2.3.4. Resistance Exercise Protocols
The two resistance exercise protocols, BFR and CTRL, consisted of high-intensity barbell back-squats (75% 1RM) with and without blood flow restriction, respectively. During both protocols, participants performed four sets of barbell back-squats at 75% of 1RM with three minutes rest between sets. Each set was performed to failure, with the number of repetitions successfully completed recorded for each set. Prior to the BFR protocol, participants were fitted with inflatable pneumatic cuffs (11.5 cm width) positioned within 4 inches of the inguinal crease on both legs. Next, LOP was determined by the Delfi Personalized Tourniquet System II (PTS II) (Delfi Medical, Vancouver, BC, Canada), with participants in a seated position and each leg measured in turn. During the BFR protocol, bilateral occlusion at 80% LOP was applied to the lower limbs. The cuffs were inflated 30 s before beginning the first set and remained inflated until the completion of the second set, at which point the cuffs were deflated, allowing for approximately 2 min of reperfusion between these sets. The cuffs were re-inflated 30 s prior to the start of set 3 and remained inflated until 2 min after set 4 was completed.