Many athletes assume when training is dragging on, or you feel like you are running on an empty tank during competition, the answer is to reach for an energy drink, suck on sweets or eat a candy bar.
A 2020 study has shown that drinking a sugar-sweetened drink during exercise has no impact on your carbohydrate metabolism. That means you burn up your reserves of muscle and liver glycogen (your body’s stored glucose) at the same rate, regardless of what you are drinking. The sugar content in your drink has no immediate effect on ramping up your carbohydrate reserves.
The chances are that you are dehydrated and need to increase your body’s fluid level, not your carbohydrate intake.
While glycogen storage should last for at least 120 mins, you can start impairing your performance within just 30mins, depending on your rate of fluid loss and the temperature and climate you are exercising in.