The American College of Sports Medicine (ACSM) is the world's largest organization of sports medicine and exercise science professionals. At ACSM's 2011 annual meeting in Denver, over 6,000 exercise scientists, sports dietitians, physicians and other health professionals gathered to share their research. Here are a few of the nutrition highlights:
- When athletes lose weight, they lose muscle as well as fat. For example, soldiers during nine weeks of combat training lost 9 lbs (4.2 kg) body weight, of which one-third was muscle loss and two-thirds fat loss. They consumed about 15% fewer calories than required to maintain weight.
- Even bodybuilders and figure competitors do not lose just body fat when they "lean out." In the 12 weeks pre-competition, male bodybuilders lost about 4 lbs (1.8 kg) lean body mass and 11.5 lbs (5.2 kg) body fat. The female figure competitors lost about 5.5 lbs (2.6 kg) lean and about 6.4 lbs (2.9 kg) fat.
- Trained cyclists who consumed equal calories of either a sports drink or banana chunks during a 75-kilometer cycling time trial performed similarly. The banana, however, offered a beneficial anti-inflammatory response. Natural foods generally offer more benefits than engineered sports foods.
- Chocolate milk is a popular recovery food that contains carbohydrates to refuel muscles and high quality protein to build and repair muscles. Both full-fat and skimmed chocolate milk offer similar recovery benefits.
- How common are intestinal problems during endurance events? About 31% of the Ironman competitors reported GI serious problems, compared to 14% of the half-Ironman competitors, 4% of the cyclists, and 4% of the marathoners. Those with a history of GI distress reported the most symptoms, as well as those who exercised in higher heat.
- If your child or teen is going to be competing in the heat, they might want to pre-cool their body. One way to do that is to enjoy an ice slurry. Runners who consumed about 14-ounces of ice slurry before they exercised in the heat were able to run about 1% faster during a 10 kilometer (6.2 mile) race.
- Female athletes commonly restrict their food intake. Of 44 female high school cross-country runners (16 years old):
- 39% restricted food, thinking being lighter would help them perform better.
- 42% reported missed or absent menstrual periods in the past year, which is a sign of being under-fueled, and were eight times more likely to believe missing multiple periods was a sign they were in better shape. [Clearly, these young women need to be educated about the medical problems associated with missed menstrual periods!}
- To resume menses, amenorrheic women need to correct the energy deficit.
- Those who drank a 360-calorie carbohydrate-protein supplement resumed menses, on average, in about 2.5 months (±2 months).
- The longer an athlete is amenorrheic, the longer it takes for her to resume menses.
Posted July 19, 2011