Diet high in protein-rich foods with structured sport activity may be useless to lose fat mass and maintain fat-free mass.

Background: The aim of this study was to demonstrate that a normal protein diet along with minimal sports activity can be enough to lose fat mass and maintain muscle mass.

Methods: All participants were prescribed a hypocaloric nutritionally balanced Mediterranean-style diet tailored to the individual for 8 weeks. Body composition and energy expenditure were measured. Sedentary patients (G1) were only recommended to perform minimal aerobic training, while sport subjects (G2) were prescribed structured physical activity and higher calorie and protein contents in the diet.

Results: There were no significant differences between the two groups for any of the measured parameters.

Conclusions: The models of lifestyle changes that are currently circulating were for the most part ineffective. It does not appear to be necessary to increase the protein content of the diet above that recommended by guidelines in order to lose weight. Even prescribing specific physical activity is not necessary to maintain muscle mass.