as they indicate that a distant painful stimulus can influence range of motion in healthy individuals. This implies that the modulation of pain has significance for the efficacy of stretching which is important knowledge when prescribing stretching as part of rehabilitation.

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Li, Jun Hong, and Hui Yu. "Numerical Simulation of Seamless Tube’s Stretch Reducing Process." Materials Science Forum 704-705 (December 2011): 155–59. http://dx.doi.org/10.4028/www.scientific.net/msf.704-705.155.

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The stretch reducing process is the last hot deformation process of the hot-rolled seamless steel tube’s production. Its role is to decrease the tube’s diameter under the large tension and expand the range of product specifications. But the stretch reducing process often results in wall thickness tolerance at the head and end of the tube. In order to solve the problem, a 3D elastic-plastic finite element analysis model was established to simulate the stretch reducing process of φ159 unit. Based on this, the tube’s wall thickness distribution was studied and the parameters of sharpen rolling process was put forward. Numerical simulation results indicate that with the parameters of sharpen rolling process, the length of wall thickness tolerance was shorten and the rate of finished products was proved.

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De Jaeger, Dominique, Venus Joumaa, and Walter Herzog. "Intermittent stretch training of rabbit plantarflexor muscles increases soleus mass and serial sarcomere number." Journal of Applied Physiology 118, no. 12 (June 15, 2015): 1467–73. http://dx.doi.org/10.1152/japplphysiol.00515.2014.

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In humans, enhanced joint range of motion is observed after static stretch training and results either from an increased stretch tolerance or from a change in the biomechanical properties of the muscle-tendon unit. We investigated the effects of an intermittent stretch training on muscle biomechanical and structural variables. The left plantarflexors muscles of seven anesthetized New Zealand (NZ) White rabbits were passively and statically stretched three times a week for 4 wk, while the corresponding right muscles were used as nonstretched contralateral controls. Before and after the stretching protocol, passive torque produced by the left plantarflexor muscles as a function of the ankle angle was measured. The left and right plantarflexor muscles were harvested from dead rabbits and used to quantify possible changes in muscle structure. Significant mass and serial sarcomere number increases were observed in the stretched soleus but not in the plantaris or medial gastrocnemius. This difference in adaptation between the plantarflexors is thought to be the result of their different fiber type composition and pennation angles. Neither titin isoform nor collagen amount was modified in the stretched compared with the control soleus muscle. Passive torque developed during ankle dorsiflexion was not modified after the stretch training on average, but was decreased in five of the seven experimental rabbits. Thus, an intermittent stretching program similar to those used in humans can produce a change in the muscle structure of NZ White rabbits, which was associated in some rabbits with a change in the biomechanical properties of the muscle-tendon unit.

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Blazevich, A. J., D. Cannavan, C. M. Waugh, F. Fath, S. C. Miller, and A. D. Kay. "Neuromuscular factors influencing the maximum stretch limit of the human plantar flexors." Journal of Applied Physiology 113, no. 9 (November 1, 2012): 1446–55. http://dx.doi.org/10.1152/japplphysiol.00882.2012.

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Maximum joint range of motion is an important parameter influencing functional performance and musculoskeletal injury risk. Nonetheless, a complete description of the muscle architectural and tendon changes that occur during stretch and the factors influencing maximum range of motion is lacking. We measured muscle-tendon elongation and fascicle lengthening and rotation sonographically during maximal plantar flexor stretches in 21 healthy men. Electromyogram (EMG) recordings were obtained synchronously with ultrasound and joint moment data, and H-reflex measurements were made with the ankle at neutral (0°) and dorsiflexed (50% maximal passive joint moment) positions; the maximum H amplitude (normalized to maximum M-wave amplitude; Mmax) and H-amplitude elicited at a stimulation intensity that evoked 10% Mmaxwere obtained. Maximal stretch was accomplished through significant muscle (14.9%; 30 mm) and tendon lengthening (8.4%; 22 mm). There were similar relative changes in fascicle length and angle, but planimetric modeling indicated that the contribution of fascicle rotation to muscle lengthening was small (<4 mm). Subjects with a greater range of motion showed less resistance to stretch and a greater passive joint moment at stretch termination than less flexible subjects (i.e., greater stretch tolerance). Also, greater fascicle rotation accompanied muscle elongation (9.7 vs. 5.9%) and there was a greater tendon length at stretch termination in more flexible subjects. Finally, a moderate correlation between the angle of EMG onset and maximum range of motion was obtained ( r = 0.60, P < 0.05), despite there being no difference in H-reflex magnitudes between the groups. Thus clear differences in the neuromuscular responses to stretch were observed between “flexible” and “inflexible” subjects.

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Folpp, Hollie, Simon Deall, Lisa A. Harvey, and Tom Gwinn. "Can apparent increases in muscle extensibility with regular stretch be explained by changes in tolerance to stretch?" Australian Journal of Physiotherapy 52, no. 1 (2006): 45–50. http://dx.doi.org/10.1016/s0004-9514(06)70061-7.

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Huang, Yan, Yang Huang, Wenjun Meng, Minshen Zhu, Hongtao Xue, Chun-Sing Lee, and Chunyi Zhi. "Enhanced Tolerance to Stretch-Induced Performance Degradation of Stretchable MnO2-Based Supercapacitors." ACS Applied Materials & Interfaces 7, no. 4 (January 20, 2015): 2569–74. http://dx.doi.org/10.1021/am507588p.

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Gläsner, Thorsten, Christina Sunderkötter, Armin Plath, Wolfram Volk, Hartmut Hoffmann, and Roland Golle. "Methods to Decrease Cut Edge Sensitivity of High Strength Steels." Key Engineering Materials 611-612 (May 2014): 1294–307. http://dx.doi.org/10.4028/www.scientific.net/kem.611-612.1294.

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The edge cracking sensitivity of AHSS and UHSS is quite challenging in the cold forming process. Expanding cut holes during flanging operations is rather common in automotive components. During these flanging operations the pierced hole is stretched that its diameter is increased. These flanging operations stretch material that has already been subjected to large amounts of plastic deformation, therefore forming problems may occur. An innovative cutting process decreases micro cracks in the cutting surface and facilitates the subsequent cold forming process. That cutting process consists of two stages, which produces close dimensional tolerance and smooth edges. As a result the hole expanding ratio was increased by nearly 100% when using thick high strength steels for suspension components

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Magnusson, S. P., E. B. Simonsen, P. Aagaard, J. Boesen, F. Johannsen, and M. Kjaer. "Determinants of musculoskeletal flexibility: viscoelastic properties, cross-sectional area, EMG and stretch tolerance." Scandinavian Journal of Medicine & Science in Sports 7, no. 4 (January 30, 2007): 195–202. http://dx.doi.org/10.1111/j.1600-0838.1997.tb00139.x.

