title: Asymmetry between the Dominant and Non-Dominant Legs in the Kinematics of the Lower Extremities during a Running Single Leg Jump in Collegiate Basketball Players.
abstract: The present study aimed to clarify the asymmetry between the dominant (DL) and non-dominant takeoff legs (NDL) in terms of lower limb behavior during running single leg jumps (RSJ) in collegiate male basketball players in relation to that of the jump height. Twenty-seven players performed maximal RSJ with a 6 m approach. Three-dimensional kinematics data during RSJ was collected using a 12 Raptor camera infrared motion analysis system (MAC 3D system) at a sampling frequency of 500 Hz. The symmetry index in the jump heights and the kinematics variables were calculated as {2 × (DL - NDL) / (DL + NDL)} × 100. The run-up velocity was similar between the two legs, but the jump height was significantly higher in the DL than in the NDL. During the takeoff phase, the joint angles of the ankle and knee were significantly larger in the DL than the NDL. In addition, the contact time for the DL was significantly shorter than that for the NDL. The symmetry index of the kinematics for the ankle joint was positively correlated with that of jump height, but that for the knee joint was not. The current results indicate that, for collegiate basketball players, the asymmetry in the height of a RSJ can be attributed to that in the joint kinematics of the ankle during the takeoff phase, which may be associated with the ability to effectively transmit run-up velocity to jump height. Key pointsAsymmetry of height during running single leg jump between two legs is due to the behavior of the ankle joint (i.e. stiffer the ankle joint and explosive bounding).The dominant leg can transmit run-up velocity into the vertical velocity at takeoff phase to jump high compared with the non-dominant leg.Basketball players who have a greater asymmetry of the RSJ at the collegiate level could be assessed as non-regulars judging by the magnitude of asymmetry.
authors.affiliation: Graduate School of Physical Education, National Institute of Fitness and Sports in Kanoya , Kagoshima, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Sugiyama
authors.affiliation: Graduate School of Physical Education, National Institute of Fitness and Sports in Kanoya , Kagoshima, Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Kameda
authors.affiliation: Graduate School of Physical Education, National Institute of Fitness and Sports in Kanoya , Kagoshima, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kageyama
authors.affiliation: National Institute of Fitness and Sports in Kanoya , Kagoshima, Japan.
authors.forename: Kazufusa
authors.initials: K
authors.lastname: Kiba
authors.affiliation: National Institute of Fitness and Sports in Kanoya , Kagoshima, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kanehisa
authors.affiliation: National Institute of Fitness and Sports in Kanoya , Kagoshima, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Maeda
keywords: Jump height; bilateral difference; joint kinematics; symmetry index