Consuming a protein or protein and carbohydrate shake after your workout has many benefits such as
promoting protein synthesis and enhancing glycogen resynthesis. This is due in part to the anabolic hormonal
response, such as an increase in insulin, created by the protein and carbohydrate. However, contrary to what
you might think, the anabolic hormone testosterone in the blood is actually decreased when food is consumed after
resistance exercise. The reason for this decrease is not known, but it could be due to decreased synthesis or
increased uptake. If greater uptake in muscle is the explanation, this is actually a good response because it
means more testosterone is acting on muscle to stimulate growth. In this study, subjects who consumed a protein
and carbohydrate shake after a bout of resistance exercise experienced a greater reduction in testosterone as
expected, but this was also associated with a greater increase in the receptor that binds testosterone on muscle.
So rest assured you should definitely consume some protein and carbohydrate after workouts because it stimulates
anabolic hormone receptors at the target tissues, muscle that is.
Kraemer WJ, et al. Effects of L-carnitine-L-tartrate supplementation on testosterone and muscle androgen receptor
content after resistance exercise.
Federation of American Societies for Experimental Biology, Washington D.C., April,
2004. Abstract #851.8.