Associations Between Expectations Regarding Psychological Well-being Response To Exercise And Observed Total Mood Disturbance Responses To Acute Low-intensity Aerobic Exercise.

: The influence of expectations on mood responses to acute aerobic exercise remains unclear. Elucidating this influence could lead to a better understanding of the true effect of exercise on mood responses and consequent priming of expectations to potentially enhance responses. PURPOSE: To quantify associations between expectations regarding psychological well-being response to exercise and actual total mood disturbance (TMD) responses to acute low-intensity aerobic exercise (AE). METHODS: 30 young adults (22.5 ± 3.9 yrs) were randomized to 20-min of low-intensity (10%-40% heart rate reserve continuously monitored with a Polar monitor) treadmill walking (n = 15) or 20-min of seated quiet rest (n = 15). TMD was measured with the Profile of Mood States - Brief Form pre- and 10-min-post conditions. Expectations regarding psychological well-being response to exercise were measured with the Expected Psychological Outcomes of Exercise before each condition. Consistent with previous evidence and guidance, expectations regarding psychological well-being response to exercise were matched with TMD. Analyses reported here focus only on exercise participants. Paired samples t-test and Hedges’ g effect sizes (95%CI) quantified differences between time points, and positive effect sizes represent improvement. Spearman’s rank correlations quantified associations between expectations and mood responses (i.e., change scores). RESULTS: There were large, significant changes in total mood disturbance pre- and 10-min-post low-intensity treadmill walking (t(14) = 3.82, p < 0.002, g = 0.93, 95%CI: 0.33, 1.51). There was a moderate-to-strong, significant association between expectations regarding psychological well-being response to exercise and actual change in total mood disturbance (rho = -0.72, p < 0.002). CONCLUSIONS: Preliminary findings suggest that reductions in total mood disturbance were influenced by expectations of psychological well-being response to exercise, such that expectations of improved psychological-well-being in response to exercise were associated with reduced total mood disturbance. These findings support potential manipulation and priming of expectations regarding exercise response to enhance mood responses to exercise, even at low exercise doses.