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Parker Simpson, Rhianna, and John Cronin. "Reliability of a Unilateral Horizontal Leg Power Test to Assess Stretch Load Tolerance." Measurement in Physical Education and Exercise Science 10, no. 3 (September 2006): 169–78. http://dx.doi.org/10.1207/s15327841mpee1003_3.

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Smith, Douglas H., John A. Wolf, Theresa A. Lusardi, Virginia M. Y. Lee, and David F. Meaney. "High Tolerance and Delayed Elastic Response of Cultured Axons to Dynamic Stretch Injury." Journal of Neuroscience 19, no. 11 (June 1, 1999): 4263–69. http://dx.doi.org/10.1523/jneurosci.19-11-04263.1999.

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Ansari, Noureddin Nakhostin, Parisa Alaei, Soofia Naghdi, Zahra Fakhari, Shiva Komesh, and Jan Dommerholt. "Immediate Effects of Dry Needling as a Novel Strategy for Hamstring Flexibility: A Single-Blinded Clinical Pilot Study." Journal of Sport Rehabilitation 29, no. 2 (February 1, 2020): 156–61. http://dx.doi.org/10.1123/jsr.2018-0013.

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Context: There are numerous studies on the benefits of dry needling (DN) for pain relief. No studies exist examining the effects of DN on hamstring flexibility. Objective: To determine the immediate effects of DN on hamstring flexibility in healthy subjects with shortened hamstrings. Design: A single-blinded, pretest–posttest clinical pilot study. Setting: A university physiotherapy clinic. Subjects: A total of 15 healthy subjects (female = 11; age = 23.26 [4.3] y) with shortened hamstrings participated in this study. Intervention: Subjects received a single session of DN. Three locations on the hamstring muscle group were needled, each for 1 minute. Main Outcome Measures: The active knee extension test, muscle compliance, passive peak torque, and stretch tolerance were measured at baseline, immediately, and 15 minutes after DN. Results: There were statistically significant improvements in all outcome measures immediately after DN and at the 15-minute follow-up. The effect sizes for all outcome measures were large (Cohen’s d ≥ 0.8). No serious adverse events were observed with DN. Conclusions: This is the first study that demonstrates the beneficial effects of DN on hamstring flexibility, muscle compliance, and stretch tolerance without added stretching. The beneficial effects of DN should encourage clinicians to use DN as a novel strategy for increasing muscle flexibility.

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Gappmaier, E., B. Blake, D. Jeske, and D. Overly. "CHANGES IN MUSCLE LENGTH OR STRETCH TOLERANCE? EFFECTS OF A 12 MONTH HAMSTRING STRETCHING PROGRAM." Medicine & Science in Sports & Exercise 34, no. 5 (May 2002): S153. http://dx.doi.org/10.1097/00005768-200205001-00855.

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Hatano, Genki, Shigeyuki Suzuki, Shingo Matsuo, Satoshi Kataura, Kazuaki Yokoi, Taizan Fukaya, Mitsuhiro Fujiwara, Yuji Asai, and Masahiro Iwata. "Hamstring Stiffness Returns More Rapidly After Static Stretching Than Range of Motion, Stretch Tolerance, and Isometric Peak Torque." Journal of Sport Rehabilitation 28, no. 4 (May 1, 2019): 325–31. http://dx.doi.org/10.1123/jsr.2017-0203.

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Context: Hamstring injuries are common, and lack of hamstring flexibility may predispose to injury. Static stretching not only increases range of motion (ROM) but also results in reduced muscle strength after stretching. The effects of stretching on the hamstring muscles and the duration of these effects remain unclear. Objective: To determine the effects of static stretching on the hamstrings and the duration of these effects. Design: Randomized crossover study. Setting: University laboratory. Participants: A total of 24 healthy volunteers. Interventions: The torque–angle relationship (ROM, passive torque [PT] at the onset of pain, and passive stiffness) and isometric muscle force using an isokinetic dynamometer were measured. After a 60-minute rest, the ROM of the dynamometer was set at the maximum tolerable intensity; this position was maintained for 300 seconds, while static PT was measured continuously. The torque–angle relationship and isometric muscle force after rest periods of 10, 20, and 30 minutes were remeasured. Main Outcome Measures: Change in static PT during stretching and changes in ROM, PT at the onset of pain, passive stiffness, and isometric muscle force before stretching were compared with 10, 20, and 30 minutes after stretching. Results: Static PT decreased significantly during stretching. Passive stiffness decreased significantly 10 and 20 minutes after stretching, but there was no significant prestretching versus poststretching difference after 30 minutes. PT at the onset of pain and ROM increased significantly after stretching at all rest intervals, while isometric muscle force decreased significantly after all rest intervals. Conclusions: The effect of static stretching on passive stiffness of the hamstrings was not maintained as long as the changes in ROM, stretch tolerance, and isometric muscle force. Therefore, frequent stretching is necessary to improve the viscoelasticity of the muscle–tendon unit. Muscle force decreased for 30 minutes after stretching; this should be considered prior to activities requiring maximal muscle strength.

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R., Ganesh B., Veedika V. Marwah, and Vidhi S. Joshi. "Immediate effect of dynamic oscillatory stretching vs. neurodynamic sliding technique on stretch tolerance, popliteal angle range and hamstring flexibility in apparently healthy individuals with hamstring tightness: a pre-post clinical trail." International Journal of Research in Medical Sciences 7, no. 5 (April 26, 2019): 1862. http://dx.doi.org/10.18203/2320-6012.ijrms20191691.

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Background: The hamstrings being postural muscles are prone to tightness which leads to muscular imbalances and inefficiency of daily living activities. Hence, the present study aims to compare two competent techniques Dynamic Oscillatory Stretching (DOS)vs. neurodynamic sliding (NDS) technique.Methods: A Total of 60 subjects were recruited (31 males, 29 females). passive 90-90 knee extension test, modified v sit to reach test and NPRS scale were used to evaluate the range, flexibility and stretch tolerance in participants pre intervention and were allotted into Group A (DOS) and Groups B. The subjects were then re-assessed immediately post intervention.Results: The results were obtained using the independent and dependent t-tests. Post intervention results were suggestive of a significant within group result with a p=0.0001 under all the parameters. Subjects in Group a showed a greater increase in the ROM while, Group B showed a better result in flexibility and stretch tolerance.Conclusions: Both the techniques are efficient and can be incorporated in sports rehabilitation to prevent on site injury thereby improving athlete’s performance.

