Patients who are diagnosed with an isolated tear of the anterior cruciate ligament and scheduled for arthroscopic reconstruction using bone-patellar tendon-bone autograft will be recruited to participate.

All subjects will be invited to participate in 2 weeks (2 supervised sessions per week) prior to their surgery. Each session will include supervised therapeutic exercises. Subjects will be randomly assigned to receive continuous transcutaneous electrical nerve stimulation (TENS) during each session or knee joint cryotherapy prior to each exercise session. The investigators will measure quadriceps function before and after this 2-week intervention (both sessions occur prior to reconstruction surgery). This study will also have a true control group that will not receive either exercise of modality intervention. The investigators will collect subjective and objective outcomes data at regularly scheduled post-operative visits.

Inclusion Criteria:

1. Complete ACL rupture
2. Age 15-55

Exclusion Criteria:

1. Persons who cannot tolerate knee joint TENS.
2. Persons who have a known allergy to cryotherapy
3. Patients who are pregnant or who plan on getting pregnant during the 12-month follow-up period.