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Carbohydrate-rich foods include grains, cereals, dairy produce, fruit, certain vegetables, sports-specific products and sugar. The amount you need depends on your training programme and other dietary goals. Your training requirements will be in the range of 5–7g/kg body weight, with a maximum of 600–700g per day (60% of energy intake, or more). However, this may vary depending on your daily energy expenditure, type of sport, gender and environment. In situations involving either extremely prolonged and intense exercise or repeated bouts within an 8–12 hour period, requirements may increase to 8–10g/kg body weight. In extreme sports such as the Tour de France, this may be as high as 12g/kg body weight (see p168). For weight loss, carbohydrate intake may be reduced to 3–4g/kg body weight.

Every plate of food you eat should contain at least 50% carbohydrate-rich foods (see p23). First determine your total daily carbohydrate requirements in grams, then divide that figure by 50, for the number of carbohydrate servings needed per day. Then select the appropriate number of items from the list of 50g carbohydrate servings (see opposite).

Carbohydrate is stored in the liver and muscle as glycogen. The liver glycogen is broken down to glucose and released into the bloodstream to ensure a constant supply to the brain and muscle.

GRAINS 1 CUP = 250ML (9 OZ)

▪ 3 thick slices bread

▪ 10 crackers or 6 rice cakes

▪ 500ml (2 cups) high-fibre (bran) cereal

▪ 3 breakfast wheat biscuits

▪ 500ml (2 cups) porridge

▪ 250ml (1 cup) pasta or 1 heaped cup rice

▪ 250ml (1 cup) samp/polenta/couscous

▪ 3 medium bran muffins

▪ 2–3 muesli or breakfast bars

VEGETABLES & LEGUMES

▪ 250ml (1 cup) baked beans

▪ 830ml (3⅓ cups) peas; or carrots; or butternut; or mixed vegetables

▪ 3 medium potatoes; or 250ml (1 cup) sweet potato (270g; ¼ lb)

FRUIT

▪ 3 medium pieces of fruit (apple, banana)

▪ 40ml (3½tbsp) raisins

▪ 500ml (17 fl oz) fruit juice

DAIRY

▪ 1ℓ (4 cups) skim- or low-fat milk or buttermilk

▪ 375ml (1½ cups) low-fat, flavoured, drinking yoghurt or 250ml (1 cup) fruit yoghurt

SPORTS PRODUCTS, SUGARS AND SWEETS

▪ 60ml (5tbsp) sugar

▪ 1 handful of jelly babies

▪ 10 marshmallows (100g; 3⅓oz)

▪ 1–2 sports bars

▪ 40ml (3½tbsp) glucose polymer powder

▪ 1–1½ sachets gel

▪ 500ml (2 cups) liquid meal replacements (made with low-fat milk or water)

▪ 800–1000ml (1½–2pt) sports drinks

▪ 500ml (17 fl oz) cola or other soft drink

List of 50g carbohydrate servings from which to make up your total daily requirement.

Practical tips

1. Enjoy a variety of carbohydrate-rich foods to optimize your nutrient intake, focusing on nutrient-dense carbohydrates that are also rich in vitamins, minerals and fibre (wholegrain cereals, fruit and vegetables).

2. Split your total carbohydrate needs into several meals and snacks throughout the day.

3. Always have portable choices such as fruit, yoghurt, sports bars and dried fruit on hand.

4. Carbohydrate-rich foods are sometimes classified according to the speed at which they are absorbed from the blood. This is referred to as the glycaemic index (GI). High GI, carbohydrate-rich foods are absorbed more quickly (sports drinks, energy bars, bread and jam) and are therefore good choices after exercising.

5. If you have little appetite and/or suffer from stomach discomfort (for instance, before exercising), then compact, easily digestible carbohydrate foods should be eaten – sweetened, low-fibre breakfast cereals, white bread with honey or jam, or sugar. Carbohydrate glucose polymer powders can be added to foods and drinks to boost your carbohydrate intake. Liquid meal supplements can also be used.

6. Decrease your carbohydrate intake when your training decreases (for instance, in the off-season or when injured) to prevent unnecessary weight gain.

7. Sports drinks can help you meet your daily carbohydrate needs, but not as a main source of carbohydrate, because this will reduce your vitamin, mineral and fibre intake and may lead to weight gain.