After a medical inclusion visit, the participants will realize a maximal aerobic test at the university hospital as well as a body composition analysis, a blood sample will be taken, their resting metabolic rate will be assessed as well as their energy metabolism during a rectangular cycling exercise. Their muscle strength and architecture will be assessed. Their energy intake and eating habits will also be assessed as well as their diet-induced thermogenesis in response to a fixed and an ad libitum meal. Their sleep metabolism will also be assessed using the Dreem technology. Questionnaires will be used to evaluate their daily free living energy intake and accelerometers used to assess their daily physical activity level.~The participants will then perform a 12-week physical activity intervention with 15 of the 30 constitutionally lean one receiving a protein supplementation (randomly assigned). All the measures will be replicated at the end of the intervention as well as 6 weeks after
The main aim of the present study is to compare the effect of a 12-week physical activity program on body weight gain and body composition changes between normal weight and constitutionally lean individuals. The second objective will be to question the potential additional effect of a protein supplementation coupled to the physical training intervention on body wright and body composition in constitutionally lean women.