For years, beetroot juice has carried the promise of an edge — a natural, nitrate-rich shortcut to faster times that endurance athletes swore by. When researchers gathered twelve studies and pooled the results from 120 competitive swimmers, however, the evidence declined to confirm the legend. The meta-analysis, published in September 2026, found no meaningful improvement in race times or physiological stress markers, leaving open the older, quieter truth that performance in the water still answers most faithfully to training and technique.
Beetroot juice eases swimming effort but doesn't boost performance
It made swimming feel easier, but not faster.
Mark
So beetroot juice doesn't make swimmers faster. But it does make swimming feel easier. Isn't that worth something?
Mimi
It's worth asking about, but the effect was small and inconsistent. Some studies showed it, others didn't. And here's the thing—if it made swimming feel easier without actually improving performance, that's almost a red flag. It suggests the perception might not be tracking reality.
Luke
Right. And we should be clear: this is nine studies, 120 swimmers total. That's not a huge sample. The researchers themselves said the certainty of evidence is low. They couldn't rule out a small real effect; they just didn't find one.
Mark
Why does it work for runners and cyclists but not swimmers?
Mimi
That's the unanswered question. Nitrates improve oxygen efficiency, which helps in endurance sports. But swimming is different—it's explosive, it's anaerobic, the biomechanics are unique. The physiology might just not respond the same way.
Luke
And most of the prior research on nitrates was done in cycling and running. Swimming research is scarce. So we're applying findings from one sport to another without really understanding if the mechanism translates.
Mark
What would it take to actually know?
Mimi
Larger trials, more diverse swimmers, different dosing strategies. The researchers were pretty clear about that. They want to see better-controlled studies before anyone recommends this as a standard supplement.
Luke
And they want to explore other outcomes too—not just time trials, but other physiological markers that might show a benefit even if race times don't improve. Right now, the practical answer is: it doesn't help you swim faster.
Mark
So swimmers should just skip it?
Mimi
Based on this evidence, yes. There's no performance gain. The perceived exertion reduction is small and unreliable. It's not worth the cost or the uncertainty.
Luke
Unless you're in a study. Then it's worth knowing about, because this is clearly not the final word on the topic.
The Pulse
- Beetroot juice arrived in swimming with a reputation built in cycling and running, where nitrate supplementation had shown real, measurable gains — but the pool proved a different arena entirely.
- Across sprint, prolonged sprint, and middle-distance events, 120 competitive swimmers showed no faster times after supplementation, and their post-race blood lactate levels were identical to those on placebo.
- One modest signal survived the analysis: swimmers reported feeling like they were working less hard, yet this reduction in perceived exertion never translated into the clock moving in their favor.
- The certainty of the evidence was graded low — small sample sizes, inconsistent protocols, and design flaws in half the studies mean the question is not closed, only unanswered at scale.
- Researchers are calling for larger, more rigorous trials with diverse swimmer populations and varied dosing strategies before beetroot juice can be written off or written in as a legitimate swimming ergogenic.
For years, beetroot juice has carried the promise of an edge — a natural, nitrate-rich shortcut to faster times that endurance athletes swore by. When researchers gathered twelve studies and pooled the results from 120 competitive swimmers, however, the evidence declined to confirm the legend. The meta-analysis, published in September 2026, found no meaningful improvement in race times or physiological stress markers, leaving open the older, quieter truth that performance in the water still answers most faithfully to training and technique.
Beetroot juice built its reputation in endurance sport on solid ground. Cyclists and runners documented real gains from nitrate-rich supplements, which raise nitric oxide in the bloodstream and help muscles use oxygen more efficiently. The logic seemed transferable to swimming, and so researchers set out to test it — pooling data from twelve studies to ask whether the supplement could move the clock for competitive swimmers.
Nine of those studies, covering 120 swimmers from moderately trained university athletes to elite competitors, provided data clean enough for statistical analysis. The events ranged from 50-meter sprints to middle-distance races, with swimmers tested in randomized crossover designs that had each athlete compete under both supplemented and placebo conditions.
The answer was unambiguous in what it failed to find. Beetroot juice did not improve swimming time-trial performance at any distance — not in explosive sprints under thirty seconds, not in prolonged efforts stretching to ninety, not in middle-distance races beyond. Post-exercise blood lactate, a reliable marker of how hard the body worked, showed no difference either. The supplement appeared to change neither the physiological cost of racing nor the capacity to recover from it.
