Optimizing Plyometric Training for Functional Recovery Post-ACL Reconstruction

While surgical anterior cruciate ligament reconstruction (ACLR) of the knee restores passive stability, studies are showing consistently poor long-term outcomes. Unusually high risks of early-onset osteoarthritis and re-injury, and low rate of return to sport following ACLR all seem to be related to a chronic tendency to land stiff-legged from a jump or hop, which itself may be due to fear of re-injury. Decreased knee bending for force absorption simultaneously decreases performance level and increases risk for injury and arthritic changes. The purpose of the proposed study is to compare a current best-practice plyometric training program to one utilizing body weight support to increase repetition and improve performance in the initial phases. The investigators hypothesize that we will see larger improvements in absorptive capacity of the knee and better confidence in activity immediately following body weight support training, as well as improved retention of training effects after a two-month period.