|
Carbs Do Not Boost Protein Effects |
|
|
|
|
Written by Superhuman
|
|
Thursday, 17 January 2008 |
|
Pre or post-exercise supplements containing amino acids, protein hydrolysates (“predigested” proteins), or whole proteins boost protein synthesis and promote muscle growth and strength. Adding carbohydrates to the supplement might
work even better. A sophisticated Dutch study found that adding carbs had no further benefits than protein hydrolysates alone. They used radioactive tracers to measure the rates of protein synthesis and muscle carbohydrate metabolism. Men lifted weights and then took supplements containing protein hydrolysates and either zero, low levels or high levels of carbohydrates. The protein supplement increased muscle protein synthesis, but adding carbohydrates had no additional effect. However, the high carbohydrate-protein supplement caused greater increases in insulin, which might boost post-exercise glycogen (stored carbohydrate) replenishment. This study showed that including carbs in a post-workout supplement did not further stimulate post-exercise muscle protein synthesis. Other studies found different results. (American Journal Physiology Endocrinology Metabolism, 293: E833–E842, 2007)
|
