Diet, Exercise and Hormone Interactions on Skeletal Muscle

The provision of dietary nutrients is a powerful method by which to alter plasma substrate and hormone concentrations, and to impact cell signalling and protein balance positively in skeletal muscle. Growth hormone, insulin-like growth factor I, testosterone, cortisol and insulin are each uniquely affected by dietary nutrients and exercise. This article summarizes some of the work that has been conducted to assess how diet affects these hormones, in particular the exercise-induced hormone response, with an emphasis on skeletal muscle as a target tissue. Clearly, certain combinations of nutrients, such as carbohydrate combined with protein, can be used to alter nutrient and hormone availability to augment skeletal muscle protein balance. There is a need to link acute diet-induced hormonal responses with chronic muscle adaptations to training, and to determine how chronic manipulations in diet affect training adaptations specific to skeletal muscle.