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Pietrzak, Max, and Niels B. J. Vollaard. "Effects of a Novel Neurodynamic Tension Technique on Muscle Extensibility and Stretch Tolerance: A Counterbalanced Crossover Study." Journal of Sport Rehabilitation 27, no. 1 (January 2018): 55–65. http://dx.doi.org/10.1123/jsr.2016-0171.

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Monkkonen, Eric H. "Homicide in Los Angeles, 1827–2002." Journal of Interdisciplinary History 36, no. 2 (October 2005): 167–83. http://dx.doi.org/10.1162/0022195054741235.

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An analysis of nearly two centuries of homicide data that stretch back to the Mexican period for the city and county of Los Angeles reveal a long history of violence in the region, one in which the homicide rate has consistently been higher than that of other major cities. Such factors as national culture, regional differences, demographics, economics, and political structure help to account for the persistence of this pattern. Does this traditional tolerance for violence and homicide in Los Angeles signify a local articulation of what is deemed normal, and could long-term efforts be devised to counter it?

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Nakamura, Masatoshi, Shigeru Sato, Ryosuke Kiyono, Kaoru Yahata, Riku Yoshida, Taizan Fukaya, Satoru Nishishita, and Andreas Konrad. "Association between the Range of Motion and Passive Property of the Gastrocnemius Muscle–Tendon Unit in Older Population." Healthcare 9, no. 3 (March 12, 2021): 314. http://dx.doi.org/10.3390/healthcare9030314.

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Range of motion has been widely known to decrease with age; however, factors associated with its decrease in the elderly population and especially its gender difference have been unclear. Therefore, this study aimed to investigate the factors associated with ankle dorsiflexion range of motion in the older population. Both male (n = 17, mean ± SD; 70.5 ± 4.2 years; 165.4 ± 5.3 cm; 63.8 ± 7.7 kg) and female (n = 25, 74.0 ± 4.0 years; 151.2 ± 4.9 cm; 50.1 ± 5.6 kg) community-dwelling older adults participated in this study. The ankle dorsiflexion and passive torque of both legs were measured using a dynamometer, and shear elastic modulus of the medial gastrocnemius muscle at 0° ankle angle was measured using ultrasonic shear wave elastography. In this study, we defined the passive torque at dorsiflexion range of motion (DF ROM) as the index of stretch tolerance, and shear elastic modulus as the index of passive muscle stiffness. The partial correlation coefficient adjusted by age, height, weight, and side (dominant or nondominant side) was used to analyze the relationship between DF ROM and passive torque at DF ROM or shear elastic modulus of MG in each male and female participant, respectively. Our results revealed that dorsiflexion range of motion was significantly associated with passive torque at dorsiflexion range of motion in both male (r = 0.455, p = 0.012) and female (r = 0.486, p < 0.01), but not with shear elastic modulus in both male (r = −0.123, p = 0.519) and female (r = 0.019, p = 0.898). Our results suggested that the ankle dorsiflexion range of motion could be related to the stretch tolerance, but not to passive muscle stiffness in community-dwelling elderly population regardless of gender.

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Geddes, Donna M., and Robert S. Cargill. "An in Vitro Model of Neural Trauma: Device Characterization and Calcium Response to Mechanical Stretch." Journal of Biomechanical Engineering 123, no. 3 (January 11, 2001): 247–55. http://dx.doi.org/10.1115/1.1374201.

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An in vitro model for neural trauma was characterized and validated. The model is based on a novel device that is capable of applying high strain rate, homogeneous, and equibiaxial deformation to neural cells in culture. The deformation waveform is fully arbitrary and controlled via closed-loop feedback. Intracellular calcium [Ca2+]i alterations were recorded in real time throughout the imposed strain with an epifluorescent microscopy system. Peak change in [Ca2+]i, recovery of [Ca2+]i, and percent responding NG108-15 cells were shown to be dependent on strain rate (1−1 to 10−1) and magnitude (0.1 to 0.3 Green’s Strain). These measures were also shown to depend significantly on the interaction between strain rate and magnitude. This model for neural trauma is a robust system that can be used to investigate the cellular tolerance and response to traumatic brain injury.

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Heymann, I. "Dynamic orthosis with low load prolonged stretch: Best tolerance and efficacity — application in cerebral palsy knee flexum contracture." Annals of Physical and Rehabilitation Medicine 55 (October 2012): e88. http://dx.doi.org/10.1016/j.rehab.2012.07.221.

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ElGhanam, Eiman, Mohamed Hassan, and Ahmed Osman. "Design of a High Power, LCC-Compensated, Dynamic, Wireless Electric Vehicle Charging System with Improved Misalignment Tolerance." Energies 14, no. 4 (February 8, 2021): 885. http://dx.doi.org/10.3390/en14040885.

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Dynamic wireless power transfer (DWPT) systems are becoming increasingly important for on-the-move electric vehicle (EV) charging solutions, to overcome range anxiety and compensate for the consumed energy while the EV is in motion. In this work, a DWPT EV charging system is proposed to be implemented on a straight road stretch such that it provides the moving EV with energy at a rate of 308 Wh/km. This rate is expected to compensate for the vehicle’s average energy consumption and allow for additional energy storage in the EV battery. The proposed charging system operates at an average power transfer efficiency that is higher than 90% and provides good lateral misalignment tolerance up to ±200 mm. Details of the proposed system’s design are presented in this paper, including EV specifications, inductive link and compensation network design and power electronic circuitry.

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Aishwarya Nair, Krishnaprasad K M, Gopala Krishna Alaparthi, Shyam Krishnan, and Santhosh Rai. "The effect of diaphragmatic stretch technique on diaphragmatic excursion in chronic obstructive pulmonary disease." International Journal of Research in Pharmaceutical Sciences 11, no. 3 (July 30, 2020): 4518–23. http://dx.doi.org/10.26452/ijrps.v11i3.2681.

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Chronic Obstructive Pulmonary Disease (COPD) is a preventable and treatable pulmonary disease that has extensive pulmonary and pathological adaptations. Few of these pathological changes are airway , persistent airflow limitation, finally leading to pulmonary hyperinflation. The diaphragm, which is the primary muscle of inspiration, is put through an excessive load due to the hyperinflation leading to its flattening, shortening and contraction at a mechanical disadvantage. These changes may lead to an increase in the work of breathing, a reduction in exercise tolerance and functional capacity, which makes it a potential target for therapeutic intervention. This single group and post-intervention study are aimed to find the effects of Diaphragmatic stretch technique on a diaphragmatic excursion in patients with mild or moderate COPD. The intervention was performed on the patients for two sets consisting of 10 breaths each with a 1-minute interval in between. The outcome measures recorded were diaphragmatic excursion and chest expansion which were taken before and immediately after the intervention. Results of the study showed a positive and statistically significant increase in the outcome measures following the intervention. The Diaphragmatic Stretch Technique has a considerable influence on patients with mild or moderate COPD without causing any or adverse effects.

