Dietary carbohydrates are a vital source of energy in the body, supporting optimal effort during both aerobic (cycling, running, swimming) and anaerobic (weights) activity.
Carbohydrates & Muscle Building
Carbohydrates also play an indirect role in muscle building. When carbohydrate is consumed together with protein in optimal amounts, the presence of energy-giving carbs helps block the wasteful conversion of protein into energy, ensuring maximum protein is freed up purely for muscle development. This is particularly important within the first half hour after exercise, a critical period of feeding in the recovery process.
Carbohydrate Glycogen Stores to Maximise Endurance
Carbohydrates can only be stored in very limited amounts within muscle and liver cells as a complex compound called glycogen. When glycogen stores are fully loaded, they function as a fuel source for strenuous activity, but will become depleted as exercise continues beyond 60-90 minutes.
During aerobic and prolonged exercise, when glycogen stores become depleted, high intensity performance can no longer be supported, so performance can only continue at 65-70% maximum output. This can seriously jeopardise an athlete’s chances of success, particularly in contact sports or in pure endurance disciplines.
Carbohydrate nutrition is vital for refilling glycogen stores to fuel ongoing endurance activity.
Carbohydrates & Weight Training
Carbohydrate is the only fuel source that can be broken down under anaerobic (nonoxygen dependent) conditions. Carbohydrate is therefore vital for weight training.
Intake of high-GI carbohydrate creates an insulin spike. The hormone insulin is often blamed for body fat storage because it has the ability to flush out excess sugar from the bloodstream and redirect it into the cells as body fat. However, eating carbohydrate following a fast period (or after exercise) does not have this effect. In fact, insulin release is important for muscle growth and recovery, as its activity is highly anabolic.