Differences in Oxygen Uptake between Equivalent Resistance Training Protocols: Sets vs. Reps

We examined the energy costs of different resistance training protocols where exercise and recovery periods were equated: 48 total seconds of exercise and 210 seconds of between-set recovery. Two separate investigations were carried out at 65% of a 1 repetition maximum (1RM): back squat (7 men, 3 women) and bench press (9 men). Lifting cadence for concentric and eccentric phases was set at 1.5 sec each with 30 sec between-set recovery periods for the 8 sets, 2 reps protocol (sets) and a 3 min and 30 sec between-set recovery period for the 2 sets, 8 reps protocol (reps). The amount of oxygen consumed during lifting and between-set recovery periods was significantly greater for sets vs. reps protocol for both the back squat (+41%) and bench press (+27%) (p = 0.0001). Moreover, the total aerobic cost including the after-lifting excess post-exercise oxygen consumption (EPOC) was larger for the increased sets protocol for both the squat (+27%, p = 0.01) and bench press (+29%, p = 0.04). Total energy costs - aerobic plus anaerobic, exercise and recovery - were not different among sets or reps protocols. We conclude that a greater volume of oxygen is consumed with a lower repetition, increased number of sets resistance training protocol. We suggest that more recovery periods promote a greater potential for fat oxidation.