Determining the Effects of Non-invasive Brain Stimulation to Improve Quadriceps Muscle Function After ACL Reconstruction

After knee surgery for a torn ACL, many women struggle with weak thigh muscles for years, partly due to reduced brain signals to these muscles. Our research tests a new approach to improve recovery by using low-level brain stimulation to boost these signals. The investigators will study 42 women, aged 18-35, who had ACL surgery. They'll be split into two groups: one receiving real brain stimulation and another getting a placebo, both during thigh-strengthening exercises. Over six sessions, the investigators measure thigh muscle strength, speed, and steadiness, plus two brain signal measures, using special equipment. The investigators will also check if stronger brain signals lead to better muscle performance, especially in women. Our goal is to show that this new method strengthens thigh muscles better than standard rehab, helping women recover better after surgery. If successful, this could improve physical therapy for women recovering from ACL surgery, making daily activities and return to sport easier.