Edgewood College, Natural Science and Nursing, Madison, WI 53711
Female athletes are at greater risk of knee injury than men. This risk may be attributed to hormonal influence, differing anatomy, or strategic differences in neuromuscular control. The risk for knee injury, particularly with regard to anterior cruciates ligament (ACL) injury, increases if the athlete is in a sport that requires frequent jumping, landing, turning, or cutting. Recent studies have shown that females can use neuromuscular training programs to “retrain” joints to move through mechanically advantageous positions. Plyometrics is a neuromuscular training regime that has been used to reduce the risk of knee injuries in elite volleyball players, and has the added benefit of improving peak jump height in these individuals. We investigated a similar plyometric training technique for the players on Edgewood College’s volleyball team. We hypothesized that players who were trained would improve their peak jump height and would improve body posture so that they would reduce their risk for knee injury. We used the following as indicators of improved body posture: two footed landing, minimal or no swaying of the upper body, continuous jumping motions, weight over toes. Participants in this study first performed a series of jumping tasks, which included 10 sequential blocking jumps. We video taped each series (in frontal and sagittal planes) and recorded joint angle at the hip, knee, and ankle, as well as peak jump height and our posture indicators (above). Participants then trained three times a week for three weeks using a standard plyometric regime (T. Hewitt). Following the three week program, participants repeated the jumping series and data were again recorded. Pre- and post-training video showed that players decreased knee flexion (squatting) following plyometric training. We also observed fewer one-footed landings, better overall balance, and a larger number of continuous jumps following the three week training program. Jump height was unchanged. This study provides us with information about the role neuromuscular training plays in reducing the risk of joint injury in volleyball players. This training program improved the Edgewood College volleyball players’ performance, and helped reduced the risk for a common joint injury.
[Abstract (DOC)]