Metabolism is a term that’s widely used, especially in connection with gaining weight or losing it. But what does it really mean?
Put simply, metabolism is the sum of the chemical reactions that take place within each cell of your body that provide energy for vital processes in order to maintain life.
The rate at which your body uses up kilojoules (or energy) to carry out these vital metabolism functions is called the metabolic rate:
Your BMR can be influenced by many factors including your body size, age, gender, genetic predisposition, hormones and what you eat. The amount of exercise you do can have an effect as well.
It’s all to do with muscle. Compared to women, men’s bodies generally have more muscle and less fat which makes a difference to your BMR. While fat burns very few kilojoules, muscle is an active, ‘hungry’ tissue that uses up kilojoules even when you’re just sitting around.
Exercise increases the amount of muscle you have — and the more muscle you have, the faster your BMR will be. Exercise will generally help increase muscle. Studies show strength training (also known as resistance training or weight training) builds muscle more effectively and increases BMR.
Nutrient Reference Values: Dietary Energy
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Last Updated: 6 June 2013
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Last published 31 October 2010