title: Performing the vertical jump: movement adaptations for submaximal jumping.
abstract: The purpose of this study was to gain insight into the kinematics and kinetics of the vertical jump when jumping for different heights and to investigate movement effectiveness as a criterion for movement control in submaximal jumping. In order to jump high a countermovement is used and large body segments are rotated, both of which consume energy which is not directly used to gain extra jump height. It was hypothesized that the energy used to reach a specified jump height is minimized by limiting the non-effective energy consumed. Standing vertical jumps attempting 100%, 75%, 50%, and 25% of maximal height were performed by a group of 10 subjects. Force and motion data were recorded simultaneously during each performance. We found that jump height increased due to increasing vertical velocity at take off. This was primarily related to an increase in countermovement amplitude. As such, flexion amplitude of the hip joint increased with jump height whereas the ankle and knee joint flexion did not. These findings revealed that for submaximal jumping a consistent strategy was used of maximizing the contribution of distal joints and minimizing the contribution of proximal joints. Taking into account the high inertia of proximal segments, the potential energy deficit due to countermovement prior to joint extension, the advantageous horizontal orientation of the foot segment during stance and the tendon lengths in distal muscles, it was concluded that movement effectiveness is a likely candidate for the driving criterion of this strategy.
authors.affiliation: Department of Movement and Sport Sciences, Faculty of Medicine and Health Sciences, Ghent University, Watersportlaan 2, B-9000 Gent, Belgium. jos.vanrenterghem@ugent.be
authors.forename: Jos
authors.initials: J
authors.lastname: Vanrenterghem
authors.forename: Adrian
authors.initials: A
authors.lastname: Lees
authors.forename: Matthieu
authors.initials: M
authors.lastname: Lenoir
authors.forename: Peter
authors.initials: P
authors.lastname: Aerts
authors.forename: Dirk
authors.initials: D
authors.lastname: De Clercq
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D001696:Biomechanical Phenomena; D006801:Humans; D007700:Kinetics; D008297:Male; D009068:Movement