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Glucose - a super fuel

Glucose - a super fuel

Glucose - a super fuel

Glucose is a fuel. It enables us to contract our muscles, from the calves of a marathon runner to your index finger when you click your mouse. Find out why.

During and before exercise, and to ensure we don’t “break down” in the meantime, our body stores energy from carbohydrates in the form of glycogen (elongated chains of glucose) in the liver and muscles.

Before, during and after exercise

For athletes, like everyone else, a meal rich in carbohydrates with a low glycaemic index (“al dente” pasta, starchy food, etc.) consumed the previous day or up to six hours before exercise increases thebody’s glycogen levels.

During muscular exercise, you’re advised to consume food or drinks rich in carbohydrates with a moderate to high glycaemic index (dried fruit, bananas, sugar lumps, etc.) Immediately after the exercise, carbohydrates enable us to replenish our stocks!

Managing your energy balance

Put simply, our weight balance, and therefore our shape, is the right balance between food intake and energy expenditure(metabolic, physical and intellectual). Our genes and environment also have a role to play. Good management depends on two or three factors.


Carbohydrates are our main source of food energy. According to nutritionists, carbohydrates should make up at least half of our daily calorie intake. Surveys show that this is not the case. In fact, we eat too many fats and proteins (an average 39% and 17% respectively).

Our calorie intake from food is made up of different macronutrients: carbohydrates and proteins 4 kcal/g, fats 9 kcal/g and alcohol 7 kcal/g respectively. As well as the right balance of nutrients, it’s best to avoid consuming more calories than we need on a daily basis.


There’s one way of expending energy that gets very little attention - our basic metabolism (breathing, heart beat, blood circulation, etc). In short, the normal functioning of our body at rest. Our metabolism alone consumes around 70% of our energy, roughly 1400 kcal per day. If we add digestion, which uses an extra 10% of our energy intake, then even without any “effort” we’ve already used up a lot of energy!

Only 20% is used for physical exercise, that is, walking, shopping, running, etc.. That certainly sets the record straight!


The secret of a good energy balance? Self-denial is not the answer. According to nutritionists, this leads to frustration and relapses over the long-term. They recommend exercise instead. Daily physical activity for a better energy balance doesn’t need to be intensive or inconvenient.

Dancing? Gardening? Walking? Anything - as long as it’s regular!Walking your dog at a brisk pace for half an hour in the morning and evening is more useful, from this point of view, than reluctantly doing an hour of jogging a week.