I know it’s cool to gang up on carbs these days, but science just doesn’t agree with the anti-carb pop culture.
In the pages of Rocket Fuel, I make a case for why athletes need not shy away from consuming carbohydrates. I know it’s cool to gang up on carbs these days, but science continues to show that carbs are what can help get you to the finish line with energy to spare.
Case in point: In a fascinating 2016 Journal of Applied Physiology study, researchers provided runners with a carb-based meal before a treadmill run to fatigue as well as a trial involving the carb meal and a special compound that restricts the body’s ability to use fat as an energy source during exercise. The subjects ran at the equivalent of 95% of their personal best half-marathon times. The result was that the runners ran equally well in in both trails. The upshot is that at this intensity, an active body much prefers to use carbohydrate as a fuel source as indicated by the fact that even when fat was available it did not result in improved performance compared to when fat-burning was hindered by the researchers.
In a follow up study, cyclists performed time trails after consuming a breakfast containing 2 grams of carbohydrates per kilogram of body weight and either a fat blocker or a placebo. The results showed that there was no significant difference in the time to complete the 60 and 90 minute time trials. So, again, even though fat was available as an energy source when no fat blocker was administered it did not alter performance indicating that the body had no real use for fat to generate energy. As along as enough carbs were available that is what the muscles turned to. Performance was hampered in the fat-blocking trial for the 120 minute cycling effort. This suggests that carbohydrate stores in the cyclists started to run out and there was no other viable fuel to turn to. This presents a good argument for fueling with extra carbohydrates in long lasting events.
Despite the internet buzz about the benefits of high-fat, low-carbohydrate diets for endurance sport, these results indicate that a diet high in fat and protein at the expense of carbohydrates will very likely hinder performance during high intensity exercise efforts by impairing the body’s ability to tap into carbohydrate stores as a vital energy source. In short, its carbohydrate availability that is rate limiting for performance with most endurance sports. That is why in a recent review of 61 studies, researchers determined that consuming extra calories from carbohydrates is a surefire way to improve endurance exercise performance.
Rocket Fuel provides a bounty of recipes that will give you the quality carbohydrates needed to keep up with the competition. Oats and sweet potatoes, anyone?
In Rocket Fuel: Power-Packed Food for Sports & Adventure, award-winning dietitian Matt Kadey offers up 120 delicious, creative, and convenient real-food recipes to power your everyday exercise and weekend adventures.
Rocket Fuel is available now in bookstores, outdoors stores, and online from these online retailers:
Barnes & Noble
Chapters/Indigo and MEC.ca in Canada
Food photography by Aaron Colussi.