This is a crossover phase 4 study to evaluate the impact of blood flow restriction on immunometabolism and gene expression in immune cells in individuals undergoing rehabilitation from anterior cruciate ligament reconstruction.

This is a single-blind crossover phase 4 study in which participants will be randomized as to the order in which each of two sessions are completed. Although all analyses will be performed by a blinded investigator and participants will wear an uninflated AirBand as the control intervention during the session in which BFR is not performed, participants will likely know which of the two interventions is being performed on which study day. The AirBands will be placed at each of the two training sessions and inflated while an ultrasound probe is placed over the femoral artery. The cuff will be inflated until the artery reaches 60% occlusion. The force will be applied using a wireless Bluetooth signal; participants will not be asked to adjust the device. Participants will be observed by a certified Personal Therapist throughout the training session in order to determine compliance and ensure safety as is standard protocol for a physical therapy session. The study team hypothesizes that the BFR will: * Promote an anabolic immunometabolic signature, reflected in the composition of serum amino acid concentrations and anabolic hormone content * Enhance anaerobic glycolysis in leukocytes (which has been associated with increased activation in other settings (Marelli-Berg and Jangani, 2018; Pearce and Pearce, 2013)) * Increase leukocyte glucose and pyruvate concentrations, which corresponds to acute energy provision to promote repair