Cognitive Fatigue, Humor, and Physical Activity: A Field Experiment Testing Whether Humorous Messages Promote Walking in Cognitively Fatigued Individuals.

Despite the success of humorous messages in various health interventions, its role in promoting physical activity (PA) remains understudied. This study addresses this gap by investigating the effectiveness of humorous messages in a 2-week smartphone-based intervention aimed at promoting walking behavior, particularly amongst cognitively fatigued individuals. Female participants (n = 57; M_age = 32.00; SD = 4.385) received humorous, nonhumorous, or a mix of both messages (in the form of memes) via a study-specific application, with cognitive fatigue measured daily. Panel linear regression models revealed a significant positive interaction between cognitive fatigue and message type. Our results suggest that the resilience of humorous messages to cognitive fatigue and their potential as motivational tools position them as a more robust choice for promoting PA. Importantly, when cognitively fatigued individuals received humorous messages, their walking behaviors showed no significant change, in contrast to the detrimental impact of nonhumorous messages on exercise. Recognizing the differential effects of cognitive fatigue on message effectiveness and considering the potential of humorous messages as motivational tools offers a valuable perspective for tailoring interventions to individual states.