The Effect of Beetroot Powder on Exercise Performance in Competitive Swimmers
2026年6月19日 更新者：Aysun Köktürk Bayram、Halic University
Swimming requires high energy in a short time and involves overcoming water resistance. Besides regular training, swimmers use supplements to enhance performance, correct nutrient deficiencies, and speed recovery. The Australian Institute of Sport (AIS) classifies supplements by evidence level, with nitrate in Group A. Nitrate aids vasodilation and muscle performance via conversion to nitric oxide (NO).
About 25% of dietary nitrate converts to nitrite by oral bacteria, then to NO in the stomach-a valuable oxygen-independent pathway. NO improves exercise by enhancing oxygen efficiency, muscle contraction, and affecting type II fibers. Timing, dose, nitrate source, and individual traits influence its effect. Beetroot, rich in nitrate, is practical as juice for storage and consumption.
Beetroot gels and juices raise plasma nitrate 1-3 hours post-consumption, effective during 10-17 minute exercises. Some studies found no improvement in short-distance swimming, but others reported dose-dependent benefits. Meta-analyses recommend 5-14.9 mmol nitrate ≥150 minutes before acute exercise, and 5-9.9 mmol for chronic intake. Highly trained athletes may need ≥6-8 mmol NO₃-.
JECFA and the European Commission set acceptable daily intake (ADI) at 0-3.7 mg/kg body weight nitrate ion, safe for all ages.
No long-term, controlled studies exist on beetroot powder's effect in swimmers. To address this, a randomized, placebo-controlled, triple-blind crossover study was designed to evaluate beetroot powder supplementation's impact on competitive swimmers' performance, potentially contributing valuable knowledge.
研究概览
详细说明
- Study Design and Participants: This study employed a randomized, double-blind, placebo-controlled crossover design to investigate the effects of beetroot supplementation. Based on a power analysis conducted with a 5% error level and a statistical power of 0.95, a sample size of 36 participants was determined to be sufficient. The study was conducted over a one-year period at the Galatasaray Swimming Club following approval from the institutional ethics committee, and all participants provided written informed consent. Inclusion criteria required voluntary participation with parental consent, an age range of 18-24 years, participation in a structured training program for at least 18 hours per week, no history of chronic disease, no current use of sports or food supplements/medications, and no adherence to a special diet. Conversely, exclusion criteria included irregular training attendance, the presence of chronic diseases, and a failure to cease the use of food supplements one week prior to the study.
- Product Development and Standardization: Three types of beetroot powder were selected from the Turkish market and analyzed by a laboratory accredited under the TURKAK TS EN ISO/IEC 17025:2017 standard, utilizing the HPLC-DAD method in accordance with NMKL No. 165. Based on these analyses, 1.5 g of beetroot powder, corresponding to a 10 mmol nitrate intervention, was used for product development at the Haliç University Nutrition Principles Laboratory. A base mixture of water, gelatin, pectin, starch, and stevia was heated to 85-90°C for homogenization and cooled to 55-60°C. The intervention product contained 1.5 g of beetroot powder, while the placebo product included food coloring to match the visual characteristics of the intervention. Products were prepared 24 hours before each session, stored in opaque, food-safe packaging at 0-4°C, and coded by an independent researcher using a random number generator to ensure triple-blind conditions.
- Experimental Procedure and Controls: Participants were instructed to maintain their habitual dietary intake throughout the study and were provided with a list of nitrate-rich foods to avoid. To prevent interference with oral nitrate-to-nitrite reduction, participants were strictly instructed to abstain from mouthwash, chewing gum, sweets, stimulants, and alcohol on all intervention days. The study consisted of five visits. Visit 1 involved providing study information and obtaining informed consent, while Visit 2 included baseline anthropometric assessments and randomization. Visit 3 involved data collection, including food record retrieval, a standardized warm-up, a 200-m freestyle performance test, and post-test measurements of blood lactate, heart rate, and fatigue. A two-week washout period was implemented between intervention phases to eliminate potential carry-over effects, followed by Visits 4 and 5, where the crossover intervention was conducted by repeating the established testing protocols with the alternative condition.