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Buckner, Samuel L., Nathaniel D. M. Jenkins, Pablo B. Costa, Eric D. Ryan, Trent J. Herda, and Joel T. Cramer. "Comparing passive angle–torque curves recorded simultaneously with a load cell versus an isokinetic dynamometer during dorsiflexion stretch tolerance assessments." Medical Engineering & Physics 37, no. 5 (May 2015): 494–98. http://dx.doi.org/10.1016/j.medengphy.2015.02.010.

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Chen, Xiyuan, Loic Maxwell, Franklin Li, Amrita Kumar, Elliot Ransom, Tanay Topac, Sera Lee, Mohammad Faisal Haider, Sameh Dardona, and Fu-Kuo Chang. "Design and Integration of a Wireless Stretchable Multimodal Sensor Network in a Composite Wing." Sensors 20, no. 9 (April 29, 2020): 2528. http://dx.doi.org/10.3390/s20092528.

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This article presents the development of a stretchable sensor network with high signal-to-noise ratio and measurement accuracy for real-time distributed sensing and remote monitoring. The described sensor network was designed as an island-and-serpentine type network comprising a grid of sensor “islands” connected by interconnecting “serpentines.” A novel high-yield manufacturing process was developed to fabricate networks on recyclable 4-inch wafers at a low cost. The resulting stretched sensor network has 17 distributed and functionalized sensing nodes with low tolerance and high resolution. The sensor network includes Piezoelectric (PZT), Strain Gauge (SG), and Resistive Temperature Detector (RTD) sensors. The design and development of a flexible frame with signal conditioning, data acquisition, and wireless data transmission electronics for the stretchable sensor network are also presented. The primary purpose of the frame subsystem is to convert sensor signals into meaningful data, which are displayed in real-time for an end-user to view and analyze. The challenges and demonstrated successes in developing this new system are demonstrated, including (a) developing separate signal conditioning circuitry and components for all three sensor types (b) enabling simultaneous sampling for PZT sensors for impact detection and (c) configuration of firmware/software for correct system operation. The network was expanded with an in-house developed automated stretch machine to expand it to cover the desired area. The released and stretched network was laminated into an aerospace composite wing with edge-mount electronics for signal conditioning, processing, power, and wireless communication.

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Marshall, Paul W. M., Anthony Cashman, and Birinder S. Cheema. "A randomized controlled trial for the effect of passive stretching on measures of hamstring extensibility, passive stiffness, strength, and stretch tolerance." Journal of Science and Medicine in Sport 14, no. 6 (November 2011): 535–40. http://dx.doi.org/10.1016/j.jsams.2011.05.003.

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Oshiro, Masakatsu, Michael P. Hefferan, Osamu Kakinohana, Nadezda Lukacova, Kazuhiro Sugahara, Tony L. Yaksh, and Martin Marsala. "Suppression of stretch reflex activity after spinal or systemic treatment with AMPA receptor antagonist NGX424 in rats with developed baclofen tolerance." British Journal of Pharmacology 161, no. 5 (July 7, 2010): 976–85. http://dx.doi.org/10.1111/j.1476-5381.2010.00954.x.

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Prass, Friedrich, and Zamel. "Tolerance and Recovery of Ultralow-Loaded Platinum Anode Electrodes upon Carbon Monoxide and Hydrogen Sulfide Exposure." Molecules 24, no. 19 (September 27, 2019): 3514. http://dx.doi.org/10.3390/molecules24193514.

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The effects of carbon monoxide (CO) and hydrogen sulfide (H2S) in concentrations close to their respective limits in the Hydrogen Quality Standard ISO 14687-2:2012 on the performance of proton exchange membrane fuel cells (PEMFCs) with ultralow-loaded platinum anode catalyst layers (CLs) were investigated. The anodic loadings were 50, 25, and 15 µg/cm², which represent the current state-of-the-art, target, and stretch target, respectively, for future automotive PEMFCs. Additionally, the effect of shut-down and start-up (SD/SU) processes on recovery from sulfur poisoning was investigated. CO at an ISO concentration of 0.2 ppm caused severe voltage losses of ~40–50% for ultralow-loaded anode CLs. When H2S was in the fuel, these anode CLs exhibited both a nonlinear decrease in tolerance toward sulfur and an improved self-recovery during shut-down and start-up (SD/SU) processes. This observation was hypothesized to have resulted from the decrease in the ratio between CL thickness and geometric cell area, as interfacial effects of water in the pores increasingly impacted the performance of ultrathin CLs. The results indicate that during the next discussions on the Hydrogen Quality Standard, a reduction in the CO limit could be a reasonable alternative considering future PEMFC anodic loadings, while the H2S limit might not require modification.

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HATANO, Genki, Shigeyuki SUZUKI, Shingo MATSUO, Satoshi KATAURA, Masahiro IWATA, Yasuhiro BANNO, and Yuji ASAI. "312 Stiffness of the hamstrings is returned more rapidly than range of motion, stretch tolerance, and isometric peak torque after static stretching." Proceedings of the Symposium on sports and human dynamics 2012 (2012): 430–35. http://dx.doi.org/10.1299/jsmeshd.2012.430.

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May, Marcus, and Jens Jordan. "The osmopressor response to water drinking." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 300, no. 1 (January 2011): R40—R46. http://dx.doi.org/10.1152/ajpregu.00544.2010.

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Water drinking elicits profound pressor responses in patients with impaired baroreflex function and in sinoaortic-denervated mice. Healthy subjects show more subtle changes in heart rate and blood pressure with water drinking. The water-induced pressor response appears to be mediated through sympathetic nervous system activation at the spinal level. Indeed, water drinking raises resting energy expenditure in normal weight and obese subjects. The stimulus setting off the response is hypoosmolarity rather than water temperature or gastrointestinal stretch. Studies in mice suggest that this osmopressor response may involve transient receptor potential vanniloid 4 (Trpv4) receptors. However, the (nerve) cell population serving as peripheral osmosensors and the exact transduction mechanisms are still unknown. The osmopressor response can be exploited in the treatment of orthostatic and postprandial hypotension in patients with severe autonomic failure. Furthermore, the osmopressor response acutely improves orthostatic tolerance in healthy subjects and in patients with neurally mediated syncope. The phenomenon should be recognized as an important confounder in cardiovascular and metabolic studies.

