Background: To empirically evaluate a cognitive affective model of physical activity. This bidirectional, cyclical model hypotheses that executive control processes directly influence habitual engagement in exercise and also directly subserve the exercise-induced affective response to acute exercise associated with future physical activity. Methods: The present study employed a one-week prospective, multi-site design. Participant recruitment and data collection occurred at two separate University sites (one in the United States and the other in Canada). Participants completed a bout of treadmill exercise, with affect and arousal assessed before, during and after the bout of exercise. Subjective and objective measures of executive function were assessed during this visit. Following this laboratory visit, seven days of accelerometry were employed to measure habitual engagement in physical activity. Results: Within our inactive, young adult sample, we observed some evidence of 1) aspects of executive function were associated with more light-intensity physical activity in the future (1-week later) (r = 0.36, 95% CI = -0.03 to 0.66, P = 0.07), 2) aspects of executive function were associated with post-exercise affect (r = -0.39, 95% CI = -0.67 to -0.03, P = 0.03) and forecasted affect (r = 0.47, 95% CI = 0.11 to 0.72, P = 0.01), and 3) aspects of acute exercise arousal and affect were associated with current mild-intensity physical activity behavior (r = 0.41, 95% CI = 0.04 to 0.68, P = 0.03). Conclusion:We demonstrate partial support of a cognitive-affective model of physical activity.