Figure 1. Model of human energy expenditure components (adapted from (46)). Exercise-related physical activity is comparable to exercise-related activity thermogenesis (EAT), while spontaneous physical activity is comparable to non-exercise activity thermogenesis (NEAT); for further explanations see text. Note that parts of spontaneous physical activity are beyond voluntary control, also called “fidgeting.” Arrows symbolize the multiple and varying impacts of individual factors, genetic background, and environment.