Before the sports event, it is important to fill up your carbohydrate store, hydrate properly, and take in minerals. To do this, drink 150-300 ml of fluid about 20 minutes before starting, for example. If you want to settle your stomach or fill up your carbohydrate store, you can have a carbohydrate-rich snack such as a carbohydrate bar (an Energy Bar for instance) just before you start. This way the carbohydrate store remains full for longer.