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Beetroot juice (BRJ) has been proposed as an ergogenic aid due to its high nitrate content, yet evidence from field-based studies in elite swimmers remains limited. This study investigated the acute effects of concentrated BRJ ingestion on performance and physiological responses during repeated maximal 200-m front-crawl efforts in elite male swimmers. Twelve elite swimmers (age: 20 ± 2 years, body fat: 7.1% ± 2.5%, 200-m personal best: 115.7 ± 3.4 s) completed a randomized, double-blind, counterbalanced trial. Participants consumed either 140 ml of concentrated BRJ (Beet It Sport) or a custom-made, nitrate-depleted placebo (PL) matched for sensory characteristics, 2 hr before performing two maximal 200-m front-crawl time trials, separated by 60 min of passive recovery. Blood samples were collected upon arrival and immediately after each time trials, and 200-m completion time, blood lactate concentrations, and ratings of perceived exertion were recorded. No significant differences were observed in completion time for either the first (PL: 116.7 ± 3.0 vs. BRJ: 117.2 ± 3.1 s, p =.19) or the second 200-m time trial (PL: 117.8 ± 2.6 vs. BRJ: 117.8 ± 3.3 s, p =.98), nor in the change between trials (PL: 1.1 ± 1.5 vs. BRJ: 0.5 ± 1.3 s, p =.40). Likewise, lactate concentrations and ratings of perceived exertion values did not differ between conditions (p >.05). In conclusion, acute BRJ supplementation did not enhance 200-m front-crawl performance, lactate responses, or perceived exertion in elite swimmers under competition-like conditions. Elite swimmers are always looking for safe ways to boost their speed and endurance in races, especially events like the 200-m front crawl that mix high-speed bursts and sustained effort. One popular idea is drinking concentrated beetroot juice, which is rich in nitrates. Nitrates are natural compounds from the beetroot plant that can help widen blood vessels, improve muscle oxygen use, and possibly speed up recovery between races. This study tested whether an acute dose of beetroot juice taken 2 hr before swimming could make top-level male swimmers faster or feel less tired during two back-to-back 200-m front crawl time trials, mimicking the demands of real competitions where athletes race multiple times with about an hour's rest in between. The researchers recruited 12 elite male swimmers, who compete at national and international levels—their personal best times in the 200-m placed them in the top 10%–12% worldwide. These athletes had low body fat (∼7%) and swam high weekly volumes (>30 km), making them a tough group to improve as they are already highly optimized. The experiment used a strict setup: a randomized, double-blind, crossover design where each swimmer tried both the beetroot juice (140 ml of Beet It Sport, containing 8 mmol nitrates) and a placebo drink that looked and tasted similar and had similar calories and nutrients but no nitrates. They drank it after fasting, did a standard warm-up, and then swam two all-out 200-m front crawls from the blocks, with 60 min of rest (light stretching only) between them. Researchers measured swim times (using stopwatches by two timers), blood lactate levels (a marker of muscle fatigue from fingertip pricks), and how hard the effort felt (using a simple 0–10 scale). They also tracked TNOx in blood serum to confirm that the juice raised nitrate levels as expected. Swimmers avoided nitrate-rich foods and supplements for days before, followed the same diet and training, and tested at the same time of day in a controlled pool. The beetroot juice worked as planned: it spiked blood nitrate–nitrite levels over 10 times higher than placebo 2 and 3 hr later, proving good absorption. However, it did not improve swim times; the first 200-m averaged 117 s for both drinks, and the second was identical at 117.8 s, with no meaningful slowdown between races either (about 0.5–1 s slower, typical fatigue). Blood lactate rose similarly after each swim (11–13 mmol/L, high effort indicator), and swimmers rated the effort the same (around 8/10 postswim). Statistics confirmed no differences, even accounting for small elite-level changes that matter in races won by 10ths of seconds. These results add to mixed evidence: although beetroot helps some runners or cyclists (especially less-trained ones) by lowering oxygen needs and aiding blood flow, it often fails in swimming, particularly for elite athletes whose bodies are already super efficient. Possible reasons include needing longer supplementation (days/weeks) for muscle changes or elites having less room to gain from nitrates as their oxygen delivery and muscle power are near perfect. Strengths include real-world testing on true elite swimmers, blinded setup, and competition-like repeats, but limits are the single dose, all-male group; manual timing (less precise than electronics); and no direct muscle oxygen measures. Overall, this suggests a beetroot shot will not give elite swimmers an edge in 200-m repeats, but small time differences could still matter competitively. Coaches might test individuals or try longer protocols. Future work could involve women, chronic use, or tech like oxygen sensors for deeper insights into why nitrates do not always translate to faster swims. [ABSTRACT FROM AUTHOR] |