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Physical Education


Energy requirements

The energy the body takes from food is measured kilojoules or kilocalories.You need enough energy to meet the demands of your BMR and PAL.

BMR stands for Basic Metabolic Rate; the number of kilojoules you use to stay alive each day.

PAL stands for Physical Activity Level; the number of kilojoules you use to fuel all of your physical activity.

BMR + PAL = your daily energy requirement.

Big people need more energy for BMR. Athletes in endurance events and hard training need more energy for PAL.

British heptathlete Jessica Ennis attempts the high jump

Photo courtesy of BBC Sport

Boxer Robbie Reid

A heptathlete and a boxer will have different energy requirements

If you consume [Consume: To eat and drink. ] more energy than you use you will put on weight. If you consume less energy than you use you will lose weight.

People who under-eat will not have enough energy to perform effectively.

Being overweight may not be a problem. It may be due to a person having a lot of muscle, rugby players for example, so it's not always harmful. However, people who are overfat [Overfat : Having excessive amounts of body fat. ] or obese [Obese : The official term for being very over-fat. Being obese is dangerous to health. ] will not be effective sportspeople.

Back to Factors affecting performance index

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