Impact and Push-Off Force Symmetry in Dominant Versus Non-Dominant Legs During a Jump Landing/Cutting Task

Our goal was to examine ground reaction forces (GRF) following a series of unanticipated jump landing and cutting tasks (JLC) and the differences in these GRF’s associated with leg dominance. Nine recreationally active (at least 3x/week of running, cycling, aerobics, or recreational sports participation) right leg dominant females with no history of lower extremity injuries participated in the current study. Each subject conducted a set of 12 (JLC) trails, four (JLC’s) to three different directions. The subjects either performed a left cutting (LC), right cutting (RC) at 30 degrees from center or a straight ahead center cutting (CC) maneuver. Landing impact (IP) and push-off (PO) forces for both the dominant and nondominant (IPN, IPD, PON, POD) were compared using ANOVA with repeated measures and post-hoc comparisons with t-tests. Significant differences were found between dominant and non-dominant leg IP and PO peak GRF during LC task. No significant differences were found for all other JLC tasks. These data suggest that the more extensive the change of direction opposite the dominant leg, the greater the forces acting on the dominant leg versus the forces felt during a change of direction towards the nondominant leg of the subject. This would suggest that the amount of forces the non-dominant leg can accommodate is less than the dominant leg, which could play a role in anterior cruciate ligament injury.