Physical Performance Following Multiday Beetroot Juice Supplementation in Female Basketball Players: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study
试验速览
- 阶段
- 不适用
- 状态
- Enrolling By Invitation
- 入组人数
- 16
- 试验地点
- 1
- 主要终点
- Changes in maximal isometric handgrip strength (N)
研究概览
简要总结
A randomized, double-blind, placebo-controlled study investigates the effects of 5 days of nitrate-rich beetroot juice supplementation (70 mL·day-¹; 6.4 mmol NO₃-·day-¹) on physical performance in female basketball players. Performance will be evaluated using jump, 30-m sprint, agility, and isometric mid-thigh pull (IMTP) tests, while RPE and potential side effects will be assessed through questionnaires. The study aims to address the limited evidence regarding the ergogenic effects of beetroot juice supplementation in female team-sport athletes.
详细描述
Although beetroot juice supplementation, primarily due to its high inorganic nitrate (NO₃-) content, has been associated with improvements in endurance and high-intensity intermittent exercise performance, its potential ergogenic effects in team sports remain unclear, particularly in female athletes. This knowledge gap is especially relevant in basketball, a sport characterized by repeated bouts of sprinting, jumping, accelerating, decelerating, and changing direction. Therefore, this randomized, double-blind, placebo-controlled study aimed to investigate the effects of 5 consecutive days of nitrate-rich beetroot juice supplementation (70 mL·day-¹, providing 6.4 mmol NO₃-·day-¹) on physical performance in female basketball players. Following the supplementation period, performance was assessed through jumping performance, 30-m sprint, agility, and isometric mid-thigh pull (IMTP) tests. Additionally, rating of perceived exertion (RPE) and potential side effects associated with beetroot juice supplementation were assessed using questionnaires.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
盲法说明
In addition to the participants, the investigators responsible for performance testing and data analysis will remain blinded to group allocation until completion of data collection and statistical analyses.
入排标准
- 年龄范围
- 18 Years 至 35 Years（Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Female basketball players aged 18-35 years.
- •Currently participating in natitional competitive basketball.
- •Able to complete all supplementation and testing procedures.
排除标准
- •Presence of any chronic disease or medical condition that could affect physical performance or interfere with the study procedures.
- •Presence of any injury during the month prior to the study that could limit participation in the physical performance tests.
- •Known intolerance or allergy to beetroot or other nitrate-rich vegetables (e.g., beetroot, lettuce).
- •Use of medications or dietary supplements that could potentially influence nitrate metabolism or physical performance during the study period.
研究组 & 干预措施
Experimental: Beetroot juice supplementation
Participants consumed one serving of 70 mL of nitrate-rich BJ (6.4 mmol of NO₃-; Beet-It-Pro Elite Shot, James White Drinks Ltd., Ipswich, UK) was administered daily for 5 consecutive days. On the final supplementation day, the placebo was consumed 3 h before the testing session
干预措施: Beetroot juice supplementation (Dietary Supplement)
Placebo supplementation
Participants consumed one 70-mL serving of nitrate-depleted beetroot juice placebo (0.04 mmol of NO₃-; Beet-It-Pro Elite Shot, James White Drinks Ltd., Ipswich, UK) daily for 5 consecutive days. On the final supplementation day, the placebo was consumed 3 h before the testing session.
干预措施: Placebo (Other)
结局指标
主要结局
Changes in maximal isometric handgrip strength (N)
时间窗: 1-week
Isometric Mid-Thigh Pull (IMTP): Lower-body maximal isometric strength will be assessed using the isometric mid-thigh pull (IMTP) performed on VALD ForceDecks force platforms (VALD Performance, Brisbane, Australia). Participants will adopt a standardized mid-thigh pull position with the knees and hips slightly flexed and will be instructed to pull against an immovable bar as hard and as fast as possible. Ground reaction force will be recorded by the force platforms throughout each maximal effort. Peak force will be expressed both as absolute force (N) and relative to body mass (N·kg-¹). Participants will perform maximal trials separated by an appropriate recovery period, and the best trial will be retained for analysis.
Changes in maximal jump height (cm)
时间窗: 1-week
Maximal Jump Height: Lower-body explosive performance will be assessed using the squat jump (SJ), countermovement jump (CMJ), and countermovement jump with arm swing (CMJ-AS). Jump performance will be measured using an OptoJump Next system (Microgate, Bolzano, Italy). Participants will perform maximal-effort trials for each jump condition following standardized instructions. Maximal jump height (cm) will be recorded for each jump type, and the best performance will be retained for analysis. Changes in maximal jump height following 5 days of supplementation will be compared between the nitrate-rich beetroot juice and placebo conditions.
Changes in sprint time (s)
时间窗: 1-week
Sprint performance will be assessed by measuring the time required to complete 10-m, 20-m, and 30-m sprints using Microgate photocell timing gates (Microgate, Bolzano, Italy). Participants will be instructed to sprint as fast as possible over the 30-m distance, with split times recorded at 10 m, 20 m, and 30 m. Sprint time will be recorded in seconds (s). Participants will perform maximal trials separated by an appropriate recovery period, and the best performance will be retained for analysis.
Changes in agility test (s)
时间窗: 1-week
Modified T-Test Performance: Change-of-direction performance will be assessed using the modified T-test, with completion time measured using Microgate photocell timing gates (Microgate, Bolzano, Italy). Participants will be instructed to complete the standardized course as quickly as possible, incorporating forward sprinting, lateral shuffling, and backward running. Completion time will be recorded in seconds (s). Participants will perform maximal trials separated by an appropriate recovery period, and the best performance will be retained for analysis.
次要结局
- Saliva NO3- and NO2- Measurements(1-week)
- Rating of percevied exertion (RPE) (measured using scale 6-20 points)(1-week)
- Side Effects Associated With Beetroot Juice Supplementation(1-week)