Nitric oxide (NO) boosting supplements improve muscle blood flow, glucose uptake, mitochondrial energy production, and contraction efficiency during exercise. Hence, why every major supplement company includes “NO boosters” in their preworkout formulations. The most popular NO boosters tend to include sources of nitrates (like beetroot powder) or L-citrulline to pump up NO levels; however recent research illustrates that there may be a tastier option— DARK CHOCOLATE! The abundant bioactive flavanols, found within the cocoa that makes chocolate dark, promote increased NO bioavailability in the body.
In a study published in the Journal of the International Society of Sports Nutrition, nine moderately-trained males underwent baseline testing: a cycling VO2max test immediately followed by cycling at 80% of max for 20-min, and then an “all out” sprint for a 2-min. Using a randomized crossover design, participants then consumed either 40 g of dark chocolate or white chocolate daily (for 2 weeks), and then performed 2 more identical cycling tests (2 weeks apart).
Overall, when participants consumed dark chocolate, they worked at 21% and 11% greater workloads (for a given level of oxygen consumption) compared to baseline and white chocolate conditions respectively. As well, dark chocolate consumption resulted in 17% and 13% greater distance covered during the “all out” sprint cycling time trial compared to baseline and white chocolate conditions respectively.
ACTION POINT: This study illustrates that daily dark chocolate consumption can improve exercise endurance and performance. To reap these delicious benefits, add a 1/4 cup of cocoa or cocao powder (70% cocoa or better) to your preworkout protein shake. For the sake of calories, we suggest using pure organic cocoa or cocao powder over eating chocolate bars for NO boosting.
Reference: Patel RK, Brouner J, Spendiff O. Dark chocolate supplementation reduces the oxygen cost of moderate intensity cycling. J Int Soc Sports Nutr. 2015 Dec 15;12:47.