- Data Collection: Sociodemographic and lifestyle data, including age, sex, education, nutritional habits, and training characteristics, were recorded. Anthropometric measurements included body composition via bioelectrical impedance analysis, height, BMI, and hand grip strength measured by a digital dynamometer. Performance was assessed through a 200-m maximum-effort freestyle swimming test. Physiological assessments included fingertip blood lactate concentration and heart rate (resting, maximum, and average). Finally, subjective fatigue was evaluated using the Perceived Physical and Cognitive Fatigue Scale and the Visual Analog Scale (VAS).
研究类型
介入性
注册 (实际的)
21
阶段
- 不适用
联系人和位置
本节提供了进行研究的人员的详细联系信息，以及有关进行该研究的地点的信息。
学习地点
-
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Kartal
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Istanbul、Kartal、土耳其（türkiye）
- Kartal Kosuyolu Yuksek Ihtisas EAH
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-
参与标准
研究人员寻找符合特定描述的人，称为资格标准。这些标准的一些例子是一个人的一般健康状况或先前的治疗。
资格标准
适合学习的年龄
- 成人
接受健康志愿者
是的
描述
Inclusion Criteria:
- Voluntary participation with parental consent
- Age range: 18-24 years
- Participation in a training program for at least 18 hours per week
- No history of chronic disease
- Not currently using any sports supplements, food supplements, or medications
- Not following a special diet
Exclusion Criteria:
- Irregular training participation
- Presence of chronic diseases
- Failure to cease the use of food supplements one week prior to the study
学习计划
本节提供研究计划的详细信息，包括研究的设计方式和研究的衡量标准。
研究是如何设计的？
设计细节
- 主要用途：支持治疗
- 分配：随机化
- 介入模型：交叉作业
- 屏蔽：四人间
武器和干预
参与者组/臂 |
干预/治疗 |
|---|---|
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实验性的：Beetroot then Placebo
Participants in this arm will first receive 1,5 grams of beetroot powder contain jelly candy daily for 3 consecutive days.
After a 14-day washout period, they will receive placebo jelly candy daily for 3 consecutive days.
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1.5 g of beetroot powder (equivalent to 10 mmol nitrate) administered as a jelly candy.
Color-matched, nitrate-free jelly candy.
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安慰剂比较：Placebo then Beetroot
Participants in this arm will first receive placebo jelly candy daily for 3 consecutive days.
After a 14-day washout period, they will receive 1,5 grams of beetroot powder contain jelly candy daily for 3 consecutive days.
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1.5 g of beetroot powder (equivalent to 10 mmol nitrate) administered as a jelly candy.
Color-matched, nitrate-free jelly candy.
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研究衡量的是什么？
主要结果指标
结果测量 |
措施说明 |
大体时间 |
|---|---|---|
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Change in 200-meter swim performance time
大体时间：On the 3rd day of each 3-day intervention period (after beetroot or placebo supplementation).
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The duration (in seconds) required for the participant to complete a 200-meter freestyle swim, measured using a Seiko stopwatch.
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On the 3rd day of each 3-day intervention period (after beetroot or placebo supplementation).
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Blood lactate concentration
大体时间：Immediately post-exercise on the 3rd day of each 3-day intervention period (after beetroot or placebo supplementation).
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Blood lactate levels (mmol/L) measured from capillary blood samples collected 3 minutes after completion of 200-meter swim test.
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Immediately post-exercise on the 3rd day of each 3-day intervention period (after beetroot or placebo supplementation).
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次要结果测量
结果测量 |
措施说明 |
大体时间 |
|---|---|---|
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Visual Analog Scale (VAS) for Perceived Fatigue
大体时间：On the 3rd day of each 3-day intervention period (after beetroot or placebo supplementation).
