Bearded Beast of Duloc
Casey Butt on Amino Acids
Looking at glycogen resynthesis first...
Ivy, J.L. "Early postexercise muscle glycogen recovery is enhanced with a carbohydrate-protein supplement."
"There were no significant differences in the plasma insulin responses among treatments, although plasma glucose was significantly lower during the carbohydrate-protein treatment. These results suggest that a carbohydrate-protein supplement is more effective for the rapid replenishment of muscle glycogen after exercise than a carbohydrate supplement of equal carbohydrate or caloric content."
Subjects cycled for 2.5 ± 0.1 hour to glycogen depletion. Conclusion: Essentially, it's better to take protein and carbs together than carbs alone.
Zawadzki, K.M. "Carbohydrate-protein complex increases the rate of muscle glycogen storage after exercise."
"The rate of muscle glycogen storage during the carbohydrate-protein treatment [35.5 +/- 3.3 (SE) mumol.g protein-1.h-1] was significantly faster than during the carbohydrate treatment (25.6 +/- 2.3 mumol.g protein-1.h-1), which was significantly faster than during the protein treatment (7.6 +/- 1.4 mumol.g protein-1.h-1). The results suggest that postexercise muscle glycogen storage can be enhanced with a carbohydrate-protein supplement as a result of the interaction of carbohydrate and protein on insulin secretion."
Male subjects cycled for three sessions of 2 hours to deplete glycogen stores. Again, it's better to take protein and carbs together than carbs alone.
Jentjens, R.L. "Addition of protein and amino acids to carbohydrates does not enhance postexercise muscle glycogen synthesis."
"No difference was found in plasma glucose or in rate of muscle glycogen synthesis between the carbohydrate and the carbohydrate + protein-amino acid mixture trials. Although coingestion of a protein amino acid mixture in combination with a large carbohydrate intake (1.2 g · kg1 · h1) increases insulin levels, this does not result in increased muscle glycogen synthesis.
Study used male cyclists exercising to "glycogen depletion". With regards to glycogen synthesis, protein and aminos have no additional effect over just carbs alone.
Roy, B.D. "Influence of differing macronutrient intakes on muscle glycogen resynthesis after resistance exercise."
"These results demonstrated that a bout of resistance exercise resulted in a significant decrease in muscle glycogen and that consumption of an isoenergetic carbohydrate or carbohydrate/protein/fat formula drink resulted in similar rates of muscle glycogen resynthesis after resistance exercise. This suggests that total energy content and carbohydrate content are important in the resynthesis of muscle glycogen."
Study used males performing a full-body resistance workout. Carbs and carbs + protein + fat had similar glycogen resynthesis rates given both treatments contained the same total calories.
Burke, L.M. "Effect of coingestion of fat and protein with carbohydrate feedings on muscle glycogen storage."
"Dietary guidelines for achieving optimal muscle glycogen storage after prolonged exercise have been given in terms of absolute carbohydrate (CHO) intake (8-10 g.kg-1.day-1). However, it is of further interest to determine whether the addition of fat and protein to carbohydrate feedings affects muscle glycogen storage. Eight well-trained triathletes [23.1 +/- 2.0 (SE) yr; 74.0 +/- 3.4 kg; peak O2 consumption = 4.7 +/- 0.4 l/min] undertook an exercise trial (2 h at 75% peak O2 consumption, followed by four 30-s sprints) on three occasions, each 1 wk apart. For 24 h after each trial, the subjects rested and were assigned to the following diets in randomized order: control (C) diet (high glycemic index CHO foods; CHO = 7 g.kg-1.day-1), added fat and protein (FP) diet (C diet + 1.6 g.kg-1.day-1 fat + 1.2 g.kg-1.day-1 protein), and matched-energy diet [C diet + 4.8 g.kg-1.day-1 additional CHO (Polycose) to match the additional energy in the FP diet]. Meals were eaten at t = 0, 4, 8, and 21 h of recovery. The total postprandial incremental plasma glucose area was significantly reduced after the FP diet (P < 0.05). Serum free fatty acid and plasma triglyceride responses were significantly elevated during the FP trial (P < 0.05). There were no differences between trials in muscle glycogen storage over 24 h (C, 85.8 +/- 2.7 mmol/kg wet wt; FP, 80.5 +/- 8.2 mmol/kg wet wt; matched-energy, 87.9 +/- 7.0 mmol/kg wet wt)."
Subjects experienced triathletes. As long as carbs are sufficient, adding protein or fats to postworkout meals has no effect on overall glycogen resynthesis rates.
Conclusion: It might be better to combine carbs + protein or even carbs + protein + fat after training, or carbs alone may replenish glycogen just as quickly. In either case, the addition of protein and fat won't hurt and may very well help.
Now looking at protein synthesis...
Koopman, R. "Combined ingestion of protein and free leucine with carbohydrate increases postexercise muscle protein synthesis in vivo in male subjects."
"We conclude that coingestion of protein and leucine stimulates muscle protein synthesis and optimizes whole body protein balance compared with the intake of carbohydrate only."
