Abstract

The purpose of this study was to compare the biomechanical and physiological responses to two low impact (walking and high intensity walking at 2.1 m/s) and two high impact (jogging at 2.1 m/s and running at 2.9 m/s) modes of locomotion commonly used in aerobic dance classes. Maximal oxygen consumption and steady state submaximal oxygen consumption were measured for each of the modes of locomotion. Subjects were then filmed at 100 Hz as they performed each of these locomotor modes, that were matched for velocity with the respective treadmill tests, such that their right foot impacted a force platform during progression across the laboratory. A one way analysis of variance with repeated measures was used to test for task effects and contrast transformation post hoc comparisons were performed between the modes of locomotion if a significant main effect was attained. Significant kinematic differences were seen in cycle duration, stride length, vertical displacement of the centre of mass, leg angles and knee and hip joint angles between the modes of locomotion. These kinematic variations were at least in part responsible for the differences in the cardiorespiratory stresses and ground reaction forces produced by the four modes of locomotion. All four movement patterns stressed the cardiorespiratory system above the minimum guidelines for training (50 of VO2max) recommended by the American College of Sports Medicine (ACSM 1986). Verf.-Referat