Carbohydrate is the most important energy substrate under competition when the intensity is high, > 82 % of maximal heart rate. This is because glucose that stored in liver and muscle as glycogen, generates faster energy for the working muscle by the conversion of glucose to ATP than fat. Glycogen stores in liver are about 80 – 110 grams and in muscle 300-600 g.
Depending on the glycogen store before race, duration and intensity, the storages will emptied after 1-2 hours if you not get energy during long competitions. In a performance perspective, it is not expedient, as you will not be able to maintain the intensity and speed. Your performance will be reduced. This is because your body starts to use fat as energy.
Remember to give your body enough fluids during the competition. You lose fluid through evaporation and sweat, and the loss increases during activity. How much fluid you need is very individual. Thus, you should calculate your own sweat rate.
When to eat and drink?
You don’t need any energy intake during competitions lasting up to an hour. If the competition last longer, for example as the races in Visma Ski Classic, you will need energy. If the race last 1-3 hours, add 30-60 g carbohydrate every hour. From 2 to >3 hours you will need 45-90 g, with a mix of both glucose and fructose. You have to determine what your body can tolerate, as problems with the gut can arise when consuming large amounts of carbohydrates. Remember to prepare the body. Example of energy is sports drinks, energy bars, gel, cola, banana and bread with honey or jam.
30-60 carbohydrates equals:
- 5.10 dl sports drink
- 2-3 ripe bananas
- 1-1.5 dl raisins
- 2-3 slices of bread with honey
- 1-2 sports bars
You need to start drinking before you get thirsty, otherwise it would be too late and the performance will be reduced. It is optimal to drink every 15 – 25 minute, and 1.5 – 3 dl on each drinking station. This amounts to 4-8 dl per hour. Sports drink is preferred to get a good mix of fluid and electrolytes (minerals), so that the body absorbs the liquid and avoids electrolyte disturbances.
Long time between drink stations?
It is not certain that all drinking stations are set up exactly according to your needs. Usually it goes a little longer than 30 minutes prior to ingest some fluid. Therefore, you should find out where it is drink stations and then devise a plan. It is important to take the time to ingest enough drink when you have the opportunity. The time lost will be greater if you become dehydrated than if you are standing some seconds longer to get two cups of drinks. If you want, you can also go with a little bag/drink belt to control you’re drinking routines hundred percent. If possible, have you fluid break in the slopes to not lose too much speed. This also applies to intake of gels, bars and so forth.
Do you want to know more about nutrition? Read the blog post about what you should eat and drink the time before ski races. For more news and updates about Visma Ski Classics, visit our website.