Research from the University of Texas published in the International Journal of Sport Nutrition and Exercise Metabolism has demonstrated that carbohydrates alone are not enough. Amino acids are also critical for muscle recovery. Amino acids serve as the building blocks our muscles use to repair the damage that occurs with exercise as well as to support muscle growth. In fact, consuming as little as 6 grams of essential amino acids (from animal proteins and soy protein, which contain all nine of the essential amino acids) can aid the recovery process, said Abbot. And one specific amino acid, leucine, has been identified as potentially mediating greater maintenance of muscle mass. Leucine plays a key role in building new muscle protein, and 1 cup of chocolate milk has 778 milligrams of leucine.
The problem is that many people, including athletes, don't need the extra calories. According to Clark, an athlete--or anyone for that matter--can simply have a meal with whole foods that includes lean protein and whole-grain carbohydrates. "There is no rush," Clark said. "It's about muscle recovery; you have time." Also, when you think about it, chocolate milk requires refrigeration--which means it is not so convenient after all.
Finally, Clark said that 8 to 12 ounces of chocolate milk will not be enough for recovery. An athlete working out for two to three hours would need more carbs and protein. In terms of protein, athletes engaging in endurance exercise typically need around 0.55 to 0.64 grams of protein per pound of body weight, while strength-training athletes may need 0.73 to 0.77 grams of protein per pound of body weight.
Those doing recreational or moderate endurance and strength training only need 0.36 to 0.54 grams per pound of body weight. Clark also said that a college athlete training for two to three hours would need approximately 3 to 5 grams of carbohydrates per pound of body weight to completely restore glycogen. While chocolate milk can contribute, it contains only 8 grams of protein and 36 grams of carbohydrates per 8 ounces.
The bottom line: The unique combination of carbohydrates and protein, and the fact that fat-free chocolate milk is also a liquid (as opposed to something like yogurt), make it a contender as a muscle-recovery drink. However, a real meal containing protein and whole-grain carbs would be better. And from a weight-loss perspective, it's best to skip the fat-free chocolate milk and have a plain Greek yogurt (80 calories; 0 g fat; 6 g carbs; 15 g protein for more than 5.3 ounces) with a cut-up banana (1 medium = 105 calories; 0.39 g fat; 27 g carbs; 3 g fiber; 1.29 g protein).
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