Around competitionsThe key to sporting success is to start the event with maximum glycogen reserves and optimum hydration.
- During the 2 or 3 days before the competition, the diet must be rich in medium GI carbohydrates (eg. "Pasta party"). Eat as much pasta (al dente!) and rice as possible, while still maintaining the balance of usual components of a meal : main course (meat or equivalent + pasta or rice), dairy product (e.g. yogurt, custard), cake type dessert, bread, water.
- The last meal (2 to 3 hours before the event) must be low in lipids and dietary fibre, and rich in carbohydrates with medium to high GI foods.
- Intake while waiting (2 h to 30 min before the event) consists of drinking water every 30 minutes, maybe accompanied by biscuits, cereal bars, a yogurt and/or a very ripe fruit.
- 30 to 15 minutes before the start of the event, have 250 to 300 ml of an isotonic drink (but this time without food) that includes 5 to 8 g of simple carbohydrates per 100 ml.
During competitionFood varies depending on the sport
For exercise lasting 1 to 3 hours, you should drink an isotonic drink with sweetened exercise foods. For more than 3h exercise, you should drink an isotonic drink accompagnied by some food (low in lipids) that provides high GI carbohydrates (eg. fruit paste jelly) and low GI carbohydrates (eg. cereal bars). During the exercise, it is important to drink regularly in small quantities by repeated drinks (150 to300 ml per drink, equivalent to at least 600 ml/h). *, **, ***
The drinks must be at about 15°C; they must not be iced so as not to disrupt temperature regulation.
During very prolonged exercise (3 to 4 h), the quantities of sweat lost can reach 7 to 8 litres. The risk is therefore of hyponatraemia (lowering of blood sodium concentration), expressed as muscle cramps, behavioural problems, even a loss of consciousness. It is therefore important to take drinks that provide sodium during and after long lasting exercise.
* Bigard AX, Guezennec CY, L'hydratation au cours des exercices de longue duréee [Hydration during long lasting exercise], Cahiers de Nutrition et de Diététique [Reports on Nutrition and Diet], 1996, 31, 149-57.
** Koulmann N, Banzet S, Bigard AX, L'activité physique à la chaleur: de la physiologie aux recommandations d'apport hydrique [Physical activity in the heat: from physiology to water intake recommendations], Med Trop [Tropical Medicine], 2004, 63, 617-26.
*** Koulmann N, Bigard AX, Hydratation et sports, In Nutrition du Sportif [Hydration and sports, in Nutrition of the Sportsman], Bigard AX, Guezennec CY, " Sport " Collection, Masson publishers, Paris, 2003, 235 pages.