Faculty of Sport Sciences, Universidad Europea de Madrid, Madrid, Spain.
Faculty of Sport Sciences, University of Murcia, San Javier, Spain.
J Am Nutr Assoc. 2022 Jan;41(1):30-37. doi: 10.1080/07315724.2020.1835585. Epub 2020 Nov 12.
Beetroot juice is a source of dietary nitrate (NO-) recognized as a potential ergogenic aid to enhance tolerance during endurance exercise of submaximal-to-maximal intensity. However, little is known about the effects of beetroot juice on exercise performance in intermittent sports such as tennis. The present study aimed to determine the effect of acute beetroot juice supplementation on movement patterns during a competitive tennis match in professional players.In a double-blind and randomized experiment, nine professional tennis players performed two experimental trials 3h after ingesting either 70 mL of a commercially-available concentrated beetroot juice (6.4 mmol NO-) or placebo (0.005 mmol NO-). In each experimental trial, players completed a 3-set tennis match and two performance tests (i.e., serve speed and isometric handgrip strength) before and after the match. Match-play running performance was recorded using wearable GPS and accelerometer units.In comparison to the placebo trial, the acute beetroot juice supplementation did not modify any match-play running performance ( 0.178 to 0.997, = 0.01 to 0.42). Furthermore, beetroot juice supplementation did not alter the pre-to-post match change in serve speed ( = 0.663, = 0.03) or isometric handgrip strength ( = 0.219, = 0.18). The current results indicated that acute ingestion of a commercialized shot of nitrate-rich beetroot juice (70 mL containing 6.4 mmol of NO-) did not produce any performance benefit on tennis matchplay. Thus, acute beetroot juice supplementation seems an ergogenic aid with little value to enhance physical performance in professional tennis players.
甜菜根汁是膳食硝酸盐(NO-)的来源,被认为是一种潜在的促进耐力运动能力的辅助剂,可提高次最大至最大强度耐力运动的耐受性。然而,关于甜菜根汁对网球等间歇性运动的运动表现的影响知之甚少。本研究旨在确定急性甜菜根汁补充对职业网球运动员比赛中运动模式的影响。
在一项双盲、随机实验中,9 名职业网球运动员在摄入 70ml 市售浓缩甜菜根汁(6.4mmolNO-)或安慰剂(0.005mmolNO-)后 3 小时进行了两次实验。在每次实验中,运动员在比赛前后完成了 3 盘网球比赛和 2 项性能测试(即发球速度和等长握力)。比赛中运动员的跑动表现使用可穿戴 GPS 和加速度计单元进行记录。
与安慰剂试验相比,急性甜菜根汁补充并未改变任何比赛跑动表现(0.178 至 0.997,=0.01 至 0.42)。此外,甜菜根汁补充并未改变发球速度的比赛前后变化(=0.663,=0.03)或等长握力的比赛前后变化(=0.219,=0.18)。目前的结果表明,急性摄入商业化的富含硝酸盐的甜菜根汁(70ml 含 6.4mmolNO-)不会对网球比赛表现产生任何益处。因此,急性甜菜根汁补充似乎是一种对提高职业网球运动员身体表现几乎没有价值的促进耐力运动能力的辅助剂。