Interventions to Enhance Quadriceps Output After ACLR

The investigators are interested in determining what treatments are effective in reducing inhibition after anterior cruciate ligament (ACL) surgery and helping people increase quadriceps strength. Two interventions that are often used clinically are neuromuscular electrical stimulation (NMES) and vibration. This is a study of how effective these treatments are, whether they work the same for everyone, and if one is better than the other. 22 participants will be enrolled and on study for 2 to 3 weeks.

Inclusion Criteria: * Have undergone ACLR within the previous 4 months * Are at least 2 months post-ACLR Exclusion Criteria: * A history of ACLR on both legs * Since the most recent ACLR: * secondary lower extremity surgery * leg or foot fracture * Unable to walk without an assistive device * Pain of greater than 5/10 during quadriceps strengthening exercises with the surgical limb * Cannot achieve 90 degrees of knee flexion with the surgical limb * People with contraindications to NMES * Anyone who had a previous skin reaction to NMES or attempted but could not tolerate NMES * Peripheral neuropathy or other neurological conditions