A comparison of lumbosacral loads during static and dynamic activities

A biomechanical model to determine the loads at the lumbosacral joint was developed. This model was used to determine the lumbosacral loads during two specific activities--a stable standing posture representing a static activity, and a normal level walk representing a dynamic activity. This study involved ten healthy and young male subjects. The results obtained indicated that the lumbosacral loads during a stable standing posture was in the range of 0.82 to 1.18 times body-weight, with a mean of 1.03 (+/- 0.11) times body-weight. In comparison, during a normal level walk the lumbosacral loads were in the range between 1.41 and 2.07 times body-weight, with a mean of 1.61 (+/- 0.24) times body-weight. The walking speed of these subjects varied between 0.96 and 1.48 ms-1, with a mean of 1.25 (+ 0.18) ms-1. Results in this study indicated that there was a significant difference (p < 0.005) between the means of the lumbosacral loads of these two specified activities. An increase of 56.3% between means of the static to the dynamic case was observed.