engleski

Optimum Load in Various Vertical Jumps Support the Maximum Dynamic Output Hypothesis

he aim was to generalize the maximum dynamic output (MDO) hypothesis [i. e., the muscle power output in vertical jumps (VJ) is maximized when loaded with one’s own body mass] to variety of VJ. We hypothesized that the subjects’ own body (a) would be the optimal load for maximizing the power output (i. e., the no-load condition) and also (b) reveal the maximum benefits of stretch-shortening cycle (SSC). 13 participants performed the maximum squat and various counter-movement jumps when loaded by approximately constant external force ranging from −40% to + 40% of their body weight (BW). Regarding the first hypothesis, the differences in both the peak and mean power recorded under different load magnitudes revealed maxima close to no-load condition (i. e., from −3% BW to + 8% BW ; R2=0.65–0.96 ; all P<0.01). Regarding the second hypothesis, the differences in performance between VJ executed with and without SSC also revealed maxima close to no-load conditions (0–2% BW), while the same differences in the power output were observed under relatively low positive loads (14–25% BW ; R2=0.56–0.95 ; all P<0.01). The findings support the concept that maximal power output occurs close to one’s own body mass during VJ with and without SSC, thereby providing additional support to MDO hypothesis.

power ; MDO hypothesis ; counter-movement ; force-velocity relationship

nije evidentirano