BACKGROUND & OBJECTIVE
Young female athletes experience non-contact ACL injuries at relatively high rates - about five times higher than that of young males participating in the same sport. Such injuries often occur during landing and cutting movements that cause dynamic lower extremity valgus, which typically involves a combination of the following movements: hip adduction and internal rotation, knee abduction, tibial external rotation and anterior translation, and ankle eversion. Previous studies have shown that neuromuscular training (NMT) programs can decrease ACL injury rates in young female athletes in soccer, basketball, and volleyball. The success of these programs may due to changing landing biomechanics. Netball is a game with high rates of ACL injury, as players must often rapidly decelerate and stop after receiving the ball. This study examined the effects of an NMT program on lower extremity biomechanics in young female netball players.
23 female athletes aged 11-13 participated in the study and were divided into two groups. Each group engaged in regular netball training, but the experimental group also received six weeks of NMT training. Before and after NMT training, landing biomechanics were assessed on two landing tasks: drop vertical jump with double leg landing, and a double leg broad jump with a single leg landing. The assessments were vertical ground reaction force and three-dimensional lower-extremity kinematics. The NMT training consisted of three one-hour sessions per week for six weeks. Each session had three basic components: (1) a dynamic warm up (e.g. carioca, superman, high knee grab); (2) plyometric exercises (e.g. 1/2 squat jump, spin jump, etc.); and basic strength training (e.g. bench press, back squat, lunge, etc).
The group that performed NMT training improved landing mechanics in several respects. They made large reductions in peak vertical ground reaction force on both landing tasks. During the double-leg landing, they increased bilateral knee distance at peak knee flexion, indicating