21st December 2015

If you’re worried whether all that festive overindulgence will sabotage your training gains, then take comfort from a new study that suggests eating a little dark chocolate every day can actually boost your performance. This is welcome news indeed for chocolate lovers.

Scientists at Kingston University gave nine cyclists 40g of either dark or white chocolate every day for 14 days. They measured the cyclists’ fitness (via a VO2max test) and performance (via a 20-minute ride at 80% of their maximum and a 2-minute all-out sprint) before and after each 14-day period. Calories were kept the same throughout. After consuming dark chocolate for 14 days, the cyclists managed to cover 17% more distance in the time trial than they did at the start of the experiment and 13% more compared to eating white chocolate.

Their cardiorespiratory fitness (as measured by their ‘gas exchange threshold’) increased by 21% after 14 days of eating dark chocolate compared with their baseline values. White chocolate had no significant effect. In other words, dark chocolate reduced the oxygen cost of moderate-intensity exercise and improved the cyclists’ high-intensity (time trial) performance compared with white chocolate.

The secret ingredient? Scientists believe it’s most likely the high content of flavanols in dark chocolate that is responsible for its performance-enhancing benefits. These plant-derived compounds improve levels of nitic oxide (NO) in the body, increase blood vessel dilation and oxygen delivery to muscles, reduce oxygen demands during moderate-intensity exercise and enhance performance during high-intensity exercise. They work in a similar way to beetroot juice. But, for many, dark chocolate is a more palatable and convenient format to elicit these performance-enhancing benefits.

So, now you have the perfect excuse to indulge your chocolate craving. To avoid weight gain, stick to no more than 40g, roughly 2 – 3 squares, a day, and opt for dark chocolate that’s at least 70% cocoa solids to get the highest concentration of flavanols. Alternatively a spoonful of cocoa powder (I’m loving Aduna Super-cacao powder at the moment) whisked into hot milk works well!

If you enjoyed this post and want to find out more about sport and exercise nutrition, then read the new edition of my book:

Food For Fitness

A sports nutrition guide and recipe book rolled into one, Food for Fitness dispels popular myths and gives you the tools you need to reach your maximum performance. It is the ultimate resource for anyone who is serious about sport or fitness. Now in its fourth edition, this bestselling book has been updated to include the very latest nutrition research for exercise and performance, and is packed with easy, delicious and nutritious recipes, snacks and helpful new menu plans.