Almost everyone who visits a gym has the goal of losing body fat. While losing fat may seem easy, it requires a combination of diet and exercise to see results. There are a variety of benefits to burning fat, but it is important to understand that this can only happen when the body is using all its energy sources.
When the body uses carbohydrates for fuel during exercise, the carbs are converted to glycogen and then broken down to supply the muscles with energy. This process is called oxidation. During moderate exercise, the body also breaks down some of its stored fat cells to supply energy. However, the proportion of fat used for fuel during exercise varies. During lower intensity workouts, the body tends to use more fat for energy, but as exercise intensity increases, the body relies less on fat and more on carbohydrates.
Many exercisers strive to stay in the ‘fat burning zone’ during workouts, which is an area of the heart rate spectrum between 70 – 80% of maximum heart rate (MHR). The theory behind the fat burning zone is that exercising at this level of intensity will encourage the body to burn more fat calories for energy.
However, the concept of the fat burning zone is flawed. Athletes who exercise at this level of intensity are actually exerting themselves a lot harder than they think. This level of effort is a good indicator of the body’s fatigue, but is not indicative of whether or not the athlete is using fat as fuel for its efforts.
The body relies on various energy or fuel sources for its activities, including glucose (blood sugar), glycogen stored in the liver and muscle and fatty acids stored in adipose tissue. Carbohydrates are used for energy during low to moderate activity levels, but the body primarily uses fat as energy for high-intensity exercises or when calorie intake is restricted (Coelho et al, 2013).
When fat is burned for energy, the process of Lipogenesis is involved. This is the process whereby carbohydrates are metabolized to release fats into circulation for energy (Trayhurn and Wood, 2004). The released fatty acids can then be used for new protein synthesis or stored in adipose tissue as triglycerides.
Fats are not just a source of energy, they are also vital for the function of the body. Adipose tissues secrete a number of hormones that serve a wide range of functions, including regulation of blood glucose, control of appetite and the immune system.
It is possible to increase the amount of fat burned during exercise by controlling your carbohydrate intake and exercising at a moderate intensity. However, it is important to note that this will only have a small effect on weight loss, as most of the calorie expenditure in the exercise session will come from other fuel sources. The best way to increase your fat-burning potential is through a diet that includes healthy foods and regular exercise. Fettförbränning