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Stankiewicz, Anna. "Optimal and Robustly Optimal Consumption of Stretch Film Used for Wrapping Cylindrical Baled Silage." Agriculture 9, no. 12 (November 21, 2019): 248. http://dx.doi.org/10.3390/agriculture9120248.

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A conventional method for wrapping round bales of agricultural materials by wrappers with a rotating table or with rotating arms is considered. In contemporary agriculture, the demand for minimal consumption of the film used to wrap bales is very high, in order to apply this method with lower cost and less damage to the environment. A combined model-based problem of such a design, focusing on the width of stretch film and the overlap between adjacent film strips that minimizes film consumption, was mathematically formulated and solved. It was proven that the complete set of optimal film widths is defined by a simple algebraic equation described in terms of film, bale, and wrapping parameters. The optimal overlap ratios were found to be irreducible fractions in which the dividend is the divisor minus one; however, only the first three factions, 1 2 , 2 3 , and 3 4 , are practically significant. Next, the robustness to disturbances in the functioning of an actual bale wrapper, which leads to overlap ratio uncertainty, is examined. It was shown that, unfortunately, the optimal film widths applied together with the optimal overlaps do not provide any robustness to overlap variations. To overcome this inconvenience, the problems of a choice of the best commercially available film width guaranteeing minimal film consumption or maximal tolerance on the overlap uncertainty were formulated and solved. A new algorithm for a robust design of wrapping parameters was developed, motivated, and numerically verified to achieve a trade-off between satisfactory robustness and low film usage. For the resulting wrapping parameters, near-optimal film usage was achieved; the relative errors of the minimal film consumption approximation did not exceed 4%. It was proven that for the overlap, slightly more than 50%, i.e., 51% or 52%, provides both optimality and robustness of the overlap over disturbances, which are ensured regardless of the number of film layers. Moreover, it was found that for these overlaps and for the commercially available film widths selected according to the algorithm, the film consumption was more than twice as small than the film usage for exactly 50% overlap, if the actual overlap was smaller than pre-assumed. Similarly, an overlap of slightly more than the commonly used 67% will result in about 30% to 40% reduction in film usage in the presence of unfavorable disturbances, depending on the number of film layers and wrapping parameters.

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Akazawa, Naoki, Naomi Okawa, Masaki Kishi, Kiyoshi Nakatani, Katsuya Nishikawa, Daichi Tokumura, Yuji Matsui, and Hideki Moriyama. "Effects of long-term self-massage at the musculotendinous junction on hamstring extensibility, stiffness, stretch tolerance, and structural indices: A randomized controlled trial." Physical Therapy in Sport 21 (September 2016): 38–45. http://dx.doi.org/10.1016/j.ptsp.2016.01.003.

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Mishra, Shri Prakash. "Evaluation of the Physico-Chemical and Bacteriological Parameters of Gomti River in Sultanpur, Uttar Pradesh." SAMRIDDHI : A Journal of Physical Sciences, Engineering and Technology 11, no. 01 (July 25, 2019): 25–32. http://dx.doi.org/10.18090/samriddhi.v11i01.4.

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Gomti, the only river system of Sultanpur was studied for 16 prime physicochemical and 2 bacteriological parameters at six locations (viz., Kurwar, Golaghat, Dhobighat, Shmashan Ghat, Papar Ghat and Dhopap Ghat) of the district, for a period of one year for various seasons. The samples were collected in the month of January, May and August-2018 to study the seasonal variation in different parameters. For the Physico-chemical study, the analysed parameters are Temperature, Colour, Odour, Turbidity, Total Hardness, pH, Electrical Conductance (EC), Total Dissolved Solids, Alkalinity, Free Ammonia, Sulphates, Chlorides, Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD) and Free CO2. Total Coliforms MPN/100 ml and Faecal Coliforms MPN/100 ml is evaluated for Bacteriological eastimation. The water samples were analysed by emulating the Standard Methods for the Examination of Water and Waste Water, 21st Edition (APHA-2005). The river water quality is getting deteriorated day by day with an increase in the population and their over water consumption. Drinking, washing clothes and utensils, discharging of sewage waste, sand dredging, boating, fishing, open defecation and religious ritual activities along the stretch are generating serious threats to the flora and fauna of the river by changing physico-chemical and bacteriological quality of the river. The seasonal trends were discussed to comprehened anthropogenic interferences on the river stretch. Correlation analysis was also studied in between various physico-chemical and bacteriological parameters. By comparing with the tolerance limits of Bureau of Indian Standards (BIS: 10500-2012), it is concluded that the Gomti river in Sultanpur is very polluted. Considerable variation of many patameters from their standard values indicates that water of this river is not suitable for domestic uses. Continuous monitoring and treatment is required to keep the river living and suitable for aquatic biota as well as people depending on it.

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Mendonça, LB, EV Lopes, and L. Anjos. "On the possible extinction of bird species in the Upper Paraná River floodplain, Brazil." Brazilian Journal of Biology 69, no. 2 suppl (June 2009): 747–55. http://dx.doi.org/10.1590/s1519-69842009000300028.

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The Upper Paraná River floodplain (UPR) represents the last stretch of the Paraná River in Brazilian territory where a river-floodplain ecosystem still exists. However, the region had been subjected to intense deforestation in previous decades, and more than half of the original floodplain has been lost due to the construction of the Porto Primavera dam, which may have resulted in the local extinction of species. In the present study, we compared the list of bird species recorded before the construction of Porto Primavera dam (1926-1996) to that gotten afterwards (1999-2007) under the Long-Term Ecological Research program (LTER-site 6). We aim to investigate biogeographical and ecological traits of species potentially lost in the UPR. Endemism, proximity to the edge of species' geographic range, low tolerance to human-altered habitats and habitat specificity were associated to the potential extinction of birds in the UPR. The region represents an important opportunity for conservation, and should be target of conservation efforts to avoid further loss of species and ecological processes.

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Fukaya, Taizan, Masatoshi Nakamura, Shigeru Sato, Ryosuke Kiyono, Kaoru Yahata, Kazuki Inaba, Satoru Nishishita, and Hideaki Onishi. "The Relationship between Stretching Intensity and Changes in Passive Properties of Gastrocnemius Muscle-Tendon Unit after Static Stretching." Sports 8, no. 11 (October 23, 2020): 140. http://dx.doi.org/10.3390/sports8110140.

