Whether we are active or sedentary our bodies require the same nutrients to keep us in good health. When taking moderate but regular exercise there is no need to make radical changes to the diet but rather, learn to appreciate that the balance of nutrients you require may differ slightly from those who take no physical activity at all.

It is especially important that, in addition to a variety of lean protein foods, fruits and vegetables, adequate amounts of carbohydrate foods are eaten to fuel the working muscles and replace carbohydrate energy stores used up during each exercise session. Failing to do so is the equivalent of trying to run a car on lower and lower levels of petrol. You will keep going for a while but eventually feel unable to keep going. Here are five top tips for getting your carbohydrates right.

1. Try to eat 5g of carbohydrate per kilogram of body weight each day. For a 70kg man this means having at least 350g of carbohydrate a day and for a 55kg woman, 275g.
2. To reach these figures have some carbohydrate foods at each meal. Try bread and bread products, pasta, breakfast cereals, rice, potatoes, beans, root vegetables, fruits and crispbreads.
3. Sweets, fizzy drinks, dried fruit and chocolate can be convenient and practical foods in the exercising diet, and are a less bulky source of fuel to boost carbohydrate intakes.
4. Ideally eat a meal containing carbohydrate 2 – 4 hours prior to exercise and a small snack such as a banana about an hour before.
5. Try to eat around 50g of carbohydrate within 2 hours of finishing exercise. This helps to refuel the muscles and should include some quickly absorbed foods such as digestive biscuits, chocolate bars, bananas, cornflakes, buns, sultanas, raisins or a glass of sports drink.

As well as thinking about carbohydrate, remember that you need lean sources of protein such as chicken, meat, fish, dairy foods and pulses to help maintain the body, and some fat. Try to regularly include some oily fish, olive oil and nuts and seeds that supply essential fats for smooth functioning of the body.

Of vital importance to anyone taking part in regular exercise is to make sure that you drink enough. The rule of thumb is to have at least 2 litres of fluid a day plus an extra litre for every hour of exercise. This can increase dramatically, however, in hot, humid conditions. Don’t rely on being thirsty to tell you when to drink, keep fluid levels up at all times before, during and after exercise.

Carbohydrate Portions

Food	Grams of carbohydrate (g)
230 g serving cooked pasta	50
60 g serving cornflakes	50
150 g serving rice	45
2 slices wholemeal bread	30
Toasted bun	30
54 g milk chocolate	30
2 scoops mashed potato	25
1 medium banana, apple or pear	20
160 ml serving orange juice	15

Further reading:

Sjöström M (editor) (1999) Diet and Physical Activity - Interactions for Health. Public Health Nutrition 2, Number 3(A).

FOOD TODAY 12/1999