A new study shows that dark chocolate (containing 70% cocoa) reduces the production of free radicals after exercise.

Free radicals, otherwise known as reactive oxygen species (ROS) do some good in the body, but when overproduced – as is typically the case – they can cause some real damage. Too many ROS will overwhelm the body’s antioxidant defenses and contribute to oxidative stress, a condition linked to rapid aging and various disease processes.

In the study, researchers had a group of cyclists consume 100 grams of dark chocolate, a placebo, or nothing. The cyclists then rode for 2.5 hours at a 60% maximal oxygen uptake level.  It was noted that in those riders consuming the dark chocolate, there was a significant increase in antioxidant levels before and after the cycling compared to the placebo group.  It was also noted that the cyclists who ate it also had more even blood sugar levels before and after the cycling period.

So what does this mean?

It means that chocolate (and we’re talking the REAL stuff here – not a candy bar!) can lessen the burden of oxidative stress from exercise. In other words, it lowers the amount of damaging free radicals in your body. That is good.

Should you eat cocoa now before exercise?

Let’s put it this way. While it has some good health benefits (and its full of simple carbohydrates, a bit of protein and fat), you probably want to stick with your typical pre-workout nutrition of whole foods.  The antioxidants in fruits and vegetables you eat will have the same effect as the chocolate in lowering oxidative stress. 

As an aside, the researchers also looked to see if it would boost immune function (which is commonly lowered as a result of intense exercise) – it didn’t.

Reference:

Glen Davison, Robin Callister, Gary Williamson, Karen A. Cooper, Michael Gleeson. “The effect of acute pre-exercise dark chocolate consumption on plasma antioxidant status, oxidative stress and immunoendocrine responses to prolonged exercise.” European J Nutrition, 5 April 2011