Ratings of affective valence closely track changes in oxygen uptake: Application to high-intensity interval exercise

Abstract High-intensity interval training (HIIT) has garnered attention because of the promise that it may confer health benefits with reduced time commitment compared to prescriptions calling for moderate-intensity continuous exercise. However, the value of HIIT for public health hinges on whether the high intensity of such regimens will be acceptable or tolerable. While the dual-mode theory predicts that exercise performed at an intensity exceeding critical power (i.e., as most HIIT protocols) will induce displeasure tied to the severe homeostatic perturbation, skeptics have countered that the empirical basis of the theory is limited to continuous exercise protocols and that the theory may not be applicable to intermittent exercise such as HIIT. Using four HIIT protocols, designed to expend either 80 % or 60 % of the finite work that can be performed above critical power over either 5-min or 3-min intervals, we demonstrate that affective valence closely tracks rapid changes in oxygen uptake. These data illustrate the link of affect to homeostatic perturbations and highlight the potential utility of ratings of affective valence as a tool for monitoring exercise stress and customizing training regimens.