Low- Versus High-Intensity Plyometric Exercise During Rehabilitation After Anterior Cruciate Ligament Reconstruction

Background:Plyometric exercise is used during rehabilitation after anterior cruciate ligament (ACL) reconstruction to facilitate the return to sports participation. However, clinical outcomes have not been examined, and high loads on the lower extremity could be detrimental to knee articular cartilage.Purpose:To compare the immediate effect of low- and high-intensity plyometric exercise during rehabilitation after ACL reconstruction on knee function, articular cartilage metabolism, and other clinically relevant measures.Study Design:Randomized controlled trial; Level of evidence, 2.Methods:Twenty-four patients who underwent unilateral ACL reconstruction (mean, 14.3 weeks after surgery; range, 12.1-17.7 weeks) were assigned to 8 weeks (16 visits) of low- or high-intensity plyometric exercise consisting of running, jumping, and agility activities. Groups were distinguished by the expected magnitude of vertical ground-reaction forces. Testing was conducted before and after the intervention. Primary outcomes ...