Metabolism, what is it?
Metabolism refers to all the chemical processes going on continuously inside your body that allow normal functioning. These processes include breaking down nutrients from food and how they are used to build and repair our bodies. Building and repairing the body requires energy and that comes from your food.
The amount of energy is measured in kilojoules (kJ) that your body burns at any given time is affected by your metabolism. Maintaining or achieving a healthy weight is a balancing act. If you regularly eat and drink more kilojoules than we need for our metabolism you will most likely store is as fat.
Most of the energy we use each day is used to keep all the systems in our bodies functioning properly. This is out of our control however you can make your metabolism work for you through exercise. When your body is active your body burns kilojoules.
Metabolism rate can be divided into three components:
- Basal metabolism rate (BMR): Even while resting our bodies need energy. This accounts for the largest amount of energy expended during the day – 50-80% of your daily energy use.
- Thermic effect of food (also known as thermogenesis): This is the energy used to digest your food and drinks you consume, and its absorption, transport, and storage. This accounts for 5-10% of your daily energy use.
- Energy used during physical activity: Energy used by physical movement varies depending on how much energy you use each day. Physical activity includes planned exercise like going for a run or playing sports. This also includes incidental activity like hanging out the washing or playing with the family pet. Based on a moderately active person (30-45 minutes of moderate-intensity movement activity per day) this component contributes 20% of our daily energy use.