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This study aimed to investigate the relationship between relative or absolute intensity and changes in range of motion and passive stiffness after static stretching. A total of 65 healthy young adults voluntarily participated in this study and performed static stretching of the plantar flexor-muscle for 120 s. Dorsiflexion range of motion and passive torque during passive dorsiflexion before and after stretching were assessed. We measured the passive torque at a given angle when the minimum angle was recorded before and after stretching. The angle during stretching was defined as the absolute intensity. Dorsiflexion range of motion before stretching was defined as 100%, and the ratio (%) of the angle during stretching was defined as the relative intensity. A significant correlation was found between absolute intensity and change in passive torque at a given angle (r = −0.342), but relative intensity and range of motion (r = 0.444) and passive torque at dorsiflexion range of motion (r = 0.259). A higher absolute intensity of stretching might be effective in changing the passive properties of the muscle-tendon unit. In contrast, a higher relative intensity might be effective in changing the range of motion, which could be contributed by stretch tolerance.

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Pakulski, Jan. "Legitimacy and Mass Compliance: Reflections on Max Weber and Soviet-Type Societies." British Journal of Political Science 16, no. 1 (January 1986): 35–56. http://dx.doi.org/10.1017/s0007123400003793.

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It is worthwhile debating the meaning of concepts only when they start to hinder the process of inquiry. This seems to be the case with Max Weber's concepts of legitimacy and legitimate authority. They are becoming increasingly popular among students of Soviet-type societies despite the numerous problems posed by their application in a socio-political context that is so different from the one Weber had in mind. This increased popularity results in a ‘conceptual stretch’. More importantly, it increases the danger of a serious misinterpretation of socio-political processes in Soviet-type societies because, as will be argued in this article, the concept of legitimacy is not appropriate for the analysis of mass compliance in such societies. Instead, the persistence of (relatively) stable social and political order in these societies, as well as the occurrences of mass dissent, may be better accounted for in terms of ‘conditional tolerance’. In order to demonstrate the utility of this concept, and to show the problematic nature of accounts in terms of legitimacy and legitimate authority, it is necessary to start with a brief reprise of Weber's conceptual scheme.

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Konrad, Andreas, and Markus Tilp. "Effects of ballistic stretching training on the properties of human muscle and tendon structures." Journal of Applied Physiology 117, no. 1 (July 1, 2014): 29–35. http://dx.doi.org/10.1152/japplphysiol.00195.2014.

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The purpose of this study was to investigate the influence of a 6-wk ballistic stretching training program on various parameters of the human gastrocnemius medialis muscle and the Achilles tendon. It is known that ballistic stretching is an appropriate means of increasing the range of motion (RoM), but information in the literature about the mechanical adaptation of the muscle-tendon unit (MTU) is scarce. Therefore, in this study, a total of 48 volunteers were randomly assigned into ballistic stretching and control groups. Before and following the stretching intervention, we determined the maximum dorsiflexion RoM with the corresponding fascicle length and pennation angle. Passive resistive torque (PRT) and maximum voluntary contraction (MVC) were measured with a dynamometer. Muscle-tendon junction (MTJ) displacement allowed us to determine the length changes in tendon and muscle, and hence to calculate stiffness. Mean RoM increased significantly from 33.8 ± 6.3° to 37.8 ± 7.2° only in the intervention group, but other functional (PRT, MVC) and structural (fascicle length, pennation angle, muscle stiffness, tendon stiffness) parameters were unaltered. Thus the increased RoM could not be explained by structural changes in the MTU and was likely due to increased stretch tolerance.

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Hayes, Bradley T., Rod A. Harter, Jeffrey J. Widrick, Daniel P. Williams, Mark A. Hoffman, and Charlie A. Hicks-Little. "Lack of Neuromuscular Origins of Adaptation After a Long-Term Stretching Program." Journal of Sport Rehabilitation 21, no. 2 (May 2012): 99–106. http://dx.doi.org/10.1123/jsr.21.2.99.

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Context:Static stretching is commonly used during the treatment and rehabilitation of orthopedic injuries to increase joint range of motion (ROM) and muscle flexibility. Understanding the physiological adaptations that occur in the neuromuscular system as a result of long-term stretching may provide insight into the mechanisms responsible for changes in flexibility.Objective:To examine possible neurological origins and adaptations in the Ia-reflex pathway that allow for increases in flexibility in ankle ROM, by evaluating the reduction in the synaptic transmission of Ia afferents to the motoneuron pool.Design:Repeated-measures, case-controlled study.Setting:Sports medicine research laboratory.Participants:40 healthy volunteers with no history of cognitive impairment, neurological impairment, or lower extremity surgery or injury within the previous 12 mo.Intervention:Presynaptic and postsynaptic mechanisms were evaluated with a chronic stretching protocol. Twenty subjects stretched 5 times a wk for 6 wk. All subjects were measured at baseline, 3 wk, and 6 wk.Main Outcome Measures:Ankle-dorsiflexion ROM, Hmax:Mmax, presynaptic inhibition, and disynaptic reciprocal inhibition.Results:Only ROM had a significant interaction between group and time, whereas the other dependent variables did not show significant differences. The experimental group had significantly improved ROM from baseline to 3 wk (mean 6.2 ± 0.9, P < .001), 3 wk to 6 wk (mean 5.0 ± 0.8, P < .001), and baseline to 6 wk (mean 11.2 ±0.9, P < .001).Conclusions:Ankle dorsiflexion increased by 42.25% after 6 wk of static stretching, but no significant neurological changes resulted at any point of the study, contrasting current literature. Significant neuromuscular origins of adaptation do not exist in the Ia-reflex-pathway components after a long-term stretching program as currently understood. Thus, any increases in flexibility are the result of other factors, potentially mechanical changes or stretch tolerance.

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Kuraeva, T. L., O. V. Remizov, B. A. Arkhipov, and I. I. Dedov. "Telangiectasia, ataxia, hypermobility syndrome, hypertrophic cardiomyopathy and diabetes - a new syndrome?" Problems of Endocrinology 42, no. 2 (April 15, 1996): 32–34. http://dx.doi.org/10.14341/probl12027.