Male subjects performed 45 mins of resistance exercise. Conclusion: Protein and carbs after training results in higher protein synthesis rates than carbs alone.
Tipton, K.D. "Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise."
"These results indicate that the response of net muscle protein synthesis to consumption of an essential amino acid-carbohydrate supplement solution immediately before resistance exercise is greater than that when the solution is consumed after exercise, primarily because of an increase in muscle protein synthesis as a result of increased delivery of amino acids..."
Three male and three female subjects performed 10 sets of 8 reps of leg presses at 80% of 1RM. It's better to take amino acids+carbs before training that it is to take them after. But be careful drawing conclusions here because the study compared nutrient ingestion before training vs. that of training in a fasted state.
Tipton, K.D. "Stimulation of net muscle protein synthesis by whey protein ingestion before and after exercise."
"Previously, we demonstrated that net amino acid uptake was greater when free essential amino acids plus carbohydrates were ingested before resistance exercise rather than following exercise. However, it is unclear if ingestion of whole proteins before exercise would stimulate a superior response compared with following exercise. This study was designed to examine the response of muscle protein balance to ingestion of whey proteins both before and following resistance exercise. ...Amino acid uptake was not significantly different between PRE and POST when calculated from the beginning of exercise (67 ± 22 and 27 ± 10 for PRE and POST, respectively) or from the ingestion of each drink (60 ± 17 and 63 ± 15 for PRE and POST, respectively). Thus the response of net muscle protein balance to timing of intact protein ingestion does not respond as does that of the combination of free amino acids and carbohydrate."
Seventeen males and females performed 10 sets of 8 reps of leg extensions at 80% of 1RM. If you're ingesting whole protein alone then it doesn't seem to matter if you take it before or after training. If you're taking a free amino acid + carb mixture it's best to take it before. Again subjects were fasted to start but this time took either whey protein alone, before or after training.
Bird, S.P. "Independent and combined effects of liquid carbohydrate/essential amino acid ingestion on hormonal and muscular adaptations following resistance training in untrained men."
"These data indicate that liquid carbohydrate + essential amino acids ingestion enhances muscle anabolism following resistance training to a greater extent than either liquid carbohydrate or essential amino acids consumed independently. The synergistic effect of liquid carbohydrate + essential amino acids ingestion maximises the anabolic response presumably by attenuating the post-exercise rise in protein degradation."
32 young adult males (beginners) trained twice per week for 12 weeks with blood samples being taken immediately before and after exercise at weeks 0, 4, 8 and 12. It's better to take protein and carbs together than either alone.
Borsheim, E. "Effect of an amino acid, protein, and carbohydrate mixture on net muscle protein balance after resistance exercise."
"We conclude that after resistance exercise, a mixture of whey protein, amino acids, and carbohydrates stimulated muscle protein synthesis to a greater extent than isoenergetic carbohydrates alone. Further, compared to previously reported findings, the addition of protein to an amino acid + carbohydrates mixture seems to extend the anabolic effect."
Eight subjects performed two separate bouts of resistance training. After training, a mixture of protein plus carbs is better than carbs alone.
Finally, a conclusion with regards to both glycogen replenishment and protein synthesis...
Ivy, J.L. "Dietary strategies to promote glycogen synthesis after exercise."
"It has been observed that muscle glycogen synthesis is twice as rapid if carbohydrate is consumed immediately after exercise as opposed to waiting several hours, and that a rapid rate of synthesis can be maintained if carbohydrate is consumed on a regular basis. For example, supplementing at 30-min intervals at a rate of 1.2 to 1.5 g carbohydrate x kg(-1) body wt x h(-1) appears to maximize synthesis for a period of 4- to 5-h post exercise. If a lighter carbohydrate supplement is desired, however, glycogen synthesis can be enhanced with the addition of protein and certain ami no acids. Furthermore, the combination of carbohydrate and protein has the added benefit of stimulating amino acid transport, protein synthesis and muscle tissue repair. Research suggests that aerobic performance following recovery is related to the degree of muscle glycogen replenishment."
All in all, the research suggests that for both performance and muscle growth it's best to consume protein plus carbs both before and after exercise, the addition of fats into the mix seems to have no effect on glycogen replenishment. Furthermore, if you're eating a normally timed, adequate diet then some of these conclusions may be altered because assuming you don't train before breakfast your bloodstream would have protein, glucose and fats present anyway (in other words, a non-fasted state). So, it looks like the research supports Joe's assertion about 3 squares a day, with the exception that it does appear important to take in a balanced meal with 1 hr following training - altough that could just as easily be your dinner or supper as any bodybuilding supplement. Incidentally, there was a recent study comparing the ingestion of milk postworkout to a popular bodybuilding "recovery" supplement, and the milk equalled or outperformed the supplement (after all, milk has roughly a 60/40 carbs to protein split which is supported by the research).
So, as far as the body of research is concerned: Don't train in a fasted state if you're trying to get bigger/stronger; ingest some protein and carbs after training (perhaps some fats too); and there is no support to conclude that supplements outperform regular food.
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