Top Questions on Nutrition and Swimming
BY Chris Rosenbloom, PhD, RD, CSSD
Here are some of the top questions I’ve gotten from my readers.
Question: Is fruit juice a good beverage for a young swimmer who is trying to gain weight?
Answer: Fruit juice is a good carbohydrate source and a high calorie drink, so it is good for swimmers who are trying to gain weight. Look for 100% fruit juice and not fruit drinks which contain added sugars. Real fruit juice has simple carbohydrates (natural sugar) and vitamins and minerals so it is a nutrient-rich beverage. Fruit juices with the highest calories include grape juice and pineapple juice (152 and 132 calories per cup of unsweetened, natural juice) while orange and apple juice contain less calories (114 and 115 calories per cup, respectively). Fruit juice is best used as a recovery beverage or with meals. Some people don't recommend drinking a high glycemic index carbohydrate (like fruit juice) right before a workout because it might raise blood sugar and insulin levels which might affect performance. However, as a post-workout beverage, it could help the muscles restore glycogen rapidly to get ready for the next day’s workout.
You might also try some of newer fruit juice blends (cran-grape, berry-orange, etc.), but read the nutrition facts panel to find a juice without added sugars. You can always make your own juice with a home blender. Toss in strawberries, apple slices, bananas, or orange sections and find a favorite mix for homemade juice.
Question: My son has tried two different recovery products for after swim practice, and we are trying to figure out which one is the best for him. One is a chocolate milk product and the other a fruit smoothie with protein. Is there an ideal carbohydrate-to-protein ratio that we should use to evaluate products?
Answer: I don't look at a specific carb-to-protein ratio because the science isn't that clear cut, but what is pretty well established is that the protein sources of whey and casein appear to be best for muscle repair and growth. So, I would give the edge to the chocolate milk product containing both whey and casein; the juice has slightly more protein but its source soy. Whey protein seems to have the edge for muscle protein synthesis because it is rich in the amino acid leucine, which may be a trigger for muscle protein growth (soy isn’t bad; it might just take longer to achieve results compared to whey). Research also shows that 20 grams of protein is probably the maximum needed for muscle recovery so assuming your son drinks the entire bottle of chocolate milk recovery product (the label shows that 8 ounces is a serving, but the bottle contains 2 servings) he will get 20 grams of high quality protein.
The best answer is that both are good products, so switch it up and use both to help restore muscle glycogen (fruit smoothie) and milk product for muscle repair. By changing up the drink you can avoid “taste fatigue” by using only one recovery beverage. As with any commercial product, it is good to check the nutrition facts panel and check the ingredient list to make sure it doesn’t contain any banned substances or an added protein source that may be from a banned substance. Products sold as dietary supplements, as opposed to foods, are more risky for athletes because they do not have any regulation from the Food and Drug Administration.
Question: I have a bet with my daughter. She says swimmers only sweat in land training, not when they are in the pool. I say she sweats in the pool but she might not notice it.
Answer: You are right. She does sweat during a long workout in the pool. When you add in the warm pool water and high humidity surrounding the pool water, she can sweat a lot in the pool. Hydrate to avoid more than a 1-2% loss of body weight during a workout to improve performance and stay healthy.
Chris Rosenbloom is the sports dietitian for Georgia State University Athletic Department and is the editor of recently published Sports Nutrition: A Practice Manual for Professionals, 5th edition, published by the Academy of Nutrition and Dietetics (2012).