Energy expenditure and EPOC between water-based high-intensity interval training and moderate-intensity continuous training sessions in healthy women

Abstract

The present study compared the energy expenditure (EE) during and after two water aerobics protocols, high-intensity interval training (HIIT) and moderate continuous training (CONT). A crossover randomized design was employed comprising 11 healthy young women. HIIT consisted of eight 20s bouts at 130% of the cadence associated with the maximal oxygen consumption (measured in the aquatic environment) with 10s passive rest. CONT corresponded to 30 min at a heart rate equivalent to 90-95% of the second ventilatory threshold. EE was measured during and 30 min before and after the protocols and excess post-exercise oxygen consumption (EPOC) was calculated. Total EE during session was higher in CONT (227.62 ± 31.69 kcal) compared to HIIT (39.91 ± 4.24 kcal), while EE per minute was greater in HIIT (9.98 ± 1.06 kcal) than in CONT (7.58 ± 1.07 kcal). Post-exercise EE (64.48 ± 3.50 vs. 63.65 ± 10.39 kcal) and EPOC (22.53 ± 4.98 vs.22.10 ± 8.00 kcal) were not different between HIIT and CONT, respectively. Additionally, oxygen uptake had already returned to baseline fifteen minutes post-exercise. These suggest that a water aerobics CONT session results in post-exercise EE and EPOC comparable to HIIT despite the latter supramaximal nature. Still, CONT results in higher total EE.

Mechanistic and methodological perspectives on the impact of intense interval training on post‐exercise metabolism

“…Due to the intense nature of the protocol, it is often hypothesized that HIIT/SIT elevates EPOC to a greater extent than MICT, and over the course of the day may result in an energy deficit not accounted for in the estimated caloric expenditure associated with the session itself . However, as discussed in the present review, greater EPOC values have been consistently documented following SIT only, and equivocally following HIIT, compared to MICT, with the resultant increases in energy expenditure negligible in the immediate hour post‐exercise. Furthermore, these increases in energy expenditure are similar to, and sometimes greater than that which is induced by MICT at 24 hours.…”

“…19,[24][25][26][27] Furthermore, some studies suggest that HIIT results in elevated V O 2 compared to MICT and baseline at ~21 hours post-exercise, 28,31 while others have reported a return to baseline V O 2 levels within 1 hour post-exercise. 18,19,24,32 In contrast, the differences in V O 2 post-SIT compared to MICT are more pronounced, and SIT tends to produce greater EPOC magnitudes vs MICT at all time points, 24,25,33,34,42,43,75 with few exceptions. 32,44 These data support the established trend that SIT produces greater EPOC magnitudes than MICT protocols.…”

“…As with HIIT, there is strong evidence supporting the ability of SIT to elevate V O 2 above control levels post-exercise. Studies examining EPOC following SIT compared to no exercise or MICT with various protocols over several time frames are outlined in Tables 1 and 3 and demonstrate a consistent presence of EPOC in the recovery period compared to baseline levels 25,[33][34][35][36] or a no-exercise control day, 24,32,[37][38][39][40][41][42][43][44][45] with one exception. 46 Average total EPOC magnitude equates to ~6.8, ~1.7, and 2.6 L/h from 0.5-3 hours, 9 hours, and 24 hours post-SIT, respectively (Table 3).…”

“…In contrast to HIIT, many studies demonstrate larger EPOC magnitudes after SIT directly compared to MICT, 24,25,[33][34][35]40,42,43 with few others reporting no differences. 32,44 On average, the total EPOC magnitude equates to ~9.1 L, or ~6.3 L/h in the 0.5-3 hours following SIT, compared to ~5.9 L or ~3.8 L/h following MICT.…”

“…24,32,34,36,[38][39][40][41]44,46 Again, these values are greater than that which is seen following MICT at ~8.4 L total and ~2.9 L/h, demonstrating the ability of SIT to induce EPOC above control levels or compared to MICT post-exercise. Seven of the studies recorded a significantly elevated EPOC following SIT vs MICT, 24,25,[33][34][35]40,42,43 with the mean EPOC totaling to ~6.74 L/h. However, of the remaining three studies reporting no significant differences compared to control 46 or MICT, 32,44 mean EPOC was found to be ~2.7 L/h following SIT and ~1.7 L/h following MICT.…”