Pelvic elevation induces vertical kinetic energy without losing horizontal energy during running single-leg jump for distance

Abstract

ABSTRACT In a running single-leg jump (RSLJ) for distance, the generation of vertical velocity without loss of horizontal velocity during the take-off phase is ideal, but difficult; however, we hypothesized that the pelvic rotation in the frontal plane achieved it. Here we show the effect of each segment rotation on the horizontal and vertical kinetic energies ( and ) of the centre of mass (CoM) during the take-off phase of an RSLJ for distance. We collected kinematic and ground-reaction-force data during RSLJs for distance by nine male long jumpers, involving an approximately 20-m approach in an outdoor field. We determined the components of the and changes due to each segment movement. Elevation of the pelvic free-leg side increased (0.53±0.16 J/kg, 9±3% of the total change). Pelvic axial rotation decreased , while pelvic elevation did not affect it (0.01±0.02 J/kg, no significant difference from zero). In contrast, forward rotations of the stance-leg shank and thigh decreased while simultaneously increasing . The results showed that pelvic elevation increased the vertical CoM velocity without causing a loss in horizontal velocity, although the lower-limb segments’ effects on the vertical and horizontal velocities exhibited a trade-off, as previously speculated. RSLJs for distance have been frequently assumed as sagittal movements. However, our findings highlight the importance of three-dimensional pelvic movement, particularly in the frontal plane, for controlling both the vertical and horizontal velocities. Highlights l We show the effect of each segment rotation on the horizontal and vertical kinetic energies ( and ) of the centre of mass during the take-off phase of a running single-leg jump for distance. l Elevation of the pelvic free-leg side increased but did not decrease , while the forward rotations of the stance-leg thigh and shank decreased , while simultaneously increasing . l We highlight the importance of pelvic movement in the frontal plane for controlling both the vertical and horizontal velocities with single-leg stance.