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David Hawkins and Mark Smeulders

The purpose of this study was to determine if the characteristic Hill model, used to describe me force–velocity relationship for isolated tetanically stimulated muscle, could be modified and used to describe me torque–velocity behavior of me hip for maximally and submaximally stimulated hip extensor muscles. Fourteen subjects performed hip extension movements at effort levels of 100%, 70%, and 40% of a maximum isometric effort. A solenoid provided isometric resistance to hip extension. Once the desired effort level was achieved, as indicated by me isometric force, the solenoid released and me hip moved against an opposing elastic resistance equal to 75%, 50%, 25%, and 0% of the specified effort level. An electrogoniometer quantified hip angle. Hip velocity was determined by numerically differentiating the angle data. Torque-velocity-activation (or effort level) data were determined for each trial. Model parameters were determined to give me best fit to the data for each subject. Average parameter values were determined for each gender and for the entire group. The modified Hill-type model, T m = (T max · AK 1 · ω)/(K2 · ω + 1), accurately describes me relationship between joint torque (T m), maximum isometric joint torque (T max), joint velocity (ω), and muscle activation level (A) for subject-specific parameters (K 1 and K 2), but not for parameters averaged across genders or the entire group. Values for T max, K 1, and K 2 ranged from 90 to 385 Nm, 6.1 to 47.9 Nms, and 0.030 to 0.716 s, respectively.

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Natália Barros Beltrão, Camila Ximenes Santos, Valéria Mayaly Alves de Oliveira, André Luiz Torres Pirauá, David Behm, Ana Carolina Rodarti Pitangui, and Rodrigo Cappato de Araújo

significantly affect changes in range of motion (ROM), 2 , 3 passive torque response, 3 and muscle architecture, 4 there are few studies investigating stretch intensity effects within a chronic flexibility training program. There is conflict regarding stretching intensity in the literature, with some acute

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Karinna Sonálya Aires da Costa, Daniel Tezoni Borges, Liane de Brito Macedo, Caio Alano de Almeida Lins, and Jamilson Simões Brasileiro

limbs and for balance after a protocol using a frequency of 30 Hz and amplitude of 10 mm. They suggest that this improved performance immediately after the vibrating stimulus might be related to an increase in stretch reflex sensitivity. 13 Stewart et al 14 also found increased isometric peak torque

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Mary Hellen Morcelli, Dain Patrick LaRoche, Luciano Fernandes Crozara, Nise Ribeiro Marques, Camilla Zamfolini Hallal, Mauro Gonçalves, and Marcelo Tavella Navega

gait speed. 7 , 8 Poor lower limb strength has been associated with slow gait speed and the likelihood of falling, making it an important predictor of functional status in older adults. 9 – 12 The association exists because joint torques at the hip, knee, and ankle are summed in a coordinated fashion

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Mark Glaister, Colin Towey, Owen Jeffries, Daniel Muniz-Pumares, Paul Foley, and Gillian McInnes

with torque factors of 0.75 to 0.90 N·m·kg −1 . 3 – 9 With the exception of the findings of Woolf et al, 9 all have found no effect of caffeine on performance. Nevertheless, Anselme et al 10 and Glaister et al 11 observed a significant effect of caffeine on peak anaerobic power output as determined

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Noah X. Tocci, David R. Howell, Dai Sugimoto, Corey Dawkins, Amy Whited, and Donald Bae

High levels of torque placed on the upper body, and in particular the elbow, can result in greater injury risk as joint loading could exceed the yield points of dynamic and passive stabilizers of the elbow. 10 Kerut et al previously noted that signs of susceptibility to arm injury might begin

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Neal R. Glaviano and David M. Bazett-Jones

, clinicians and researchers often utilize hand-held dynamometers (HHDs). 14 – 16 HHDs provide reliable measures of hip force, yet there are additional considerations that clinicians must be aware of when assessing maximal capabilities of the hip muscles. One consideration for hip torque testing is patient

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Lasse Ishøi, Per Aagaard, Mathias F. Nielsen, Kasper B. Thornton, Kasper K. Krommes, Per Hölmich, and Kristian Thorborg

investigate the associations between peak isometric hamstring torque and hamstring rate of torque development (RTD) versus sprint performance in youth elite male football players. Methods Study Design This exploratory cross-sectional study was designed to investigate the association between hamstring muscle

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Lucas Ugliara, James J. Tufano, Martim Bottaro, and Amilton Vieira

The torque-generating capacity of plantar flexor muscles is of paramount importance for both performance and health. In terms of performance, evidence has shown that increasing running speed is more torque demanding for the plantar flexors than for the knee extensors for athletes ( Schache et

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Andrzej Kochanowicz, Bartłomiej Niespodziński, Jan Mieszkowski, Stanisław Sawczyn, Paweł Cięszczyk, and Kazimierz Kochanowicz

In addition to maximal strength, the ability to generate force or torque as quickly as possible (explosive muscle strength) is a muscle performance characteristic that is essential not only for sports performance, but also for daily living. A commonly used measure of the ability to generate maximum