We can’t promise that dark chocolates for Valentine’s Day will help your relationship figuratively “go the distance” — but new basic research suggests cocoa compounds might literally help you go the distance, by running longer and stronger!

In a recent study from the University of California-San Diego, mice were dosed twice daily with epicatechin, a chocolate flavonoid, for two weeks to see how that might affect performance on a treadmill. Compared with a placebo, the cocoa compound mice were able to run 50% longer and enjoyed 30% greater endurance. Why might this be? The cocoa mice had an almost 30% greater density of leg muscle capillaries — which in turn allowed them to deliver more oxygen to their muscles. These mice also had a 50% increase in muscle proteins that support mitochondria (the “power plants” of cells).

Enhanced sports performance is just one of the cocoa benefits currently under study. Other research indicates that dark chocolate compounds may reduce blood stress markers, lower blood pressure, limit blood clotting and improve arterial flexibility. Keep moderation in mind, however, as even a one-ounce size serving of dark chocolate supplies 34% of your daily saturated fat limit and 168 calories. Try this issue’s Featured Recipe, Chocolate Dipped Strawberries for a delicious way to increase epicatechin levels. Or keep it simple by mixing a teaspoon of pure cocoa with a no-calorie sweetener and soy milk.

Bonus: Cocoa isn’t the only compound associated with enhanced athletic prowess — research suggests you can also boost stamina with beets, increase speed with astaxanthin (found in golden tomatoes and carrots) and exercise longer with quercetin, found in apples, onions and berries.

Published February 1, 2012