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Participant's self-reported fatigue level assessed using a 10-cm visual analog scale, ranging from 0 (no fatigue) to 10 (extreme fatigue), completed immediately after the swim test.
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On the 3rd day of each 3-day intervention period (after beetroot or placebo supplementation).
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Heart Rate Change
大体时间：On the 3rd day of each 3-day intervention period (after beetroot or placebo supplementation).
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Maximum heart rate during the 200m swim, heart rate at 1 minute post-performance, and mean heart rate during the test, recorded using a Polar sports watch with an integrated wrist-based optical heart rate monitor.
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On the 3rd day of each 3-day intervention period (after beetroot or placebo supplementation).
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Change in Perceived Physical and Cognitive Fatigue Scale (AFBYÖ) Scores
大体时间：On the 3rd day of each 3-day intervention period (after beetroot or placebo supplementation).
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The 19-item Perceived Physical and Cognitive Fatigue Scale (PPCFS) is a 5-point Likert-type instrument used to assess athletes' perceived fatigue levels after each training session.
The scale consists of two subscales: the Perceived Physical Fatigue (PPF) subscale, which includes the first 8 items with a total score range of 8 to 40, and the Perceived Cognitive Fatigue (PCF) subscale, which includes the remaining 11 items with a total score range of 11 to 55.
The total score of the scale ranges from 19 to 95, where higher scores in either the subscales or the total score indicate increased levels of physical and cognitive fatigue, respectively.
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On the 3rd day of each 3-day intervention period (after beetroot or placebo supplementation).
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Daily Energy and Nutrient Intake
大体时间：Collected during the 24-hour period prior to the 3rd day of each 3-day intervention period (both beetroot or placebo supplementation).
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Dietary intake was monitored through 24-hour dietary records kept by participants for 24 hours prior to each measurement day.
Ingredient quantities for composite dishes were calculated using the "Standard Food Recipes" manual.
Subsequently, total daily energy and nutrient intakes were analyzed and quantified using the Nutrition Information System (BeBİS) software.
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Collected during the 24-hour period prior to the 3rd day of each 3-day intervention period (both beetroot or placebo supplementation).
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合作者和调查者
在这里您可以找到参与这项研究的人员和组织。
出版物和有用的链接
负责输入研究信息的人员自愿提供这些出版物。这些可能与研究有关。
研究记录日期
这些日期跟踪向 ClinicalTrials.gov 提交研究记录和摘要结果的进度。研究记录和报告的结果由国家医学图书馆 (NLM) 审查，以确保它们在发布到公共网站之前符合特定的质量控制标准。
研究主要日期
学习开始 (实际的)
2025年12月22日
初级完成 (实际的)
2026年5月22日
研究完成 (实际的)
2026年6月1日
研究注册日期
首次提交
2026年6月16日
首先提交符合 QC 标准的
2026年6月19日
首次发布 (实际的)
2026年6月23日
研究记录更新
最后更新发布 (实际的)
2026年6月23日
上次提交的符合 QC 标准的更新
2026年6月19日
最后验证
2025年5月1日
更多信息
与本研究相关的术语
其他研究编号
- 2025-08/318
计划个人参与者数据 (IPD)
计划共享个人参与者数据 (IPD)？
不
IPD 计划说明
Individual participant data (IPD) will not be shared due to concerns regarding participant confidentiality and the small sample size, which may increase the risk of re-identification.
药物和器械信息、研究文件
研究美国 FDA 监管的药品
不
研究美国 FDA 监管的设备产品
不
此信息直接从 clinicaltrials.gov 网站检索，没有任何更改。如果您有任何更改、删除或更新研究详细信息的请求，请联系 register@clinicaltrials.gov. clinicaltrials.gov 上实施更改，我们的网站上也会自动更新.