. With a focus on fruit, vegetables, whole grains, low-fat protein foods, nuts, beans and lentils, the foods you eat will result in a steady level of sugar in the blood stream. "You will be full of energy, which is perfect for runners," says Bean.Take away

of eating healthily throughout the day," says Bean. "You also fuel your body so you feel happy and energised for the rest of the day."The Low GI Diet (hodder mobius, £6.99) Take away tip Filling up on fibre-rich low-GI foods with a high water content

going for longer. It's also great if you're trying to lose weight as it keeps you feeling full. Fruit and fibre In other words, fresh fruit and foods that are packed with fibre. A recent study in the International Journal of Sport Nutrition and Exercise