Questions about what constitutes an ideal and practical diet for competitive athletes consume and confuse many athletes, as well as their coaches and families. But a new, comprehensive review about the science of sports nutrition published recently in Science provides a lucid overview of what currently is known — and not known — about how athletes should eat.
To find out more about these and other topics, I spoke with Louise Burke, a sports dietitian and professor at Australian Catholic University who has worked with many elite Australian sports teams. She wrote the new review with her husband John Hawley, the director of the Mary MacKillop Institute for Health Research at Australian Catholic University. What follows are edited and summarized excerpts from our conversation.
Q. In your review, you write that “carbohydrates are the predominant and critical substrate for working muscles” and that “the availability of carbohydrates, rather than fat, wins gold medals.” So athletes should be eating and drinking carbs?
A. Broadly speaking, if you had to stretch a big umbrella over the whole sports world and say, what dietary approach will bring the most performance benefits to the most types of athletes, then, yes, a high-carb diet would usually be the answer.
Q. In practical terms, how much carbohydrate are we talking about, especially during competition?
A. Based on what we know now, it looks like 30 to 60 grams of carbohydrates per hour during endurance events lasting several hours would be the sweet spot for most athletes. [For reference, a typical packet of a sports gel contains around 30 grams of carbohydrates, as does a banana or most single-serving bottles of sports drinks.]
Q. Some people, including me, might find it difficult to stomach so much food or drink during a race. Any advice?
A. Train your gut, just like you train your muscles. In the buildup to an event, practice with the foods or drinks you plan to have during the event, adding more, slowly. Some people find that combining multiple kinds of carbs, like glucose with fructose, are more tolerable than either one alone, probably because they are metabolized along slightly different pathways in the body. It’s also clear that you can swish sports drinks around in your mouth and spit without swallowing and your brain will interpret this as meaning you have more energy available. I think that’s fascinating and it can be useful, if you can’t stomach more carbs just then.
Q. The big controversy in sports nutrition right now seems to involve high-fat diets, which some people claim are better for performance than high-carb diets. Do we know whether one approach is really better for athletes?
A. [Dr. Burke noted that “the issue is so much more complicated than the Twitterverse would have people believe.” Carbohydrates remain muscles’ preferred fuel choice during exercise, she explained, because they can be metabolized so quickly. But our bodies contain much larger stores of fat than carbohydrates, so it makes intuitive sense that we might want to become better able to use that substantial fuel source, perhaps by eating a low-carbohydrate, high-fat diet.
Courtesy: The New York Times