“The amount of carbohydrates that you take on during the cycle and run can often decide the result of the race.” – Sebastian Kienle
In order to successfully complete a multi-day stage cycling race like the Tour de France, specific training and also the genetic prerequisites are very important. In addition to these factors, the right carbohydrate and fluid strategy is probably one of the most important factors for a successful performance in the race.
Even with the right genetic make-up and best training program, making sure you have the right carbohydrate intake and hydration strategy is crucial for successful race performance. The body stores energy from carbohydrate in the form of glycogen in muscles and the liver. Muscle glycogen is a readily available energy source for exercising muscles. Liver glycogen is essential in helping maintain blood sugar (glucose) levels, as ensuring a constant supply of glucose prevents effects associated with hypoglycaemia (low blood sugar level) i.e. shakiness, anxiety and reduced concentration. Once these glycogen stores become depleted, exercise at maximal intensities cannot be maintained. That’s why the body must be supplied periodically with carbohydrates in the right form and at sufficient rates during a prolonged intense endurance session.
“How” does carbohydrate intake during exercise improve performance?
- The function as an energy supplier by maintaining blood glucose concentration and high rates of carbohydrate oxidation when glycogen levels in muscles and liver are low.
The impact on the brain: for exercise sessions lasting less than an hour, the body’s glycogen stores are not a performance-limiting factor. However, recent research has shown that carbohydrates can improve performance even in those sessions – even without actual ingestion. Simply rinsing the mouth for a few seconds with a beverage containing carbohydrates activates specific receptors in the oral mucous membranes. This stimulates the central nervous system in the brain, which can cause a performance-enhancing effect.
Recommendations for the optimum carbohydrate intake quantity during competition
Conclusion: The optimal amount of carbohydrate intake during competition highly depends on the duration and intensity of the exercise, but must also be tailored according to the athlete’s individual tolerance. Train and practise your carbohydrate strategy during training and never try out something new in the competition!
© Corinne Mäder Reinhard, Senior EU Sports Nutrition Manager PowerBar. International Olympic Committee post-graduate Diploma in Sports Nutrition
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