title: Optimum load in various vertical jumps support the maximum dynamic output hypothesis.
abstract: The 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.
authors.affiliation: Faculty of Sport and Physical Education, The Research Center, University of Belgrade, Belgrade, Serbia.
authors.forename: D
authors.initials: D
authors.lastname: Suzovic
authors.forename: G
authors.initials: G
authors.lastname: Markovic
authors.forename: M
authors.initials: M
authors.lastname: Pasic
authors.forename: S
authors.initials: S
authors.lastname: Jaric
mesh_terms: D054874:Athletic Performance / Q000502:physiology*; D001835:Body Weight; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology; D055815:Young Adult