Evaluation Of The Isokinetic Strength Of Hamstrings / Quadriceps Ratio In Elite Weight Lifters

Introduction
Several studies have suggested the hamstrings and quadriceps (H/Q) ratio for the purposes of injury prevention and
rehabilitation. However, only a few studies have considered the specific sport requirement for the muscle contraction
speed. The purpose of this study was to evaluate the isokinetic strength of hamstrings and quadriceps (H/Q) ratio of
elite weight lifters (WLs) and to investigate the difference of H/Q ratio in the dominant and nondominant side of the
athletes.

Methods
Twenty national level WLs（13 males, 7 females） from NCPES volunteered as subjects. Two speeds of 60°/s and
300°/s was used to investigate subjects’ isokinotic strength by Biodex System III dynamometer. Subjects performed 5
maximal voluntary knee extensions and flexions at both speeds, to test the peak torque of their strength.

Results
The results showed that the ratios were about 0.44-0.46 for women, and 0.51-0.53 for men at low and high
speed（Table 1）. There was no significant difference between the dominant and nondominant regards of gender（α
＜.05）. Subjects consent form was obtained before the administrative from of the test.

Discussion / Conclusions
The results of this study suggested that weight lifters due to the specific movements required during squat down and up,
making quadriceps strength stronger. Their H/Q ratios trended to have a specifical values. There was no significant of
dominant and nondominant of athletes, thus, the concentric strength which was decided no matter what side could be
accepted.

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