THE EFFECTS OF EXERCISE ON LIGAMENTOUS STIFFNESS IN THE WRIST

The purpose of this study was to determine if exercise alters wrist jo int laxity, as measured by the mechanical behavior of the scaphoid bon e. The load-displacement behavior of the scaphoid was studied in the p almar-dorsal direction in both wrists of 7 healthy volunteers (n = 14) before and after 2 exercise protocols (grip and push-up). When compar ed to the rested values, both exercise protocols significantly increas ed the displacement at 40 N by 47% (grip) and by 34% (push-up). Accord ingly, the stiffness decreased significantly by 36% (grip) and by 32% (push-up). partial recovery was documented after 1 hour of rest and th ere were no differences between any of the groups after 24 hours of re st. The increase in laxity documented during these exercise protocols reduces the ligament loads at comparable wrist positions and may there by reduce the likelihood of traumatic ligamentous injury during partic ipation in strenuous activity or sports.