Examining the acceptability of interval and endurance exercise training protocols for promoting exercise participation

Abstract

Compared to endurance training (ET), high-intensity interval training (HIIT) and moderate-intensity interval training (MIIT) are time efficient methods of improving fitness. However, interval training is significantly more intense than ET and the acceptability of these protocols for increasing exercise participation is unclear. Thus, we examined 11 participants' (19.9±1.1 yrs) preference for and social cognitive response to each protocol (e.g. task and scheduling self-efficacy). Following a ramp test to determine peak work rate (PWR), participants completed, in random order, one session of HIIT (8x1min at 120% PWR, 2min recovery), MIIT (10x4min at 90% PWR, 2min recovery), and ET (30min+4x13min at 65% PWR, 2min recovery). In a survey two weeks after completing all 3 protocols, 44% of participants preferred HIIT and 44% preferred ET. Repeated measures ANOVA with post hoc tests revealed that participants' anticipated enjoyment, affective attitudes, and task and scheduling self-efficacy were greater for HIIT and ET vs. HIIT, p<0.05. Greater intentions to implement HIIT and ET vs. MIIT both once (3.9±1.8 and 4.8±1.7 vs. 2.8±1.7, p<0.05) and twice (3.3±1.4 and 3.7±1.6, vs. 2.3±1.3, p<0.05) per week were reported. Participants reported greater positive outcome expectancies for ET vs. MIIT (27.5±6.0 vs. 20.8±8.4,p<0.05). This suggests that HIIT and ET elicit a greater effect on social cognitive predictors of behaviour versus MIIT despite differences in intensity and duration.