Carbohydrates
Why are carbohydrates important in exercise?
Carbohydrate (CHO) is an important energy source. It is stored as glycogen in the muscles and liver and as glucose in the circulating blood. During intense exercise, muscle glycogen is the primary energy source. As the duration of intense exercise increases, blood glucose becomes more important. Depletion of either source of fuel results in fatigue.
When to take carbohydrates
Consume carbohydrates 3-6 hours before physical activity. Either food or dietary supplements can be used to ensure adequate energy for an upcoming event.
There are two types of carbohydrate supplement. Complex carbohydrates, or polysaccharides, must be broken down before they can be absorbed and therefore they release energy at a slow and steady rate. Simple sugars, such as monosaccharides (glucose) or disaccharides (sucrose), are found in sports drinks and provide a quick spike of energy.
Before and after exercise
Look for slow-release carbohydrate supplements such as maltodextrin and other starches if you want to supplement before a bout of exercise to ensure high energy stores, or after the event to replenish spent energy.
During exercise
Consuming CHO during exercise can delay the onset of exhaustion. During exercise, consume simple sugars to maintain energy levels with a quick input of carbohydrate energy.
Avoid slow-release carbohydrate drinks during exercise. Their high concentration of carbohydrate delays emptying of the stomach which, during exercise, can lead to nausea and stomach cramps.