Knee injuries, especially those to the ACL, are common among physically active people. These injuries are frequently treated with surgical reconstruction (ACL reconstruction; ACLR). While ACLR restores stability it does not protect against future injury, long-term pain, disability, and arthritis associated with these injuries. Our study is going to examine new ways to provide feedback about the way people move to determine if these are better at modifying movement patterns that are known risk factors of posttraumatic osteoarthritis development than current standard treatments. If you participate, you will be asked to undergo a movement analysis in a research laboratory while you perform tasks such as walking and hopping. After this initial assessment, you will be randomly allocated to one of 2 treatment groups. Each treatment group will perform 4 weeks (3x/week) of exercises to change the way people walk. Participants will then report for follow-up movement analysis testing 1- and 4-weeks after completing the intervention.

Inclusion Criteria:

• history of primary, unilateral ACL reconstruction 6-24 months prior to enrollment
• cleared to return to full activity by treating orthopedic surgeon

Exclusion Criteria:

• Body mass index >35 kg/m2
• History of musculoskeletal injury sustained 3 months prior to enrollment
• Current participation in formal post-operative rehabilitation