if you want to get complicated heres some more stuff that adds on to both of ours Muscle tissue will grow in the presence of a number of factors, including exercise, hormones (growth hormone, insulin, testosterone and thyroid) and nutrients. Nutrition science has advanced to the point where athletes who supplement with free form amino acids can get IAAs, high in BCAA content, to the muscles much more effectively.
The key is the window of opportunity that occurs immediately after exercise, when the muscle is especially receptive to nutrients and the blood flow to the exercised muscles remains high. The solution to optimizing recovery and growth in this case could include eating a small meal composed of protein with both simple and complex carbohydrates.
This isn't the current high tech approach, however. For one, if you trained hard, chances are - even if a convenient and light, nutritious meal was readily available - you wouldn't feel like eating. More important, a high protein meal won't put significant levels of amino acids into your bloodstream until a couple of hours after you eat it, especially if blood flow to the gastrointestinal tract has been diminished by a hard training session. The bottom line: Even if you eat the right foods soon after training, the nutrients will arrive at the muscle too late to take full advantage of the window of opportunity.
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