Purpose of review: To discuss the potential importance of spontaneous physical activity in regulating body weight and outline possible reasons for the large interindividual variance in spontaneous physical activity.
Recent findings: Spontaneous physical activity is highly variable among people, with some having high levels and some low, and can contribute significantly to interindividual differences in total daily energy expenditure. Cross-sectionally, spontaneous physical activity is inversely related to body weight; however, more importantly, spontaneous physical activity is inversely associated with weight gain in prospective studies, and experimental weight perturbations do not appear to change spontaneous physical activity behavior. Spontaneous physical activity is a familial trait and is biologically influenced, although the environment exerts a significant impact.
Summary: Although spontaneous physical activity is a biologically driven behavior, interventions to increase nonexercise activity within the workplace and school hold promise in increasing daily energy expenditure for the average sedentary American. However, many large-scale efforts will need to take place within our sedentary-promoting environment to encourage more daily spontaneous physical activity-related activity.