title: Determinants of countermovement jump performance: a kinetic and kinematic analysis.
abstract: This study aimed to investigate the contributions of kinetic and kinematic parameters to inter-individual variation in countermovement jump (CMJ) performance. Two-dimensional kinematic data and ground reaction forces during a CMJ were recorded for 18 males of varying jumping experience. Ten kinetic and eight kinematic parameters were determined for each performance, describing peak lower-limb joint torques and powers, concentric knee extension rate of torque development and CMJ technique. Participants also completed a series of isometric knee extensions to measure the rate of torque development and peak torque. CMJ height ranged from 0.38 to 0.73 m (mean 0.55 ± 0.09 m). CMJ peak knee power, peak ankle power and take-off shoulder angle explained 74% of this observed variation. CMJ kinematic (58%) and CMJ kinetic (57%) parameters explained a much larger proportion of the jump height variation than the isometric parameters (18%), suggesting that coachable technique factors and the joint kinetics during the jump are important determinants of CMJ performance. Technique, specifically greater ankle plantar-flexion and shoulder flexion at take-off (together explaining 58% of the CMJ height variation), likely influences the extent to which maximal muscle capabilities can be utilised during the jump.
authors.affiliation: a School of Sport, Exercise and Health Sciences , Loughborough University , Loughborough , UK.
authors.forename: Stuart
authors.initials: S
authors.lastname: McErlain-Naylor
authors.forename: Mark
authors.initials: M
authors.lastname: King
authors.forename: Matthew Thomas Gerard
authors.initials: MT
authors.lastname: Pain
mesh_terms: D000328:Adult; D000842:Ankle / Q000502:physiology; D001696:Biomechanical Phenomena; D006615:Hip / Q000502:physiology; D006801:Humans; D007717:Knee / Q000502:physiology; D035002:Lower Extremity / Q000502:physiology*; D008297:Male; D009068:Movement; D053580:Muscle Strength / Q000502:physiology; D059385:Plyometric Exercise; D011187:Posture; D012782:Shoulder / Q000502:physiology; D013647:Task Performance and Analysis; D019415:Torque; D055815:Young Adult
keywords: countermovement jump; kinematics; kinetics; rate of torque development; technique