Apart from the glucose that originates from the muscle cell glycogen and liver glycogen, isotonic drinks should be another important source of energy during endurance competitions of over one hour. These drinks contain not only carbohydrates in a fluid form, but also electrolytes, which the body loses upon sweating and which therefore have to be replenished. The ideal amount of carbohydrates in these drinks is 6-8%. Less than that is insufficient, while in a higher concentration they are absorbed more slowly, which can lead to stomach trouble. By means of training and participating in competitions of little importance, each athlete should experiment with these drinks and find the one that makes him tick. In my case, for example, during triathlons and half marathons, it works to drink half a glass of isotonic drinks every 20 minutes and one glass 15-20 minutes before the beginning of the competition.
Moreover, as I already mentioned, during long-distance com-petitions, the human body does not only use glycogen, but also fat and proteins for the production of energy; albeit in smaller amounts, especially towards the end of the race. Our bodies prefer the energy production from carbohydrates, since it is more efficient than that from fat (which is stored in our bodies more plentifully than carbohydrates). Apart from storing more glycogen, an endurance athlete’s body should be able to mobilize and utilize fat reserves more efficiently. In order to train your body to burn fat, you should add a weekly long-duration and low-intensity run (over 1:30 h) to your training schedule. This kind of training makes the energy production process more reliant on fat than on carbohydrates.
Another important factor is: as a rule, endurance athletes should have determined their tactic and the speed at which they will per-form during each race, based on their training experience. They should stick to their plan, and under no circumstances should they get carried away by faster athletes or a sense of overconfidence and increase their speed. Generally, you pay a big price for that kind of cockiness during a race, since he glycogen reserve is exhausted much faster that way. It is better to finish a race according to plan; there will be many other competitions in the future where you can go faster, if you plan it.
Endurance athletes have to make sure that their glycogen levels are at maximum levels on the day of he race. In order to do so, they should not tap into these reserves
during the last three days before the competition by training for hours. Their nutrition should have an increased amount of carbohydrates.