By Douglas Bolster
PhD, Manager, Sports Nutrition Science, Cadbury Schweppes Americas Beverages


Recently, researchers at McMaster University released a study highlighting the benefits of milk post exercise over a regular sports drink. According to the study, in addition to providing liquid for rehydration and carbohydrates for energy, milk also provides protein which is critical for post exercise muscle recovery. But the science behind protein post-exercise is not new news; athletes have been using protein-based drinks to speed muscle recovery for years. What we are just learning more about, and what many studies fail to recognize, is the benefit of consuming protein during exercise.

Let’s take a closer look at the use of protein during exercise.

During prolonged exercise, the body breaks down muscle to meet energy needs. Carbohydrates and fats are the primary fuels metabolized during endurance exercise, that’s why most athletes consume carbohydrates during exercise in some sort of liquid drink format. However, during prolonged exercise, protein can contribute 5-10% of total energy demands [1, 2] and this contribution can increase under conditions of low carbohydrate stores [3, 4]. Protein's contribution to total energy production during exercise is less than carbohydrates and fat, but don't rule out the impact protein can have during endurance training and performance.

The type of fuel that is used by the muscles for energy during endurance exercise is dependent on numerous factors such as exercise intensity, duration, training status and diet. For example, during low to moderate (<65% VO2 max) intensity, the muscles rely primarily on fat for energy [5]. As exercise intensity increases, there is a shift to an increased reliance on carbohydrates [5]. The use of protein by exercising muscle also increases as exercise intensity increases.

That’s why, as you train or exercise, the body needs a variety of nutrients: water and sodium for rehydration, carbohydrates to replenish muscle fuel stores, and protein to extend endurance, speed muscle recovery and enhance rehydration.

It is crucial for endurance athletes to maintain lean muscle mass during training and competition to maximize performance. A carbohydrate-protein sports drink can aid in maintaining protein balance which helps to maintain muscle mass.


Achieving your Best
Every athlete wants to perform at his/her best. To do this, delaying the onset of fatigue during exercise is a must. Known causes of fatigue during endurance exercise are low carbohydrate stores and/or low blood sugar.

Research has shown that consuming a carbohydrate-protein sports drink during exercise can minimize muscle protein breakdown [6, 7], may aid in supporting muscle protein synthesis [6], and improve protein net balance [6, 7].

And what athlete doesn't want to recover quicker? That's why protein consumed during exercise may help start the rebuilding process of muscles damaged during exercise. But figuring out how much protein to consume is critical.

Take for example the carbohydrate-protein sports drink Accelerade. The right amount of protein found in Accelerade facilitates rehydration by optimizing the absorption of fluid. This level of protein in Accelerade provides an array of functional benefits. It’s an advanced sports drink that has a patent-pending 4:1 carbohydrate to protein ratio, which has been scientifically shown to extend endurance, speed muscle recovery and enhance rehydration.

Milk has a greater ratio of protein to carbohydrate. This ratio is great for recovery but hard to digest during exercise because of the higher amount of protein. Carbohydrate-protein sports drinks such as Accelerade are recommended during exercise or training sessions because it is easy to digest and offers the necessary nutrients to extend endurance, enhance rehydration and speed muscle recovery.

Although more research on the benefits of protein during exercise is forthcoming, Accelerade’s patent-pending formulation with the 4:1 carbohydrate to protein ratio has been shown to extend endurance, speed muscle recovery and enhance rehydration through four independent, scientific studies including peer-reviewed publications in the International Journal of Sport Nutrition and Exercise Metabolism and Medicine & Science in Sports and Exercise

During exercise it is recommend to ingest a fluid replacement beverage approximating 600mL to 1000mL of a carbohydrate-protein based drink for every hour of intense exercise. Ideally, fluid should be consumed frequently in 250 mL quantities and individual needs will vary, depending on size, weight and training intensity.

For more information about Accelerade, visit www.accelerade.ca.


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1. Brooks, G.A. and J. Mercier. J Appl Physiol, 1994. 76(6): p. 2253-61.
2. Dohm, G.L. Exerc Sport Sci Rev, 1986. 14: p. 143-73.
3. Lemon, P.W. and J.P. Mullin. J Appl Physiol, 1980. 48(4): p. 624-9.
4. van Hall, G., et al.. J Physiol, 1996. 494 ( Pt 3): p. 899-905.
5. Romijn, J.A., et al. Am J Physiol, 1993. 265(3 Pt 1): p. E380-91.
6. Koopman, R., et al. Am J Physiol Endocrinol Metab, 2004. 287(4): p. E712-20.
7. Miller, S.L., et al., Int J Sport Nutr Exerc Metab, 2007. In press.