The purpose of this study was to determine the effects of the McDavid Knee Brace on forward and backward running kinematics and ground reaction forces. The subjects were 10past history of knee problems or any other physical disabilities that could affect their performance. The subjects were unpaid volunteers. Stride length and stride frequency values were determined during forward and backward treadmill run under each experimental condition (with a brace and without a brace). An ANOVA indicated no significant knee brace effect for either forward or backward treadmill running stride length or stride frequency. In the second phase of this study, ground reaction forces were determined for each experimental condition. The ground reaction peak forces under each experimental condition were not significantly different during either forward or backward running. Other statistical analysis of other dependent variables of forward and backward running indicated no significant bracing effect for ankle, knee and hip angular acceleration, angular displacement and angular velocity. Within the limitation of this study it is concluded that the McDavid Knee Brace had no effect on forward or backward running kinematics or ground reaction forces.