Objective: There is a paucity of research concerning energy expenditure during and after circuit weight training (CWT). There is evidence that duration of rest between sets affects metabolic responses to resistive exercise. The purpose of the study was to determine the effect of rest-interval duration upon the magnitude of 1 h of excess postexercise oxygen consumption (EPOC).
Methods: Seven healthy men completed two randomized circuit weight training sessions using 20-s and 60-s rest intervals (20 RI, 60 RI). Sessions included two circuits of eight upper and lower body resistive exercises in which 20 repetitions were performed at 75% of a previously determined 20 repetition maximum.
Results: The 1 h EPOC of 10.3 +/- 0.57 L for the 20 RI session was significantly higher than 7.40 +/- 0.39 L for the 60 RI session. The net caloric expenditure during 1 h of recovery from the 20 RI session was significantly higher than that of the 60 RI session (51.51 +/- 2.84 vs 37.00 +/- 1.97 kcal); however, total gross energy expenditure (exercise + 1 h recovery) was significantly greater for the 60 RI protocol (277.23 kcal) than the 20 RI protocol (242.21 kcal).
Conclusion: Data demonstrate that shortening the rest interval duration will increase the magnitude of 1 h EPOC from CWT; however, the exercise + recovery caloric costs from CWT are slightly greater for a longer rest interval duration protocol. These data suggest that total caloric cost be taken into account for CWT.