Is there a need for a special diet post exercise

After moderate-intensity exercise with glycogen depletion, muscle glycogen content (like liver glycogen) is regenerated to a normal level in 2-3 days on a mixed diet and in approximately 24 h on a carbohydrate-rich diet. Provided that the emptying of the muscle glycogen has been extensive and the following intake of carbohydrate is large, muscle glycogen will be regenerated to higher levels than before exercise (supercompensation).

The type of carbohydrate probably plays its most important role in the postexercise diet. Thus, one study showed that the glycogen storage rate after glycogen-depleting exercise (1.5-2 h at 75% of V°2 max) was higher 6 h after intake of high GI carbohydrates compared to low GI carbohydrates [56]. Faster glycogen resynthesis with glucose compared to fructose has also been found during the hours after exercise. After 20 h, however, no difference between the glycogen resynthesis was found after high or low GI carbohydrates. However, another study showed that after 24 h a high GI diet increased muscle glycogen stores 50% more than a low GI diet [57]. If exercise takes place once or twice daily, it is therefore advisable to choose high GI carbohydrates after training. With exercise only once a day or less and a recovery period of more than 24 h, the type of carbohydrate does not seem to be important for the training outcome, but this has not yet been completely clarified.

A problem often encountered by athletes is a decreased appetite for up to 2-3 h after heavy exercise [58]. To overcome this problem, a carbohydrate-containing drink is advisable. In this way both fluid balance and muscle glycogen can be rapidly restored. It has not yet been clarified, though, if additional protein intake — resulting in a positive nitrogen balance — can be advantageous with respect to muscle building and performance.

For most athletes, a sufficient protein intake will not be a problem. This implies, however, that the athletes are in energy balance and consume varied meals containing all the essential amino acids. In types of sport with frequent periods of energy deficiency during training (running, gymnastics, athletics, ballet) as well as for vegetarians (especially vegans), the diet may be low in proteins and insufficient with respect to essential amino acids [59]. Examples of complete protein combinations are: beans + rice, peas + corn, pulses + bread, cereals + milk or eggs, and potatoes + eggs or milk. One should also bear in mind that the bioavail-ability of vegetable protein from a fiber-rich diet is estimated to be i0% lower than the bioavailability of animal protein.

Studies on the dietary intake of Kenyan runners by Christensen and collaborators [60] were able to show, however, that the high carbohydrate and low fat intake, which was similar to that reported in endurance runners from other low-income countries, was suffi cient to cover energy as well as protein intake, including the need of essential amino acids, despite the diet being based on a small range of mainly vegetable food items.

Was this article helpful?

0 0
Osteoarthritis

Osteoarthritis

Thank you for deciding to learn more about the disorder, Osteoarthritis. Inside these pages, you will learn what it is, who is most at risk for developing it, what causes it, and some treatment plans to help those that do have it feel better. While there is no definitive “cure” for Osteoarthritis, there are ways in which individuals can improve their quality of life and change the discomfort level to one that can be tolerated on a daily basis.

Get My Free Ebook


Post a comment