Carbohydrate

Foods containing carbohydrate are the essential source of energy for most forms of exercise. Carbohydrate is stored in the muscles and liver as a substance called glycogen, which is broken down to release the energy needed for all aspects of life. But the body's stores of glycogen are limited – we only have enough to keep us going for about 1.5 to 2 hours of moderately strenuous exercise. If we allow the stores of glycogen to dwindle as a consequence of a poor diet, our exercise capacity is reduced still further.

It is recommended that people who exercise make sure that 60–70% of their total energy intake comes from carbohydrate. Carbohydrate can be obtained from either starch- or sugar-based foods, like those listed here:

• Bread

• Pasta

• Potatoes

• Bananas

• Breakfast cereals

• Sweetcorn

• Fruit including fruit juice, jams and dried fruit

• Energy snacks, chocolate bars and confectionery

A sensible mix of both starch- and sugar-based carbohydrate foods is the ideal way to obtain the energy needed for exercise.