Ankle bracing has not been studied for its effects of knee joint kinematics and kinetics in the adolescent female athlete. The hypothesis is: A) A statistically significant mean increase of knee joint valgus and extensor moments and valgus angles would be found in the braced group during the drop vertical jump and the single log hop tests and B) A statistically significant mean decrease in knee joint varus and extensor moments and valgus angles will be found between pre- and post-test acclimation periods in the braced condition.