Most athletes know of the importance of eating before exercise, however, what and when you eat after exercise can be just as important. While the pre-exercise meal can ensure that adequate glycogen stores are available for optimal performance (glycogen is the the source of energy most often used for exercise), the post-exercise meal is critical to recovery and improves your ability to train consistently.
Hydration After Exercise
The first nutritional priority after exercise is to replace any fluid lost during exercise. A recent study, published in the journal Medicine & Science in Sports & Exercise, reports that athletes who drank chocolate milk after an intense bout of exercise were able to workout longer and with more power during a second workout compared to athletes who drank commercial sports beverages.
The researchers of the study indicate that chocolate milk is a strong alternative to other commercial sports drinks in helping athletes recover from strenuous, energy-depleting exercise. Researcher Joel M. Stager, PhD, professor of kinesiology at Indiana University states that "Chocolate milk contains an optimal carbohydrate to protein ratio, which is critical for helping refuel tired muscles after strenuous exercise and can enable athletes to exercise at a high intensity during subsequent workouts."
Stager and colleagues had nine cyclists bike until their muscles were depleted of energy, rest four hours, then bike again until exhaustion, three separate times. During the rest period, the cyclists drank one of three beverages:
- low-fat chocolate milk
- a traditional fluid replacement sports drink
- carbohydrate replacement sports drink
During the second round of exercise, the researchers found that cyclists who drank chocolate milk during the rest period were able to bike nearly twice as long before reaching exhaustion than those who consumed the carbohydrate replacement drink, and as long as those who consumed the fluid replacement drink.
Researchers theorize that the combination of carbohydrates and protein found in chocolate milk is what helped enhance the cyclists' performance and suggest that flavored milk may be an optimal beverage for refueling muscles after exercise. The researchers also note that chocolate milk is a great-tasting and cost-effective alternative to many sports drinks.
In addition to its ideal combination of carbohydrates and protein, flavored milk contains seven other essential nutrients that are important for an athlete's health - including bone-building calcium. No other sports drink contains the nutrient package found in flavored milk.
This study suggests, as well as many others before it, that a combination of carbohydrate and protein is more beneficial to athletes than just carbohydrate alone in the post-workout meal or supplement. This study takes it one step further by identifying a food product - chocolate milk - that is easy to get, inexpensive, and tastes great.
Eating After Exercise
It is also important to consume carbohydrate within 15 minutes post-exercise to help restore glycogen. Research has shown that eating 100-200 grams of carbohydrate within two hours of endurance exercise is essential to building adequate glycogen stores for continued training. Waiting longer than two hours to eat results in 50 percent less glycogen stored in the muscle. The reason for this is that carbohydrate consumption stimulates insulin production, which aids the production of muscle glycogen. However, the effect of carbohydrate on glycogen storage reaches a plateau.
Carbohydrate Plus Protein Speeds Recovery
Research shows that combining protein with carbohydrate in the two hours after exercise nearly doubles the insulin response, which results in more stored glycogen. The optimal carbohydrate to protein ratio for this effect is 4:1 (four grams of carbohydrate for every one gram of protein). Eating more protein than that, however, has a negative impact because it slows rehydration and glycogen replenishment.
One study found that athletes who refueled with carbohydrate and protein had 100 percent greater muscle glycogen stores than those who only ate carbohydrate. Insulin was also highest in those who consumed a carbohydrate and protein drink.
Protein Needs After Exercise
Consuming protein has other important uses after exercise. Protein provides the amino acids necessary to rebuild muscle tissue that is damaged during intense, prolonged exercise. It can also increase the absorption of water from the intestines and improve muscle hydration. The amino acids in protein can also stimulate the immune system, making you more resistant to colds and other infections.
Sources
- Karp, Jason R.; Johnston, Jeanne D.; Tecklenburg, Sandy; Mickleborough, Tim; Fly, Alyce; Stager, Joel M (2004). The Efficacy of Chocolate Milk as a Recovery Aid. Medicine & Science in Sports & Exercise. 36(5) Supplement:S126.
- Betts JA, et al. Effects of recovery beverages on glycogen restoration and endurance exercise performance Williams MB, et al. Effects of recovery beverages on glycogen restoration and endurance exercise performance. J Strength Cond Res. 2003 Feb;17(1):12-9.
- Ivy JL, Goforth HW Jr, Damon BM, McCauley TR, Parsons EC, Price TB. Early postexercise muscle glycogen recovery is enhanced with a carbohydrate-protein supplement. J Appl Physiol. 2002 Oct;93(4):1337-44.
- Zawadzki KM, Yaspelkis BB 3rd, Ivy JL. Carbohydrate-protein complex increases the rate of muscle glycogen storage after exercise. J Appl Physiol. 1992 May;72(5):1854-9.
- Res, P., Ding, Z., Witzman, M.O., Sprague, R.C. and J. L. Ivy. The effect of carbohydrate-protein supplementation on endurance performance during exercise of varying intensity. International Journal of Sports Nutrition and Exercise Metabolism.
- Levenhagen DK, Carr C, Carlson MG, Maron DJ, Borel MJ, Flakoll PJ. Post exercise protein intake enhances whole-body and leg protein accretion in human. Medicine and Science in Sports & Exercise. 2002 May; 34(5): 828-37.
- Miller SL, Tipton KD, Chinkes DL, Wolf SE, Wolfe RR.Independent and combined effects of amino acids and glucose after resistance exercise. Medicine & Science in Sports & Exercise. 2003 March; 35(3):449-55.