Get Into Better Shape With (a Little) Dark Chocolate

Finally, a nutrition study we can cheer about — especially fitness-oriented, dark chocolate fans.

Yes, researchers from Kingston University in England have found that a small dose of dark chocolate every day (1.4 ounces, or about a square and a half, depending on the brand) improved the performance of recreational cyclists. The researchers were quick to add that eating any more than that would be unlikely to offer additional athletic benefits.

In other words, don’t gobble down an entire chocolate bar every day, for whatever reason, because the risk of weight gain and other potentially negative effects would overwhelm any benefits.

So let’s just be excited to hear (not for the first time) that a little bit of dark chocolate can be considered a nice, not naughty, treat—while also improving the delivery of oxygen to the body’s cells during exercise.

Marie Almon, a registered dietitian with Baptist Health Primary Care, is “not at all surprised” at the results of the study, published in The Journal of the International Society of Sports Nutrition.

“Basically, I’ve always been a fan of dark chocolate,” said Ms. Almon, who has worked on recipes with preventive cardiologist Arthur Agatston, M.D., one of Baptist Health’s medical directors of wellness and prevention and the best-selling author of The South Beach Diet. “Dark chocolate is part of a healthy diet.”

Lower in Sugar, Higher in Nutrients

Ms. Almon stresses that it is dark chocolate (“the darker the better,” but at least 60 percent cacao) that offers the most benefits because it’s lower in sugar than milk chocolate and higher in the beneficial nutrients like resveratrol and epicatechin.

Resveratrol, a plant compound, is believed to help protect people from various age-related conditions, including heart disease, Alzheimer’s and diabetes. It may even limit the spread of cancer cells.

Epicatechin, another plant nutrient found in cocoa, seems to improve cardiovascular performance, this new study found. Epicatechin encourages the release of nitric oxide, which improves blood flow by dilating the veins and arteries. It also stimulates the flow of oxygen into cells and additional blood sugar into muscle.

For the study, eight male cyclists were tested for their fitness during a moderate ride and a full sprint in a lab setting. After that, for two weeks, half of them ate the dark chocolate daily; the other half were given the same amount of white chocolate every day. Then their fitness level was tested again. Next, for another two weeks, the cyclists who had eaten dark chocolate were given the white chocolate, and the white chocolate eaters were give dark chocolate. All the cyclists did the same training routine and followed the same diet during the study.

Cyclists Used Less Oxygen, Peddled Further

The results were significant: All the cyclists performed better—though the improvements were modest—after eating the dark chocolate than they did after eating the white chocolate and in their baseline tests done before the chocolate consumption began. They used less oxygen, while pedaling moderately, and they rode further (another tenth of a mile) during the two-minute sprint.

Recreational athletes interested in even slight performance improvements can get creative with their small dose of dark chocolate. Ms. Almon suggests enjoying strawberries dipped in dark chocolate, for example. Just keep in mind the small serving size.

“We never want people to pig out. You can’t have a whole bar,” she said. “But a one-inch-square piece every day is just fine, and that has been part of my nutritional counseling for years.”