During short term, intense exercise, carbohydrates are the main source of energy. Carbohydrates are made of carbon, hydrogen and oxygen and are classified as either simple or complex, based on the number of sugar molecules present.
Carbohydrate in the form of glycogen is the most readily available energy source. Compared to fat, carbohydrate provides energy more quickly, can be used whether or not oxygen is present and serves as the sole source of energy for the central nervous system.
During prolonged exercise, fats become the main energy source, and the shift from carbohydrate to fat utilization (carbohydrate sparing) is enhanced by physical training.
For the people of many countries, 80% of their total daily calories come from complex carbohydrates.
Carbohydrate such as starches and sugars are an efficient and readily available energy source especially for the brain. They are also necessary for fat and protein metabolism. Carbohydrates provide energy with 4 calories per gram.
Plentiful stores of carbohydrates in the body are important for excelling in physical activity, especially endurance exercise. During exercise utilization of carbohydrate accelerates an increased release for glucose from the liver is functionally important to maintain blood glucose homeostasis and to possibly attenuate muscle glycogen glycogen depletion.
If inadequate carbohydrate is available, the body burns protein for energy. This protein comes from food and from the body’s own muscle tissue.
Therefore, in cases of inadequate carbohydrate and protein intake, not only would muscle wasting occur, but adequate proteins would not be available for repair of body tissue.
Carbohydrate as a source of energy