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The proportion of people with genetic syndromes accompanied by diabetes mellitus or impaired tolerance to carbohydrates is less than 1% among all patients with diabetes mellitus. Currently, more than 70 such syndromes are described, in the clinical manifestation of which impaired tolerance to carbohydrates or diabetes mellitus is important. Examples include ataxia - telangiectasia, myotonic dystrophy, generalized or partial lipodystrophy. In the available literature, we have not seen any observations of the combination of diabetes mellitus with telangiectasias, ataxia, hypermobility of the joints, hyper-stretch of the skin, hypertrophic cardiomyopathy. We give an observation. Patient A., 15 years old, was admitted to the children's department of the Institute of Diabetes of the Endocrinology Research Centre of the Russian Academy of Medical Sciences with complaints of sharp weakness in the legs, inability to move independently, bleeding gums, nosebleeds, thirst, polyuria. Mother 39 years old, father 43 years old, sister 12 years old, all are healthy. A patient from the 3rd pregnancy, which proceeded with the threat of interruption throughout pregnancy. Two previous pregnancies in the patient's mother ended in miscarriages. Childbirth at the 8th month in the buttock presentation, with placental abruption. Body weight at birth 1800 g, body length 44 cm. The patient was born in asphyxia, with hemorrhages in the skin of the face. At the age of 2 years, 3 months after ARVI, the child developed shortness of breath, liver enlargement up to 6 cm from under the edge of the costal arch along the midclavicular line, and an increase in systolic blood pressure to 130 mm Hg. Art. At 3 years 4 months old, the diagnosis was established: idiopathic hypertrophic subaortic stenosis. From this age, the patient was periodically disturbed by severe abdominal pain, accompanied by nausea and vomiting, which were regarded as an exacerbation of chronic pancreatitis. The last attack at 15 years (urine amylase within normal limits). At 6 years of age, due to frequent nosebleeds observed from the age of 5, as well as telangiectasia of the skin vessels, he was diagnosed with OslerWeberRendu syndrome disease. In connection with the persisting hepatomegaly, a glucose tolerance test was performed at the age of 15 to exclude glycogenosis. A violation of tolerance to carbohydrates was revealed. After 1 month, symptoms of diabetes appeared. After another 1 month in a precomatous state, the patient was hospitalized in the regional children's hospital at the place of residence. At discharge, the daily dose of insulin was 44 units. 3 months after the manifestation of diabetes mellitus appeared weakness in the legs, which progressed rapidly. After 5 months, the patient was hospitalized at the Endocrinology Research Centre of RAMS.

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Morton, Robert W., Sara Y. Oikawa, Stuart M. Phillips, Michaela C. Devries, and Cameron J. Mitchell. "Self–Myofascial Release: No Improvement of Functional Outcomes in “Tight” Hamstrings." International Journal of Sports Physiology and Performance 11, no. 5 (July 2016): 658–63. http://dx.doi.org/10.1123/ijspp.2015-0399.

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Purpose:Self–myofascial release (SMR) is a common exercise and therapeutic modality shown to induce acute improvements in joint range of motion (ROM) and recovery; however, no long-term studies have been conducted. Static stretching (SS) is the most common method used to increase joint ROM and decrease muscle stiffness. It was hypothesized that SMR paired with SS (SMR+SS) compared with SS alone over a 4-wk intervention would yield greater improvement in knee-extension ROM and hamstring stiffness.Methods:19 men (22 ± 3 y) with bilateral reduced hamstring ROM had each of their legs randomly assigned to either an SMR+SS or an SS-only group. The intervention consisted of 4 repetitions of SS each for 45 s or the identical amount of SS preceded by 4 repetitions of SMR each for 60 s and was performed on the respective leg twice daily for 4 wk. Passive ROM, hamstring stiffness, rate of torque development (RTD), and maximum voluntary contraction (MVC) were assessed pre- and postintervention.Results:Passive ROM (P < .001), RTD, and MVC (P < .05) all increased after the intervention. Hamstring stiffness toward end-ROM was reduced postintervention (P = .02). There were no differences between the intervention groups for any variable.Conclusion:The addition of SMR to SS did not enhance the efficacy of SS alone. SS increases joint ROM through a combination of decreased muscle stiffness and increased stretch tolerance.

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Siddiqui, Mohammad Tahir, Aftab Hossain Mondal, Firdoos Ahmad Gogry, Fohad Mabood Husain, Ali Alsalme, and Qazi Mohd Rizwanul Haq. "Plasmid-Mediated Ampicillin, Quinolone, and Heavy Metal Co-Resistance among ESBL-Producing Isolates from the Yamuna River, New Delhi, India." Antibiotics 9, no. 11 (November 19, 2020): 826. http://dx.doi.org/10.3390/antibiotics9110826.

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Antibiotic resistance is one of the major current global health crises. Because of increasing contamination with antimicrobials, pesticides, and heavy metals, the aquatic environment has become a hotspot for emergence, maintenance, and dissemination of antibiotic and heavy metal resistance genes among bacteria. The aim of the present study was to determine the co-resistance to quinolones, ampicillin, and heavy metals among the bacterial isolates harboring extended-spectrum β-lactamases (ESBLs) genes. Among 73 bacterial strains isolated from a highly polluted stretch of the Yamuna River in Delhi, those carrying blaCTX-M, blaTEM, or blaSHV genes were analyzed to detect the genetic determinants of resistance to quinolones, ampicillin, mercury, and arsenic. The plasmid-mediated quinolone resistance (PMQR) gene qnrS was found in 22 isolates; however, the qnrA, B, C, and qnrD genes could not be detected in any of the bacteria. Two variants of CMY, blaCMY-2 and blaCMY-42, were identified among eight and seven strains, respectively. Furthermore, merB, merP, merT, and arsC genes were detected in 40, 40, 44, and 24 bacterial strains, respectively. Co-transfer of different resistance genes was also investigated in a transconjugation experiment. Successful transconjugants had antibiotic and heavy metal resistance genes with similar tolerance toward antibiotics and heavy metals as did their donors. This study indicates that the aquatic environment is a major reservoir of bacteria harboring resistance genes to antibiotics and heavy metals and emphasizes the need to study the genetic basis of resistant microorganisms and their public health implications.

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Stabley, John N., James M. Dominguez, Catherine E. Dominguez, Fredy R. Mora Solis, Joslyn Ahlgren, Bradley J. Behnke, Judy M. Muller-Delp, and Michael D. Delp. "Spaceflight reduces vasoconstrictor responsiveness of skeletal muscle resistance arteries in mice." Journal of Applied Physiology 113, no. 9 (November 1, 2012): 1439–45. http://dx.doi.org/10.1152/japplphysiol.00772.2012.

