Author(s): VENHORST, A., GUTJAHR, L., KAPPLER, T., OTT, T., MEYER, T., Institution: SAARLAND UNIVERSITY, Country: GERMANY, Abstract-ID: 2608

INTRODUCTION:
Current guidelines for exercise prescription are based on the training dose-response relationship and FITT principle. Given the efficacy of high-intensity exercise in eliciting superior adaptations in maximal oxygen consumption over 3-to-6-month interventions, such exercise is now also prescribed to physically inactive and overweight people. Yet such approach neglects sensory, affective and cognitive perceptions to varying degrees of physiological strain that underpin self-regulation of long-term exercise behavior. Thus, we applied a three-dimensional perceptual framework to investigate the integrated psychophysiological responses to high, vigorous, and moderate intensity as well as self-determined exercise.
METHODS:
Seventy-four insufficiently trained (24±28 min endurance training per week), normal (n=35, BMI 23±2) and overweight (n=39, BMI 29±3) men and women (each=37, 18-35 years) completed four equicaloric runs in semi-random order: 4 x 3 min high-intensity interval training (HIIT), vigorous intensity continuous (VICE), moderate intensity continuous (MICE) and self-paced (SELF) exercise over 27±0, 29±2, 36±2 and 31±2 min, respectively. Heart rate, relative oxygen consumption and blood lactate concentration as well as perceived strain, affective valence and action crisis were assessed at nine time points corresponding to peaks and nadirs of HIIT. Participants further rated remembered enjoyment and predicted training frequency 15 min post exercise.
RESULTS:
One-way ANOVA for running velocity and MANOVA for heart rate, oxygen consumption and lactate concentrations showed large trial effects on overall average [peak-and-end-rule average during HIIT] between HIIT, VICE, MICE and SELF, respectively: 8.4 [9.9], 8.9, 6.5 and 8.1 km/h, 167 [177], 172, 148 and 163/min, 41 [46], 43, 34 and 40 ml/min/kg and 6.9 [7.2], 4.4, 1.6 and 2.7 mmol/l. A MANOVA for perceived strain, affective valence and action crisis also found large trial effects: 13.3 [14.9], 14.7, 10.1 and 12.2 A.U., 0.8 [0.2], 0.6, 3.1 and 2.8 A.U. and 3.6 [4.2], 3.8, 1.8 and 2.1 A.U.; so did a MANOVA for remembered enjoyment and predicted training frequency: -0.6, -0.2, 3.2 and 2.7 cm and 2.0, 2.1, 3.0 and 2.9 sessions per week. Pairwise comparisons showed greater [smaller] cardiovascular, respiratory and perceived strain during VICE vs HIIT and consistently greater metabolic strain during HIIT. Affective valence, action crisis, remembered enjoyment and predicted training frequency showed highly significant differences between HIIT/VICE and MICE/SELF but not between HIIT vs VICE or MICE vs SELF.
CONCLUSION:
Affective valence and action crisis provide additional, integrated perceptual information that closely aligns with remembered enjoyment and predicted training frequency, thus contributing to better understanding self-regulation of exercise behavior. Also, self-determined perceptually guided exercise is associated with a favorable stimulus-response relationship and may be a suitable alternative to prescribing exercise.