Effects of short-term isokinetic training on standing long-jump performance in untrained men

The purpose of this study was to examine the effects of a 6-week isokinetic training program on quadriceps and hamstrings peak torque (PT) and standing long-jump (SLJ) performance. Twelve untrained men (age 31.4 +/- 4.2 years, mean +/- SD) were tested at a velocity of 1.75 rad.s(-1) (100 degrees.s(-1)), before and after a 6-week control period and on completion of a 6-week training program. Training consisted of 3 sets of 10 repetitions, 3 days per week, for 6 weeks. Repeated-measures analysis-of-variance analyses revealed that quadriceps PT increased, on average, by 10.5% as a result of training (p < 0.01). No significant changes in hamstrings PT (p = 0.062) and SLJ performance occurred as a result of training (p > 0.05). The major finding of this study was that PT gains subsequent to isokinetic resistance training did not influence functional performance. That open-chain training did not affect the performance of a closed-chain activity is unsurprising, but on these grounds of nonfunctionality, the use of moderate velocity isokinetic dynamometry in rehabilitation and performance assessment for closed-chain sports needs addressing in future research.