Earlier this month I wrote a blog about a study which found that supplementation with protein (whey protein) and the amino acid leucine resulted in increased muscle mass and muscle strength over an 8-week period. I was particularly interested in this because I sometimes recommend whey protein supplementation to individuals looking to maximise muscle gains to be had from resistance exercise.
I came across another study recently that suggests that protein has power to improve body composition in other ways too .
In this study, normal weight women (average age 25) were assessed for a number of parameters including the rate at which the burn fat during exercise, body mass, and body fat.
Over the next 3 months, half the study participants had about 480 calories of their normal diet substituted for a protein rich supplement each day. The other half made the same substitution, but with supplements rich in carbohydrate and fat.
At the end of the study period, all of the women were reassessed.
Compared to the women substituting with carbohydrate and fat, those substituting with protein saw:
- Enhanced fat metabolism during exercise
- Enhanced fat free mass (weight of body from tissue other than fat such as muscle)
- Reduced fat mass
- Reduced body fat percentage
In other words, by replacing some of their usual diet with protein-rich foodstuffs, these women saw improvements in their body composition with (and this is important), no additional exercise. And no conscious restriction of calories either. Sounds like a plan.
1. Soenen S, et al. Protein intake induced an increase in exercise stimulated fat oxidation during stable body weight. Physiol Behav. 2010;101(5):770-4