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Cardiovascular adaptations to microgravity undermine the physiological capacity to respond to orthostatic challenges upon return to terrestrial gravity. The purpose of the present study was to investigate the influence of spaceflight on vasoconstrictor and myogenic contractile properties of mouse gastrocnemius muscle resistance arteries. We hypothesized that vasoconstrictor responses acting through adrenergic receptors [norepinephrine (NE)], voltage-gated Ca2+ channels (KCl), and stretch-activated (myogenic) mechanisms would be diminished following spaceflight. Feed arteries were isolated from gastrocnemius muscles, cannulated on glass micropipettes, and physiologically pressurized for in vitro experimentation. Vasoconstrictor responses to intraluminal pressure changes (0–140 cmH2O), KCl (10–100 mM), and NE (10−9-10−4 M) were measured in spaceflown (SF; n = 11) and ground control (GC; n = 11) female C57BL/6 mice. Spaceflight reduced vasoconstrictor responses to KCl and NE; myogenic vasoconstriction was unaffected. The diminished vasoconstrictor responses were associated with lower ryanodine receptor-2 (RyR-2) and ryanodine receptor-3 (RyR-3) mRNA expression, with no difference in sarcoplasmic/endoplasmic Ca2+ ATPase 2 mRNA expression. Vessel wall thickness and maximal intraluminal diameter were unaffected by spaceflight. The data indicate a deficit in intracellular calcium release via RyR-2 and RyR-3 in smooth muscle cells as the mechanism of reduced contractile activity in skeletal muscle after spaceflight. Furthermore, the results suggest that impaired end-organ vasoconstrictor responsiveness of skeletal muscle resistance arteries contributes to lower peripheral vascular resistance and less tolerance of orthostatic stress in humans after spaceflight.

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Shi, Riyi, and Jim Whitebone. "Conduction Deficits and Membrane Disruption of Spinal Cord Axons as a Function of Magnitude and Rate of Strain." Journal of Neurophysiology 95, no. 6 (June 2006): 3384–90. http://dx.doi.org/10.1152/jn.00350.2005.

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White matter strips extracted from adult guinea pig spinal cords were subjected to tensile strain (stretch) injury ex vivo. Strain was carried out at three magnitudes (25, 50, and 100%) and two strain rate regimens: slow (0.006–0.008 s−1) and fast (355–519 s−1). The cord samples were monitored physiologically using a double sucrose-gap technique and anatomically using a horseradish peroxidase assay. It seems that a higher magnitude of strain inflicted significantly more functional and structural damage within each strain rate group. Likewise, a higher strain rate inflicted more damage when the strain magnitude was maintained. It is evident that axons have remarkable tolerance to strain injury at a slow strain rate. Even a 100% strain at the slow rate only eliminated two-thirds of the compound action potential amplitude and resulted in almost no membrane damage when examined 30 min after strain. It is also clear that the spontaneous recovery is evident yet not complete compared with preinjury levels at the fast strain rate. To examine the factors that might influence the vulnerability of axons to strain, we have shown that the axonal diameters did not play a significant role in dictating the susceptibility of axons to strain. Rather, it is speculated that the location of axons might be a more important factor in this regard. The knowledge gained from this study is likely to be informative in elucidating the spinal cord biomechanical response to strain and strain rate.

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Marshall, Paul W. M., Ric Lovell, and Jason C. Siegler. "Changes in Passive Tension of the Hamstring Muscles During a Simulated Soccer Match." International Journal of Sports Physiology and Performance 11, no. 5 (July 2016): 594–601. http://dx.doi.org/10.1123/ijspp.2015-0009.

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Purpose:Passive muscle tension is increased after damaging eccentric exercise. Hamstring-strain injury is associated with damaging eccentric muscle actions, but no research has examined changes in hamstring passive muscle tension throughout a simulated sport activity. The authors measured hamstring passive tension throughout a 90-min simulated soccer match (SAFT90), including the warm-up period and every 15 min throughout the 90-min simulation.Methods:Passive hamstring tension of 15 amateur male soccer players was measured using the instrumented straight-leg-raise test. Absolute torque (Nm) and slope (Nm/°) of the recorded torque-angular position curve were used for data analysis, in addition to total leg range of motion (ROM). Players performed a 15-min prematch warm-up, then performed the SAFT90 including a 15-min halftime rest period.Results:Reductions in passive stiffness of 20–50° of passive hip flexion of 22.1−29.2% (P < .05) were observed after the warm-up period. During the SAFT90, passive tension increased in the latter 20% of the range of motion of 10.1−10.9% (P < .05) concomitant to a 4.5% increase in total hamstring ROM (P = .0009).Conclusions:The findings of this study imply that hamstring passive tension is reduced after an active warm-up that includes dynamic stretching but does not increase in a pattern suggestive of eccentric induced muscle damage during soccer-specific intermittent exercise. Hamstring ROM and passive tension increases are best explained by improved stretch tolerance.

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Nakamura, Masatoshi, Tome Ikezoe, Hiroki Umegaki, Takuya Kobayashi, Satoru Nishishita, and Noriaki Ichihashi. "Changes in Passive Properties of the Gastrocnemius Muscle–Tendon Unit During a 4-Week Routine Static-Stretching Program." Journal of Sport Rehabilitation 26, no. 4 (July 2017): 263–68. http://dx.doi.org/10.1123/jsr.2015-0198.

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Context:Static stretching (SS) is commonly performed in a warm-up routine to increase joint range of motion (ROM) and to decrease muscle stiffness. However, the time course of changes in ankle-dorsiflexion (DF) ROM and muscle stiffness during a routine SS program is unclear.Objective:To investigate changes in ankle-DF ROM, passive torque at DF ROM, and muscle stiffness during a routine SS program performed 3 times weekly for 4 wk.Design:A quasi-randomized controlled-trial design.Participants:The subjects comprised 24 male volunteers (age 23.8 ± 2.3 y, height 172.0 ± 4.3 cm, body mass 63.1 ± 4.5 kg) randomly assigned to either a group performing a 4-wk stretching program (SS group) or a control group.Main Outcome Measures:DF ROM, passive torque, and muscle stiffness were measured during passive ankle dorsiflexion in both groups using a dynamometer and ultrasonography once weekly during the 4-wk intervention period.Results:In the SS group, DF ROM and passive torque at DF ROM significantly increased after 2, 3, and 4 wk compared with the initial measurements. Muscle stiffness also decreased significantly after 3 and 4 wk in the SS group. However, there were no significant changes in the control group.Conclusions:Based on these results, the SS program effectively increased DF ROM and decreased muscle stiffness. Furthermore, an SS program of more than 2 wk duration effectively increased DF ROM and changed the stretch tolerance, and an SS program more than 3 wk in duration effectively decreased muscle stiffness.

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Journal articles on the topic 'Stretch tolerance'

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