For access to all of our training, gear, and race coverage, plus exclusive training plans, FinisherPix photos, event discounts, and GPS apps, sign up for Outside+.
Consumption of dark chocolate has shown to offer boost in fitness in studies on mice.
For those who worry that fitness requires nutritional denial, there is good news, with caveats. Auspicious new science suggests that chocolate can have a surprisingly large effect on the body’s response to exercise, although not in the ways that many of us might expect, and certainly not at the dosages most might hope for.
Researchers have known for some time that chocolate has healthful effects, and recent epidemiological studies have shown that people who regularly indulge in moderate amounts of dark chocolate are less likely to develop high blood pressure or heart disease or suffer strokes. But chocolate’s potential role in exercise performance had not been studied, or probably even much considered, until scientists at the University of California, San Diego, and other institutions gave middle-aged, sedentary male mice a purified form of cacao’s primary nutritional ingredient, known as epicatechin, and had the mice work out. Epicatechin is a flavonol, a class of molecules that are thought to have widespread effects on the body.
Exactly how epicatechin intensified the mouse muscles’ response to exercise is not yet known, but “it seems likely that muscle cells contain specific receptors for epicatechin,” said Dr. Francisco Villarreal, a professor of medicine at the University of California, San Diego, and one of the authors of the study, which was published last week in The Journal of Physiology. Epicatechin binds to the receptors and “induces an integrated response that includes structural and metabolic changes in skeletal and cardiac muscles resulting in greater endurance capacity,” the study concluded.
Read more: The New York Times