A comparison of two resistance exercise bouts of different intensities but equal work volume on excess post exercise oxygen consumption

This study compared the effect of low and high intensity resistance exercise bout of equal work output, to determine which produced the greatest exercise energy expenditure and excess post-exercise oxygen consumption (EPOC). Fourteen females performed a no-exercise baseline control (CN) session. In two other sessions subjects performed 2 sets of 15 repetitions for each exercise at 45% of their 8-RM during one session (LO) and 2 sets of 8 repetitions at 85% of their 8-repetition maximum (8-RM) during another session (HI). Measures for all three sessions included: heart rate (HR) and blood lactate ([La -]) pre-exercise, end of exercise and 20 min, 60 min and 120 min post-exercise; and ventilation volume (VE), oxygen consumption (VO2), and respiratory exchange ratio (RER), during exercise and at intervals 0--20 min, 45--60 min and 105--120 min post-exercise. Exercise VO2 was not significantly different between HI and LO intensity, but [La-], VE, and HR were significantly greater for HI. Total EPOC was greater for HI (2.33 LO2) compared to LO (1.34 LO2). During the 0--20 min post-exercise interval, the VE was significantly greater for the HI compared to the LO and CN. VE and HR for HI and LO were significantly greater than the CN. The RER, for the HI (1.07) and LO (1.05) were significantly higher than CN (0.86) during exercise, but HI, LO and CN were not significantly different at anytime post-exercise. The estimated caloric value of EPOC was 17.0 kcal for HI and 8.45 kcal for LO. These data indicate that when work volume is held constant and produces similar exercise energy expenditure, high intensity resistance exercise will produce a greater EPOC than low intensity resistance exercise.