Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed July 9, 2007). PDF text: vii, 77 p. UMI publication number: AAT 3247183. Includes bibliographical references. Also available in microfilm and microfiche formats.

Fourteen college softball players were recruited to participate in this study to determine if a strength imbalance between the lower extremities, how significant this difference this may be and of any correlations existed among all the functional tests. Subjects took part in isokinetic flexion and extension at 60 and 240 deg/sec, parallel squats, 2-legged vertical jump, single leg vertical jump, and a five-hop test. Peak and average torque was recorded for isokinetic testing and revealed significant differences between the dominant and non-dominant limbs (13.00%- 16.00%). Peak and average force was analyzed for squats and all vertical jumps. Significance was found among all activities between dominant and non-dominant legs, other than average force for single leg vertical jump. A significant difference was also exhibited for the five-hop test between the lower extremities. Significant correlations were also found at the 0.05 and 0.01 levels amongst the various functional tests. Overall findings revealed a significant strength imbalance between the dominant and non-dominant limbs. Further research needs to be conducted in determining how detrimental these differences could be in daily performance for athletes. / School of Physical Education

Thesis (MAppSc in Physiotherapy)--University of South Australia, 1996

Thesis (M.S.)--University of Texas at El Paso, 2008. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

The purpose of this study was to determine if isokinetic testing could be used as an effective means of assessing a players potential to play a certain position. The subjects were twenty four male division IA college football players. The Cybex 340 isokinetic testing device, twenty and forty yard dash, and standing broad jump were used to collect data. An analysis of variance test with repeated measures was used for the statistical analysis (ANOVA). Based on the findings of this study, no significant difference was found between offensive and defensive lineman, through isokinetic testing. However, a significant difference was found between the groups in the twenty and forty yard dash, and in the standing broad jump. Significant differences in these areas may have been attributed to a significant difference in body weight between the two groups tested. / School of Physical Education

Many devices are available on the market for the evaluation and rehabilitation of patients suffering from muscular disorders. Most of them are small, low-cost, passive devices based on the use of springs and resistive elements and exhibit very limited (or even not any) evaluation capabilities; extended muscular force evaluation is only possible on stationary, expensive, multi-purpose devices, available only in hospitals, which offer many exercise modes (e.g. isokinetic mode) that are not available on other devices. The objective of this thesis is to make the functionalities currently only implemented on bulky multi-purpose devices available at a lower cost and in a portable fashion, enabling their use by a large number of independent practitioners and patients, even at home (tele-medecine applications). In order to achieve this goal, a portable rehabilitation device, using a magneto-rheological fluid brake as actuator, has been designed. This particular technology was selected for its high level of compactness, simple mechanical design, high controllability, smooth and safe operation. The first part of this thesis is devoted to the design of MR-fluid brakes and their experimental validation. The second part is dedicated to the design of the rehabilitation device and the comparison of its performances with a commercial multi-purpose device (CYBEX).

The main purpose of this study was to investigate the relationship between human growth hormone (hGH) and two separate components of resistance exercise. Eight non-weight-trained subjects (23.33 ± 0.3 yrs) performed three force production trials (FPT), at different concentric workloads, and an 120% eccentric exercise trial (EET) on the Cybex 6000. Blood samples (3 mls) were taken pre- and post-exercise and analyzed for lactate, creatine kinase (CK) and hGH. Electromyographic (EMG) activity of the quadriceps muscle was recorded during each trial. The mean peak torque produced during the FPTs increased as work intensity increased but was the highest in the EET. The data for total work showed a proportional relationship with the intensity of the three concentric work loads but not the 120% EET. EMG activity of vastus medialis (VM) and rectus femoris (RF) measured during EET was 26% less than RF of 50% and 15% less than VL of 70% in FPT, respectively. The highest hormonal response occurred following the 120% EET. The hormonal response following the FPTs was highest in the 90% FPT with the two lower work intensity trials (50 and 70%) showing no clear hormonal response. Although the hGH response was the highest in the 120% EET, the post-exercise lactic acid levels in EET were 24% less than that of the 90% FPT. Creatine kinase (CK) activity was significantly elevated 36 hours after the last bout of EET which suggests that the eccentric exercise resulted in muscle damage. The results from concentric trials showed that muscle force generation, EMG, and lactic acid of the three different concentric trials were well correlated to the pattern of hGH secretion. However, only peak torque was consistent with the hGH response of the EET. The highest peak torque and hGH levels were achieved with eccentric exercise. The highest levels of fatigue, as a result of the combination of longer exercise time and overloading of the muscle during EET, may explain the higher hGH output. The muscle damage caused by the eccentric trial was enough to induce delayed onset of muscle soreness and may be the stimulus for the higher hGH output. The hGH response may facilitate repair of the muscular damage induced by eccentric exercise by promoting protein synthesis. / School of Physical Education

Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 55-58). / ix, 58 leaves, bound ill. 29 cm

Thesis (Ph.D.)--Baylor University, 2008. / Includes bibliographical references (p. 131-148).

Thesis (M.S.E.)--Northern Illinois University, 2002. / Includes bibliographical references (leaves [45]-47).