Is There a Dose-Response Relationship between High-Intensity Interval Exercise (HIIE) Intensity and Affective...

The inverse relationship between exercise intensity and affective valence is well established for continuous exercise but not for high-intensity interval exercise (HIIE). The objective was to verify the dose-response relationship between exercise intensity and affective valence in HIIE sessions. Eleven young men underwent a vigorous-intensity continuous exercise (VICE) and three HIIE sessions at the same average intensity (70% of peak power-W_Peak) and duration (20 min) but with different amplitudes: 10 × [1 min at 90% W_Peak/1 min at 50% W_Peak]-HIIE-90/50; 10 × [1 min at 100% W_Peak/1 min at 40% W_Peak]-HIIE-100/40; 10 × [1 min at 110% W_Peak/1 min at 30% W_Peak]-HIIE-110/30. During the exercise sessions, psychophysiological variables were recorded (VO₂, VCO₂, heart rate, perceived exertion CR10, and Feeling Scale (FS)). Higher correlations were found between CR10 and FS for all conditions (VICE = -0.987; HIIE-90/50 = -0.873; HIIE-100/40 = -0.908; HIIE-110/30 = -0.948). Regarding the physiological variables, the %HR_Max presented moderate inverse correlations with FS for all exercise conditions (VICE = -0.867; HIIE-90/50 = -0.818; HIIE-100/40 = -0.837; HIIE-110/30 = -0.828) while the respiratory variables (%VO_2Peak and %VCO_2Peak) presented low-to-moderate correlations only for VICE, HIIE-90/50, and HIIE-100/40 (ranging from -0.523 to -0.805). Poor correlations were observed between the %VO_2Peak (r = -0.293) and %VCO_2Peak (r = -0.020) with FS. The results indicated that perceived exertion is more sensible than physiological variables to explain the intensity-affective valence relationship in HIIE sessions. RPE should be used for HIIE prescription with a focus on affect.