Volunteers at the Beijing Winter Olympic Games experienced a transition from work to rest, which provided a natural control setting to observe how people adapted from work to rest in restricted environment. This study examined changes in their physical and mental health over a five-week period, as well as individual differences in trajectories of change. Participants completed personality measures before the start of their volunteer work and reported their weekly physical and psychological health over the next five weeks. Piecewise growth models detected little change in physical and mental health during work or during rest, but a significant decline during the transition from work to rest. Specifically, the work period was associated with higher levels of positive affect, anxiety, covid-stress and overall food consumption, while the rest period was linked to higher levels of depression and general stress. Additionally, although the rest period had longer sleep duration, sleep quality was lower compared to the work period. Conscientiousness and extroversion acted as protect factors. Drastic changes in physical and psychological health indicated big differences between work and rest, and emphasized the importance of transition period. Future research should further explore the psychological mechanism in the changing schedule and environment.