If you're skeptical about the benefits dark chocolate has to offer, read all about 'em here. And if you still need more convincing, check out this new study from Kingston University in London: Researchers found the bitter-sweet treat can give athletes an edge in their fitness training.
The inspiration behind the study is simple. Beet juice, which has been touted as one of the best all-natural performance boosters, is rich in nitrates. When nitrates are converted into nitric oxide in the body, blood vessels swell and reduce the amount of oxygen your body eats up, so you can exercise further for longer. Dark chocolate is rich in a substance called epicatechin, a nutrient-rich flavanol found in the cacao bean that also increases nitric oxide production in the body. So, researchers put dark chocolate to the test—to see if it can match or even exceed the benefits of beet juice.
In the study, published in the Journal of the International Society of Sports Nutrition, the Kingston U. team corraled a group of nine amateur cyclists. After completing an initial fitness test to establish a baseline for comparison, the participants were split into two groups. The first group was asked to replace one of their normal daily snacks with 40g (about 4 squares) of flavonol-rich dark chocolate for two weeks, while the other participants served as the control, substituting 40g of white chocolate for one of their daily snacks.
Cycling tests ensued. During time trials, cyclists' heart rates and oxygen consumption levels were measured to track the effects of daily chocolate consumption. After a seven-day interval, the groups switched the type of chocolate they munched on every day. Another two-week trial and subsequent exercise tests were repeated.
All in all, the dark chocolate-snacking riders used less oxygen when cycling at a moderate pace, and also covered more distance in a two-minute flat-out time trial than the white chocolate-snackers. The dark chocolate altered participants' response to aerobic activity, which enhanced their overall performance.
Did researchers just give the green light for dark chocolate becoming a staple part of athletes' diets? Pretty much! Now they're hoping to nail down the specifics.
"We want to see whether the boost in performance is a short term effect—you eat a bar and within a day it works—or whether it takes slightly longer, which is what the initial research is showing," lead study author Rishikesh Kankesh Patel said in a press release. "We are also investigating the optimal level of flavanols. At the moment there is not a lot of consistency in flavanol levels in commercially-available chocolate. Once we've found the optimal chocolate dose and duration, we'll compare its effects to those of beetroot juice, and also test the influence of combining consumption of both, as they produce an increase in nitric oxide in slightly different ways."
And, if you're among the majority who struggles to put down beet juice but wants to reap the benefits, dark chocolate couldn't be a better (just as effective) alternative. Opt for higher percentages (70% and up) of cacao when you shop for dark chocolate; it means there's a higher amount of flavanols.