Achieving energy balance at the population level through increases in physical activity

Objectives. We estimated the amount of physical activity required for individuals to expend an additional 418.4 kJ (100 kcal) per day with the goal of achieving energy balance at the population level. Methods. Data on total daily energy expenditures were derived from a random sample of adults residing in Geneva, Switzerland, who completed a self-administered physical activity frequency questionnaire. These data were used to simulate the effects of typical physical activity pyramid recommendations on average population energy expenditures for various activity intensities and rates of population compliance with pyramid recommendations. Results. If an average 418.4 kJ (100 kcal) per day increase in energy expenditures is to be achieved, assuming 100% compliance with physical activity pyramid recommendations, the bottom tier of the pyramid must correspond to everyday activities performed at moderate to high intensity levels (e.g., moderate walking or biking). Expected population gains in energy expenditures would be only 167.4 to 251.0 kJ (40 to 60 kcal) per day at a 50% compliance rate. Conclusions. Achieving population-level energy balance through increasing energy expenditures with physical activity increases alone would require profound structural and environmental changes promoting more active lifestyles.