Timing of lower extremity motions during barefoot and shed running at three velocities

This study investigates the timing differences between subtalar and knee joint movement of 9 male subjects while running barefoot and shed at three velocities. An alternative approach is used by dividing the pronation curve into 3 phases. Consequently, the timing of the maximum pronation phase was evaluated, not just the event of the maximum pronation value. Statistical differences were tested using the General Linear Method and paired t tests (p less than or equal to .05). The extension of the knee starts both barefoot and shed significantly earlier than the resupination phase, individual analysis shows that a larger time discrepancy between knee extension and the end of pronation mainly depends on the presence of bimodal pronation curves. The relative time differences significantly diminish with increased running velocity. Results suggest that by using this alternative approach, more detailed and useful information is available to describe the time relationship between flexion-extension of the knee and pro-supination.