Does Drinking Beetroot Juice Before a Race Actually Make You Faster?

Beetroot juice keeps showing up in race-day chatter, and for once the hype has decent science under it. The mechanism is dietary nitrate, which your body converts to nitrite and then to nitric oxide, improving blood flow and lowering the oxygen cost of submaximal exercise. A well-cited meta-analysis in the European Journal of Applied Physiology found that nitrate supplementation improved time-to-exhaustion and, more modestly, time-trial performance (see [1]). The effect is real, but it is small, and it does not land equally on every runner.

Here is the part most people miss. The benefit shows up most clearly in recreational and moderately trained athletes, and it shrinks as you get fitter. Highly trained endurance athletes already have a robust nitric-oxide system from years of aerobic work, so there is less to gain (see [2]). If you are eight weeks into a couch-to-5K, a nitrate boost might shave a meaningful sliver off your effort. If you are chasing a Boston qualifier off 60-mile weeks, expect closer to nothing. That is not a reason to skip it, but it is a reason to keep your expectations honest.