What are carbohydrates?
There are two main classifications of carbohydrates: simple (mono- and disaccharides) and complex (polysaccarides).
Simple carbohydrates - consist of one to two sugar molecules joined together. Simple carbohydrates require very little breakdown and thus are absorbed quickly by the body resulting in a rapid surged of energy. Common examples are:
- Glucose - is one of the primary molecules which serve as energy sources for plants and animals. When the body metabolizes glucose, it produces carbon dioxide, water, and some nitrogen compounds which provide energy.
- Fructose - or fruit sugar is found in fruits and vegetables.
- Galactose - or "milk sugar", which is the combination of glucose and lactose.
40-60% of daily calories should come from carbohydrate sources and should equal 6-10 grams of carbohydrate for every kilogram of body weight. - C.J. Osier, MDCarbohydrates are stored in the liver and muscles as glycogen which can be depleted during endurance sports. Since the body can't store a lot of glycogen, carbohydrates should be consumed during exercise to maintain blood levels.
What is carbo-loading?
Carbohydrate loading is a sports nutrition strategy that involves eating a higher than usual carbohydrate intake for 1-4 days prior to an event while tapering training. It may enhance performance by maximizing muscle carbohydrate (glycogen) stores prior to competition. High endurance sports such as long distance running, cycling, triathlon and cross country skiing depend heavily on carbohydrates as a fuel source and many athletes use this strategy to maintain their energy during training and competition.
Any performance nutrition strategies should be tested in training before use in a big competition to ensure there are no negative effects. Good nutrition is not a guarantee for athletic success, but it is still an important contributor to optimal performance.
References from the SIRC Collection:
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2. Clark N. Eating for endurance: Strategies for extraordinary athletes. ACHPER Active & Healthy Magazine. March 2007;14(1):8-9.
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4. Nugent L. Eating for Competing. Modern Athlete & Coach. January 2013;51(1):25.
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6. Twombley B. BEFORE & AFTER. Volleyball. August 2012;23(7):20-21.
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