Herrera-Amante Carlos Abraham, García-Zepeda Gustavo, García-Zepeda Carlos Eduardo, Yáñez-Sepúlveda Rodrigo, Clemente-Suárez Vicente Javier, López-Gil José Francisco, Octavio Ramos-García César
Nutritional Assessment and Nutritional Care Laboratory (LECEN), Division of Health Sciences, Tonalá University Center, University of Guadalajara, Tonalá, Mexico.
Research Division, Ibero-American Institute of Sports Sciences and Human Movement (IICDEM), Guadalajara, Mexico.
Front Nutr. 2025 Aug 13;12:1630462. doi: 10.3389/fnut.2025.1630462. eCollection 2025.
Endurance athletes experience significant water loss during exercise, which can impair performance and increase the risk of dehydration. Glycerol hyperhydration has been explored as a strategy to enhance pre-exercise hydration, particularly when fluid intake opportunities are limited. This study aimed to evaluate the effects of glycerol hyperhydration on running economy (RE) in trained runners.
A randomized crossover clinical trial was conducted with 30 trained runners (15 men, 15 women) across three sessions. In the first session, peak oxygen uptake (VOpeak) was determined to establish individualized running speeds for the subsequent tests. In the second and third sessions, participants performed submaximal running tests under two conditions: euhydration (control) and glycerol-induced hyperhydration. The glycerol protocol consisted of ingesting 1.2 g/kg body mass of glycerol diluted in 22 mL/kg of water, 120 min before exercise. The assessed variables included caloric cost unit (CCU), oxygen cost unit (OCU), heart rate (HR), body temperature (BT), and rating of perceived exertion (RPE). Effect sizes were calculated using standardized mean differences (Cohen's ).
Glycerol supplementation significantly improved running economy, reducing CCU ( = 0.025, d = 0.43), OCU ( = 0.011, r = 0.46), HR ( = 0.029, d = 0.42), and RPE ( = 0.003, d = 0.60). Although BT showed a slight decrease ( = 0.053, d = 0.37), it did not reach statistical significance, suggesting a trend toward improved thermoregulation.
These findings indicate that glycerol supplementation enhances key metabolic and physiological factors associated with running economy, including CCU, OCU, cardiovascular responses, and perceived exertion in trained runners.
https://clinicaltrials.gov, identifier: NCT06818253.
耐力运动员在运动过程中会出现大量水分流失，这可能会影响运动表现并增加脱水风险。甘油超量补水已被探索作为一种增强运动前补水的策略，尤其是在液体摄入机会有限时。本研究旨在评估甘油超量补水对训练有素的跑步者跑步经济性（RE）的影响。
对30名训练有素的跑步者（15名男性，15名女性）进行了一项随机交叉临床试验，共三个阶段。在第一阶段，测定峰值摄氧量（VOpeak），以确定后续测试的个性化跑步速度。在第二和第三阶段，参与者在两种条件下进行次最大强度跑步测试：正常补水（对照）和甘油诱导的超量补水。甘油方案包括在运动前120分钟摄入1.2克/千克体重的甘油，用22毫升/千克的水稀释。评估的变量包括热量消耗单位（CCU）、氧气消耗单位（OCU）、心率（HR）、体温（BT）和主观用力程度分级（RPE）。效应量使用标准化平均差（Cohen's ）计算。
补充甘油显著改善了跑步经济性，降低了CCU（=0.025，d=0.43）、OCU（=0.011，r=0.46）、HR（=0.029，d=0.42）和RPE（=0.003，d=0.60）。虽然BT略有下降（=0.053，d=0.37），但未达到统计学显著性，表明有改善体温调节的趋势。
这些发现表明，补充甘油可增强与跑步经济性相关的关键代谢和生理因素，包括CCU、OCU、心血管反应以及训练有素的跑步者的主观用力程度。
