If your body weight is within the normal range and you are involved in lots of extra activity or playing sport, you need to ensure you keep up your energy intake.
We get energy in three different forms from the foods we eat - protein, fat and carbohydrate. All of these are essential in the diet and provide many important nutrients as well as energy. So what are the differences?
Carbohydrates include starches, sugars and fibres and are the body's preferred fuel for activity. Try to make up the bulk of your diet with high carbohydrate foods (up to 50-55% of energy should come from carbohydrates). Good choice high carbohydrate foods which provide energy, fibre and vitamins and minerals include; breads, cereals, rice, pasta, fruit and vegetables.
Foods that contain carbohydrates mainly in the form of sugar and have very few other nutrients, such as soft drinks and lollies, should be kept to a minimum in the diet. Have these as treats only.
Proteins are the building blocks of body tissues such as muscles. About 15% of our day's energy should come from protein. Good choice high protein foods include meat, fish and chicken, dairy products, legumes (including baked beans and pulses), nuts and eggs.
Fats in the diet are needed to supply energy and essential fatty acids for normal body growth and function. About 30-35% of our energy should come from fat. There are different types of fats and those that are higher in monounsaturated or polyunsaturated fats such as oils, avocado, nuts and seeds are considered better than those higher in saturated fats.
It is important to understand that the amount of energy supplied by fat is different to both protein and carbohydrate. If you eat one gram of fat you will get 37 kJ of energy, whereas one gram of either carbohydrate or protein will give you only 17kJ of energy. This is why fats are considered a more concentrated source of energy.
Fuel your activity - before exercise
Muscles use glucose to supply the energy they need for exercise from the blood or the body's stores. The more often you exercise the more your body will adapt and build up its stores to ensure there's plenty of glucose available for all the activity you are doing. You can boost your stores the day before a big event by having a high carbohydrate meal - "carbo loading". Drink plenty of fluids too.
Some suggestions for 'carbo loads':
- Baked beans or spaghetti on toast
- Pasta with tomato & vegetable sauce
- Baked potato with creamed corn or other vegetables
- Breakfast cereal with low fat milk and fruit
- Minestrone soup with toast
- Chili con carne - mince with beans & vegetables on rice
On the morning of a big event or game you may wish to boost your carbohydrate intake again. It can be a good idea to avoid very high fibre foods on the day of a big sporting event in case it gives you some stomach discomfort.
Some suggestions for pre-event meals:
- Banana, milk and yoghurt smoothie
- Crumpets or muffin splits with honey or syrup
- Pancakes with banana and other fruit
- Spaghetti on toast and a glass of fruit juice
- Fruit salad (canned & fresh) with yoghurt
- Milo made with low fat milk
- Creamed rice
Don't forget plenty of fluids!
If your event is later in the day, you may want to have a hearty breakfast and just a light meal or snack a few hours before the event.
Fuel your activity - during exercise
The most important thing to remember is to keep up your fluids. If possible have a drink of water or a sports drinks midway through the game or event.
For endurance events you may need to take some easily digested snacks to keep you going. Foods higher in sugar are okay here, such as sweets or chocolate, a sports bar or gel, or a banana. If you find solid food too hard on the stomach, use a sports drink, fruit juice or cordial.
Fuel your body - after exercise
It is really important that you do not neglect your body after strenuous exercise. You need to refuel and replenish your lost fluids. Eating for recovery has two important stages. As soon as possible after your event, eat a snack such as a banana, some creamed rice, cornflakes, sugar based biscuits or bread.
Later, eat more substantial carbohydrate rich foods such as pasta, baked beans, rice or bread. Try a tuna, peanut butter or banana sandwich. Remember to drink regularly after the event.
It is really important you make sure you drink enough fluids. Drinking at least six to eight glasses of water a day is ideal but if you are exercising you will need even more. You can lose as much as two litres of fluids when exercising hard. Aim to be well hydrated before activity and make sure you replace the losses soon afterwards.