The quadriceps and hamstring muscles are the two primary movers of the knee during exercise, and due to their antagonistic relationship, the strength ratio (H:Q) is important for efficient knee mechanics. Fatigue is a factor that may alter the strength ratio, predisposing the active person to injury. This study examined the effect of fatigue on the H: Q ratio in 12 subjects that were tested on an isokinetic dynamometer, before and after inducing fatigue on a cycle ergometer during a 30 sec sprint. The H:Q does not significantly change within subjects, and between ergometers. Fatigue did not affect quadriceps but hamstrings strength declined, which may predispose it to injuries.