Research published in the Journal of Amino Acids that drinking a combined carbohydrate drink with essential amino acids (EAA) after high-intensity exercise increased IGF-1 levels. The researchers had subjects perform high-intensity exercise, and subjects were assigned to receive either a carbohydrate drink (dosage of .85 g/kg of lean body mass) or a carb-EAA supplement (dosage of .5g/ kg of lean body mass for carbs and .35g/kg of lean body mass for EAAs). At the end of the study, there were increases in GH across the entire group after high-intensity exercise but free IGF-I in the carb/EAA group only. These results indicate that slamming a high-quality carb/EAA drink immediately after exercise can increase IGF.
If that’s not enough, it seems that consuming carbs with EAA can also reduce muscle damage so you can recuperate faster. Thirty-four male subjects completed three sets of eight reps at their 8RM in the following exercises: high pull, leg curl, standing overhead press, leg extension, lat pulldown, leg press, and bench press. Subjects consumed either a carb-EAA sports drink or placebo 30 minutes prior to exercise, immediately before exercise, halfway through the workout, and immediately afterward. At the end of the study, cortisol responses were significantly elevated in the placebo group compared to the carb-EAA group at 24 hours post-exercise. And myoglobin and creatine kinase were significantly elevated in the placebo group compared to the carb-EAA group. There was no difference in exercise performance, but the carb and protein group had better markers for muscle recuperation, suggesting the use of a carb-EAA supplement during training reduces muscle damage and soreness.
-Foster, E., Fisher, G., Sartin, J., Elsasser, T., Wu, G., Cowarn, W., Pascoe, D. Acute Regulation of IGF-1 by Alterations in Post-Exercise Macronutrients. Amino Acids. February 2011. 40(2).