The energy demands necessary to race at maximal effort during a triathlon are staggering. Endurance athletes and triathletes need to consume some form of glucose during the race so that their brains can continue to function properly. Very low blood sugar during a triathlon affects the brain adversely, causing dizziness, loss of consciousness and, in extreme cases, convulsions.
Brain Food
Brain cells feed exclusively on glucose. Glucose derived from carbohydrates during a triathlon not only keeps the muscles functioning, it also keeps the brain lucid, aware and in control. Neurons -- the nerve cells housed in the nervous system responsible for transmitting information -- do not have the capability to store glucose; therefore, the blood must provide it on a constant basis.
Bonking
The body stores glucose in the liver, but only enough to last 12 hours at rest. During intense physical activity such as a triathlon, the large muscles draw tremendous amounts of glucose from the liver, which quickly depletes its stores. If the liver runs out of glucose, the blood sugar dives, which results in fatigue, confusion, dizziness and, in extreme cases, what's known as "bonking," wherein the triathlete will lose consciousness and experience convulsions.
Simple and Complex Carbohydrates
Complex carbohydrates such as oatmeal, sweet potatoes, brown rice and lentils are denser forms of carbohydrate that release glucose slowly into the bloodstream. Simple carbohydrates include corn syrup, fruit juice and soft drinks. Triathletes are best served by combining both complex and simple carbohydrates -- complex carbohydrates before race day, and simple carbs during -- to ensure adequate amounts of glucose can be stored as well as utilized during the race. Energy gels offer triathletes a means to replenish glucose while racing to keep the brain nourished.
Warning
Low blood sugar is a very dangerous condition for triathletes, especially if your blood sugar bombs in the middle of the race. Loss of consciousness can lead to severe head injuries from falling off a bike or falling into the path of other cyclists or runners. Make sure that you nourish your brain adequately before and during the race. Speak to your doctor or nutritionist about your blood sugar if you regularly feel lightheaded or dizzy while competing in triathlons.
