European Journal of Sport Science | 2019
Cardiorespiratory and perceptual responses of two interval training and a continuous training protocol in healthy young men
Abstract
Abstract High Intensity Interval Training (HIIT) can be performed with different effort to rest time-configurations, and this can largely influence training responses. The purpose of the study was to compare the acute physiological responses of two HIIT and one moderate intensity continuous training (MICT) protocol in young men. A randomised cross-over study with 10 men [age, 28.3\u2009±\u20095.5years; weight, 77.3\u2009±\u20099.3\u2005kg; height, 1.8\u2009±\u20090.1\u2005m; peak oxygen consumption (VO2peak), 44\u2009±\u200911\u2005mL.kg−1.min−1]. Participants performed a cardiorespiratory test on a treadmill to assess VO2peak, velocity associated with VO2peak (vVO2peak), peak heart rate (HRpeak) and perceived exertion (RPE). Then participants performed three protocols equated by distance: Short HIIT (29 bouts of 30s at vVO2peak, interspersed by 30s of passive recovery, 29\u2005min in total), Long HIIT (3 bouts of 4\u2005min at 90% of vVO2peak, interspersed by 3\u2005min of recovery at 60% of vVO2peak, 21\u2005min in total) and MICT (21\u2005min at 70% of vVO2peak). The protocols were performed in a randomised order with ≥48 h between them. VO2, HRpeak and RPE were compared. VO2peak in Long HIIT was significantly higher than Short HIIT and MICT (43\u2009±\u200911 vs 32\u2009±\u20098 and 37\u2009±\u20098\u2005mL.kg−1.min−1, respectively, P\u2009<\u20090.05), as well as peak HR (181\u2009±\u200910 vs 168\u2009±\u20098 and 167\u2009±\u200911, respectively, P\u2009<\u20090.05), and RPE (17\u2009±\u20094 vs 14\u2009±\u20094 and 15\u2009±\u20094, respectively, P\u2009<\u20090.05), with no difference between Short HIIT and MICT. In conclusion, Long HIIT promoted higher acute increases in VO2, HR and RPE than Short HIIT and MICT, suggesting a higher demand on the cardiorespiratory system. Short HIIT and MICT presented similar physiologic and perceptual responses, despite Short HIIT being performed at higher velocities.