title: Effect of different knee starting angles on intersegmental coordination and performance in vertical jumps.
abstract: This study aimed to analyze the effect of different knee starting angles on jump performance, kinetic parameters, and intersegmental coupling coordination during a squat jump (SJ) and a countermovement jump (CMJ). Twenty male volleyball and basketball players volunteered to participate in this study. The CMJ was performed with knee flexion at the end of the countermovement phase smaller than 90° (CMJ(<90)), greater than 90° (CMJ(>90)), and in a preferred position (CMJ(PREF)), while the SJ was performed from a knee angle of 70° (SJ(70)), 90° (SJ(90)), 110° (SJ(110)), and in a preferred position (SJ(PREF)). The best jump performance was observed in jumps that started from a higher squat depth (CMJ(<90)-SJ(70)) and in the preferred positions (CMJ and SJ), while peak power was observed in the SJ(110) and CMJ(>90). Analysis of continuous relative phase showed that thigh-trunk coupling was more in-phase in the jumps (CMJ and SJ) performed with a higher squat depth, while the leg-thigh coupling was more in-phase in the CMJ(>90) and SJ(PREF). Jumping from a position with knees more flexed seems to be the best strategy to achieve the best performance. Intersegmental coordination and jump performance (CMJ and SJ) were affected by different knee starting angles.
authors.affiliation: Federal University of Amazonas, Manaus, Amazonas, Brazil.
authors.forename: Rodrigo G
authors.initials: RG
authors.lastname: Gheller
authors.affiliation: Biomechanics Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil. Electronic address: dalpupo@gmail.com.
authors.forename: Juliano
authors.initials: J
authors.lastname: Dal Pupo
authors.affiliation: Biomechanics Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Ache-Dias
authors.affiliation: Biomechanics Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
authors.forename: Daniele
authors.initials: D
authors.lastname: Detanico
authors.affiliation: University e-Campus, Novedrate, Italy; Tunisian Research Laboratory "Sports Performance Optimisation" National Center of Medicine and Science in Sports (CNMSS), Tunis, Tunisia.
authors.forename: Johnny
authors.initials: J
authors.lastname: Padulo
authors.affiliation: Biomechanics Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
authors.forename: Saray G
authors.initials: SG
authors.lastname: dos Santos
mesh_terms: D000054:Acceleration; D000328:Adult; D001490:Basketball / Q000502:physiology*; D001696:Biomechanical Phenomena / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D009048:Motor Skills / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D054798:Volleyball / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology; D055815:Young Adult
keywords: Continuous relative phase; Kinematic; Kinetic; Motor control; Power output