Saturday, October 29, 2011
Carbohydrate Requirements for Exercise
Carbohydrate Requirements for Exercise - from Nutrition Dimension. By Ellen Coleman, MA, MPH, RD, CSSD
Think of carbohydrates as the body's gasoline supply - easily converted to motion in whatever amount is required. To satisfy the demand, as long as it lasts, there must be fuel in the tank. With low-carb diets currently being promoted for weight loss, food and beverage manufacturers are pushing the idea of fewer calories from carbohydrates as a good thing. The problem is, athletes- and even regular exercisers- can run out of gas.
Adequate carbohydrate stores are critical for optimum athletic performance. Carbohydrate is stored in muscle and liver glycogen and in blood glucose. Consuming adequate carbohydrates on a daily basis is necessary to replenish muscle and liver glycogen between daily training sessions and competitive events.
Athletes in high-power activities often want to lose weight, and so consume low-energy diets. Inadequate energy intake can harm high-performance due to impaired acid-based balance, reduced enzyme levels in the anaerobic pathway, selective atrophy of fast-twitch muscle fibers, and abnormal muscle contractile function.
The majority of the carbohydrate should come from nutrient-dense carbohydrates (whole grain products, legumes, fruits, vegetables, and low-fat dairy products).
The article suggested about 50% of daily calories should come from carbohydrates - of course this depends on your activity level. That doesn't mean it should all come from cookies, cupcakes, rice or pizza.
Choose foods made with whole grains, such as whole wheat bread, brown rice, popcorn, oats and oatmeal. You may also find some whole grains new to you, such as millet, teff, spelt, kamut, quinoa or barley. Many of these can be cooked and used like rice for side dishes, pilaf, soups or stews.
All varieties of fresh, unprocessed fruits and vegetables are good choices, but steer clear of varieties with added fat, sugar or salt. Make an effort to eat the skin on apples, pears and other produce whenever possible because peeling them reduces both the fiber and vitamin content.