One thread of evidence ran slightly warmer. Across seven studies, swimmers reported lower perceived exertion after supplementation — they felt like they were working less hard. But the effect was modest, inconsistent across studies, and crucially, it never produced faster times. The sensation of ease did not become speed.
The researchers were candid about the limits of their own analysis. Half the underlying studies carried methodological concerns or outright design flaws, sample sizes were small, and protocols varied enough to complicate comparison. They could not rule out that a genuine but small performance effect exists and simply went undetected for lack of statistical power.
Why swimming resists what cycling and running have embraced remains an open question. The physiology differs — swimming leans heavily on anaerobic power and explosive mechanics, domains where oxygen-efficiency gains may offer less leverage. The biomechanics of moving through water impose constraints that land-based endurance research was never designed to address.
For now, the researchers stopped short of dismissing beetroot juice entirely, but they did not recommend it either. They called instead for larger, well-controlled trials exploring different doses and more diverse swimmer populations. Until that evidence arrives, the fundamentals — training, technique, and time in the water — remain the most reliable path to the other side of the wall.
Beetroot juice has built a reputation in endurance sports as a performance enhancer. Cyclists and runners have reported measurable gains from nitrate-rich supplements, which work by increasing nitric oxide in the bloodstream and improving how efficiently muscles use oxygen. The logic seemed sound enough to test in swimming. But when researchers pooled data from twelve studies examining whether beetroot juice or dietary nitrate supplements could boost swimmers' times, the results told a different story.
Nine of those studies, involving 120 competitive swimmers, provided data robust enough for statistical analysis. The swimmers ranged from moderately trained athletes to elite competitors, mostly young adults training at university level. Most protocols focused on short-distance races—50 to 100 meters—though one unusual study assessed a 168-meter backstroke time trial, a distance chosen because of pool constraints rather than scientific design. The researchers compared swimmers who took beetroot juice or nitrate supplements against those given placebos, using randomized crossover designs where each swimmer tried both conditions.
The headline finding was straightforward: supplementation did not significantly improve swimming time-trial performance. This held true across sprint events lasting thirty seconds or less, prolonged sprints stretching to ninety seconds, and middle-distance races beyond that threshold. The pooled analysis of 120 swimmers showed no meaningful difference in race times. Post-exercise blood lactate concentrations—a marker of metabolic demand—also showed no difference between supplemented and placebo conditions, suggesting the supplement neither reduced the physiological stress of racing nor enhanced recovery capacity.
There was one small positive signal. When researchers examined perceived exertion across seven studies involving 100 swimmers, they found a statistically significant reduction in how hard the swimming felt after supplementation. Swimmers rated their effort lower on the Borg scale after taking beetroot juice or nitrates compared to placebo. But this effect was modest, and it varied considerably from study to study. More importantly, it did not translate into faster times. Swimmers felt like they were working less hard, but they were not actually swimming faster.
The researchers graded the certainty of their evidence as low, primarily because of methodological concerns in the underlying studies and imprecision in the pooled estimates. Three studies were rated as having low risk of bias, six had some concerns, and three carried high risk because of design flaws. The total number of available studies was small, sample sizes were generally modest, and the protocols varied enough to limit how broadly the findings could be applied. The authors could not assess publication bias because there were too few studies to detect it reliably.
Why might beetroot juice work for cyclists and runners but not swimmers? The source material offers no definitive answer, though it notes that most prior research on nitrate supplementation has focused on cycling and running rather than swimming-specific outcomes. The physiology differs. Swimming demands explosive power and anaerobic effort in ways that may not respond to the oxygen-efficiency gains nitrates provide. The pool environment, water resistance, and the biomechanics of propulsion through water may simply operate under different constraints than land-based endurance sports.
The researchers stopped short of declaring beetroot juice useless for swimmers. They noted that the limited evidence could not rule out a small performance effect—the studies may simply have lacked the statistical power to detect one. But they did not recommend beetroot juice as a general ergogenic aid for competitive swimming based on current evidence. They called instead for larger, well-controlled trials across more diverse swimmer populations, exploring different supplementation strategies, dose-response relationships, and other physiological outcomes that might reveal benefits the current research missed. Until then, swimmers chasing performance gains would be better served by focusing on training, technique, and the fundamentals that have always mattered.
Notable Quotes
Current evidence does not show a meaningful improvement in swimming performance or a change in post-exercise blood lactate concentrations in trained swimmers.— Study authors, published in Scientific Reports
A small reduction in RPE was observed, but its consistency and practical relevance remain uncertain, and it did not translate into performance gains.— Study authors
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