This tonic turns your urine and stool bright red, but if you can get past those startling—albeit harmless—side effects, beetroot juice may be one of nature’s most powerful performance enhancers, says Allen Lim, Ph.D., founder of Skratch Labs, an “active nourishment company” famous for helping train professional cyclists like Taylor Phinney
Athletes Lim coaches have been drinking the juice for years. But until now, dosing has been a problem—nobody knew exactly how many beets you needed to drink to see a boost. Now, a study in the Journal of Applied Physiology suggests that drinking between about 280 ml—about one glass—of the juice is enough to yield considerable performance gains.
Researchers believe that nitrates in the juice raise your body’s efficiency, allowing you to put more force on the pedals and less energy into producing heat. The specifics: Beetroot juice is high in nitrates, which your body converts into nitric oxide, a gas that widens your blood vessels and ups the oxygen available to your muscles.
How big a difference does it make? Cyclists on the mix were able ride at a set intensity between 12 to 14 percent longer than those who went without the drink. The findings aren’t an anomaly, either. Prior research shows that cyclists who drank half a liter of the juice for six days clocked in 45 seconds faster over a 10-mile course, a huge gain in a sport where the difference between winning and losing is often just a tire’s width.
Lim suggests mixing around eight ounces of the juice with an equal-parts mixture of orange, carrot, and pineapple to cut through the taste. Try it in training by loading up with a glass a day, for one week. Some research suggests that beetroot juice can lower blood pressure, so avoid this elixir if you’re prone to getting lightheaded or start noticing those symptoms while loading, says Stacy Sims, Ph.D., co-founder of Osmo Nutrition.