Physiological, Perceptual, and Affective Responses to Six High-Intensity Interval Training Protocols.

This study examined the extent to which different high-intensity interval training (HIIT) and sprint interval training (SIT) protocols could influence psychophysiological responses in moderately active young men. Fourteen participants completed, in a randomized order, three cycling protocols (SIT: 4 × 30-second all-out sprints; Tabata: 7 × 20 seconds at 170% ⋮O; and HIIT: 10 × 60 seconds at 90% HR) and three running HIIT protocols (4 × 4 minutes at 90%-95% HR, 5 × at v⋮O, and 4 × 1,000 meters at a rating of perceived exertion (RPE) of 8, from the OMNI-Walk/Run scale). Oxygen uptake (⋮O), heart rate, and RPE were recorded during each interval. Affective responses were assessed before and after each trial. The Tabata protocol elicited the highest ⋮O and RPE responses, and the least pleasant session-affect among the cycling trials. The v⋮O elicited the highest ⋮O and RPE responses and the lowest mean session-affect among the running trials. Findings highlight the limited application of SIT and some HIIT protocols to individuals with low fitness levels.