Supplementing with Nitrates to Enhance High-Intensity Exercise Performance
The world of sports supplements (really supplements in general) is riddled with imposters, plagued by unverifiable claims, and lacking in regulation. For this reason, there are generally a lot of supplements available, but only a few that really show any efficacy in doing what they claim to do or containing what they claim to contain. For those who may be curious, the supplements with the most evidence to support their use include caffeine, creatine, beta-alanine, and sodium bicarbonate.
I’ll add another to that list — nitrates and nitrites. These aren’t really “supplements” — they’re found in leafy greens and beets, among other sources. However, nitrate/nitrite-containing products like concentrated beetroot juice and beet juice “shots” are available for anyone to buy and ingest and have been used in many research studies for their potential health and performance-enhancing effects.
The effects of nitrates/nitrites on cardiovascular health and performance are large and well-evidenced. This is because nitrates/nitrites, once ingested, get metabolized into a molecule called nitric oxide (NO). NO has many beneficial effects including promoting blood vessel relaxation and increasing blood flow delivery to our muscles. This is why research on “supplements” that boost NO is so popular. This in addition to the fact that nitrates/nitrites are cheap and easy to consume in this form or by eating vegetables which contain them.
For exercise and sports performance, nitrates/nitrites could provide a real benefit to recreational and high-level athletes. As a “risk-free” dietary supplement, it is worthwhile to understand the effects that ingesting nitrates/nitrites could have for physical performance, most of which are hypothesized to come from enhancing oxygen delivery to working muscles.
A recently published study that appeared in the journal Current Research in Physiology investigated whether a supplement containing nitrates/nitrites from beets could enhance high-intensity exercise performance, which could provide some rationale for using NO-boosting supplements as a “pre workout” or as a daily ergogenic supplement.
Brief study methods
This study was conducted in trained male cyclists. In a double-blind crossover study, participants completed two interventions in which they received either a placebo or a nitric oxide-enhancing (NOE) supplement.
Supplement used: Humann Beet Elite
At the start of each trial period, participants consumed the placebo or NOE supplement for 2 days and then underwent a lactate threshold test. They then supplemented for 3 more days before undergoing a high-intensity interval training (HIIT) session.
The researchers were interested in outcomes including power output (Watts) at lactate threshold and the total time to exhaustion, work output, energy expenditure, distance traveled, and intervals completed during the HIIT session at the end of the supplementation week. Levels of muscle oxygenation and hemoglobin saturation were also measured during exercise.
- The NOE supplement increased lactate threshold power by 17.2% vs. the placebo
- The NOE supplement increased HIIT performance by improving time to exhaustion, number of intervals completed, distance traveled, and total energy expended
- The NOE supplement increased muscle oxygenation and hemoglobin saturation during HIIT work and rest intervals compared to the placebo
I’m a bit surprised that the NOE supplement was able to increase performance in already well-trained, highly fit athletes. A lot of the nitrate/nitrite supplement literature is conducted in clinical populations such as those with arterial disease, heart failure, or other cardiovascular complication in which blood flow and oxygen delivery may be impaired. In such cases, elevating levels of NO would improve exercise tolerance and performance by enhancing oxygen delivery. The fact that such a supplement also increases performance and muscle oxygenation in trained athletes (who we might assume have adequate levels of NO) is promising while also a bit unexpected.
There are several reasons to begin supplementing with nitrates/nitrites including the well-known cardiovascular health benefits and the fact that you might also be able to increase your performance in the gym or at your local road race. It’s an extremely low-risk supplement. Whether using the product in this study, one of the many other beet-containing products available, or through daily consumption of leafy green vegetables and beets, getting your nitrates/nitrites can help your heart and your 5k PR to flourish.