Bidirectional relationship of stress and affect with physical activity and healthy eating

Objectives. Physical activity and healthy eating seem to be protective against experiencing stress and negative emotions as well as increase positive affect. At the same time, previous studies showed that people reduce salutogenic behaviours such as physical activity and healthy eating in the face of stress and negative affect while increasing such behaviours in the context of positive emotions. Due to daily fluctuations of these behaviours, the present study examined these relationships in daily life using ecological momentary assessment (EMA). 

Design and Methods. Fifty-one university students responded to six daily prompts during seven days via smartphone-based EMA. Items examined stress, emotional experience, physical activity duration and healthy eating. 

Results. Higher stress and negative affect, as well as lower positive affect, were related to a reduction in subsequent physical activity. Higher physical activity levels, in turn, were associated with less subsequent stress and negative affect, as well as more positive affect. No such effects for stress and affect on healthy eating or vice versa were found. 

Conclusions. Engaging in physical activity is related to better mood and less stress/negative affect over the next several hours in daily life. Prevention efforts therefore may benefit by focusing on promoting physical activity, particularly when stress/negative affect are high to ‘break the cycle’ of inactivity, stress, and negative affect. Potential effects of healthy eating might be more subtle and characterized by interindividual differences or state effects.