Wanna know whether to have your shake pre or post workout? I wouldn’t argue with these guys.
E197 K. D. Trpton et al. ‘Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise’ American Journal of Physiology 2001; 281: - E 206
To determine whether ingesting a combination of AA and CHO before exercise is more effective in stimulating net muscle protein synthesis than ingesting the mixture after exercise
DESIGN & METHODS:
Protein turnover was compared following resistance exercise and ingestion of CHO and AA solution either immediately prior to or immediately following the exercise bout in healthy young participants
500 ml drink with 35 g of CHO and 6 g of essential AA [size of a small snack]
Resistance exercise consisted of leg press (10 sets of 10) and knee extension (8 sets of 8) exercises at 80% 1 - RM.
Femoral arterial and venous samples of phenylalanine were obtained to determine protein turnover via rates of appearance (Ra) and disappearance (Rd).
“Ra of Phenylalanine [amino acid, in the blood] did not change significantly from resting levels during or after exercise in either the PRE or POST”
“Rd [from blood, into muscle] increased from rest in the hour immediately after EAC [Essential Amino Acid-Carbohydrate supplement] consumption by 216% during PRE [consumption] (during exercise) and by 60% during POST [consumption] (1st hour after exercise). PRE [consumption] Rd was significantly greater than POST [consumption] Rd during exercise and in the first hour after exercise.”
“During PRE, NB [net balance, ie protien intake into muscle] changed from negative at rest to positive values during exercise and the 1st hour postexercise. During POST, NB was negative at rest AND during exercise but increased to positive values after exercise when the EAC drink was consumed. NB during POST immediately returned to zero in the 2nd hour after exercise.”
“NB was significantly greater during exercise AND in the 1st hour after exercise in the PRE trial than in the POST trial.”