A daily exercise prescription when work gets tough : The moderating effect of work demands on the relationship between daily physical exercise and next-day well-being and job performance.

Physical exercise is widely recognized for its benefits to individuals’ general health, yet its implications for in-role and extrarole job performance, especially on demanding workdays, have rarely been explored. This oversight is concerning as high work demands can deter employees from exercising when they are unaware that exercise can improve their job performance on demanding workdays. In this research, we draw on the effort–recovery model to propose that daily physical exercise not only promotes next-day well-being but also enhances next-day in-role job performance and extrarole organizational citizenship behavior (OCB) by fostering positive affect and work engagement the following day. Moreover, these benefits of daily physical exercise are more pronounced on days with high rather than low work demands. Results from two experience sampling studies generally support our hypotheses, revealing that daily physical exercise contributes to next-day well-being, both self- and leader-rated in-role job performance and self-rated, but not leader-rated, extrarole OCB, through the sequential mediation of next-morning positive affect and next-day work engagement. Furthermore, these benefits of physical exercise are more evident on days when employees face high overall work demands (Study 1) and in particular on days with high-hindrance demands but on days with low-challenge demands (Study 2).