When you think of foods that improve athletic performance, chocolate might not be the first item that comes to your mind.
We have known for a while that certain compounds naturally occurring in chocolate, known as flavanols, are good for your heart. Epicatechins, the most prevalent flavanol in chocolate, seem to have especially compelling benefits for cardiovascular health.
But some evidence suggests that chocolate may also aid in exercise performance. Here’s what the research says - and how you can take advantage of it for yourself.
How Cocoa Works
A while back, researchers became interested in how epicatechins in chocolate could influence aerobic capacity.
To test this, they randomly allocated mice into four different conditions:
- Water + exercise
- Epicatechin-infused water
- Epicatechin-infused water + exercise
Groups 2 and 4 were put on an exercise program via treadmill. The other mice just chilled, and presumably did typical mouse things for the ensuing period.
After 15 days, the researchers performed biopsies of their hind legs, and observed some interesting differences. They found that both groups of mice that had been given epicatechin had grown more capillaries in their leg muscles, which would enable their muscles to get more blood flow. Their muscle cells were also generating more mitochondria. More mitochondria means greater energy production, and better resistance to fatigue.
Both of these factors would be expected to improve aerobic metabolism in the muscles. So the researchers put this to the test, by forcing all of the rodents to run on a treadmill to exhaustion.
Sure enough, the control mice drinking plain water became tired sooner than their counterparts that were assigned epicatechins. In fact, the mice that had been drinking water and training on the treadmill did about the same on the treadmill test as the mice that were given the cocoa polyphenols but who didn’t work out!
But the fittest mice were in the group that both exercised and consumed epicatechins. This group ran approximately 50% further than the animals that did not consume the flavanols.
Cocoa and Human Performance
Obviously, what works in rodents doesn’t always pan out in humans. So what happens when people are put on a similar regimen?
To explore this question, a team of researchers from Kingston University in London took nine amateur cyclists and split them into two groups. One group added dark chocolate to their diet; the other added white chocolate (virtually no flavanols) in their diet as a control. After two weeks of this protocol, the cyclists performed a series of exercise tests. Then the cyclists switched chocolate types, and repeated the experiment.
The researchers found that when the cyclists ate dark chocolate, they consumed significantly less oxygen when they were riding, and were able to cover 17% more distance during a 2-minute all-out sprint. Not bad, for an intervention as easy as eating chocolate!
Before you go grab some leftover Easter bunnies, keep in mind that not all chocolate is created equal - at least from a physiological standpoint.
What kind of chocolate are we looking for here?
The type of chocolate makes a really big difference here. Milk chocolate, sadly, is really low in flavanols, so it’s not a great choice. Epicatechins are found most abundantly in unsweetened cocoa powder and unsweetened baking chips. If the bitterness of these products is a dealbreaker for you, dark chocolate (like around 70%) has about half as much, but it’s a lot tastier. Also, you want to look for chocolate that has not been alkalized (aka Dutch processed). When cocoa is processed with alkali, the flavanol content goes way down.
How much do you need?
Fortunately, the effective dose is actually pretty realistic. In the mouse study I described above, the rodents were given 1 milligram of epicatechin per kilogram of body mass. This would translate to roughly 5 grams of dark chocolate when scaled up to humans, depending on the weight of the human in question. But of course, we can’t necessarily assume that the effective dose for mice and for man would be the same. The cyclists in the other study, for instance, ate 40 grams of Dove dark chocolate.
If you really want to optimize, you can use a highly concentrated form of cocoa powder, like CocoaVia, which is my own preferred strategy. Each 6-gram scoop contains 500 mg of cocoa flavanols (and only 10 calories). I add one scoop to my coffee every morning and mix it up with a milk frother.
Can I just eat dark chocolate and skip the workouts?
Okay, you already know the answer to this one. Actually, some research does suggest that dark chocolate can trigger improvements in exercise capacity in sedentary people, which is pretty cool. In fact, epicatechin is being investigated as an exercise mimetic (i.e., it activates some of the same biochemical cascades as exercise, and thus produces some of the same benefits). However, the stimulus of exercise is still an essential factor. Plus, physical activity does a whole lot of other things that you can’t really achieve with chocolate.
“Exercise in a pill” is a tantalizing idea, but we are still a long way off from realizing it. As with many things in life, hard work is key to see the results you want. But nutritional components like dark chocolate can certainly help you along the way.