Kuikman Megan A, McKay Alannah K A, McCormick Rachel, Tee Nicolin, Vallance Brent, Ackerman Kathryn E, Harris Rachel, Elliott-Sale Kirsty J, Stellingwerff Trent, Burke Louise M
Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, Victoria, AUSTRALIA.
Athletics Australia, Melbourne, Victoria, AUSTRALIA.
Med Sci Sports Exerc. 2025 Jan 1;57(1):123-133. doi: 10.1249/MSS.0000000000003534. Epub 2024 Aug 23.
This study aimed to investigate the temporal effects of ~1800 m altitude exposure and energy availability (EA) manipulation on resting metabolic rate (RMR).
Twenty elite female race walkers underwent a 3-wk training camp at an altitude of 1800 m. During the first 2 wk, athletes consumed a high EA (HEA) diet of 45 kcal·kg fat-free mass (FFM) -1 ·d -1 . During the final week, half the athletes consumed a low EA (LEA) diet of 15 kcal·kg FFM -1 ·d -1 , whereas the others continued on an HEA diet. Athletes followed individualized training plans throughout the study. To assess the effect of altitude on RMR, athletes in the HEA group had RMR measured at baseline (580 m) before altitude exposure (Pre-alt), at 36 h (36h-alt), 2 wk (Wk2-alt), and 3 wk into altitude exposure (Wk3-alt), and at 36 h post-altitude exposure at ~580 m (36h-post). To assess the effect of LEA exposure on RMR while at altitude, athletes in the LEA group underwent RMR measurements at Pre-alt and before (Wk2-alt) and after the 7 d of LEA (Wk3-alt).
Compared with Pre-alt, the RMR of HEA athletes was increased at 36h-alt (+5.3% ± 3.1%; P = 0.026) and Wk2-alt (+4.9% ± 4.9%; P = 0.049), but was no longer elevated at Wk3-alt (+1.7% ± 4.2%; P = 0.850). The RMR of HEA athletes at 36h-post was lower than all timepoints at altitude ( P < 0.05) but was not different from Pre-alt (-3.9% ± 7.2%; P = 0.124). The 7-d period of LEA exposure at altitude did not affect RMR ( P = 0.347).
RMR was transiently increased with 1800-m altitude exposure in female athletes and was unaffected by short-term LEA. However, the altitude-induced increase was small (25-75 kcal·d -1 ) and was unlikely to have clinically significant implications for daily energy requirements.
本研究旨在调查海拔约1800米的暴露及能量可利用性（EA）调控对静息代谢率（RMR）的时间效应。
20名精英女子竞走运动员在海拔约1800米处进行了为期3周的训练营。在前2周，运动员摄入高能量可利用性（HEA）饮食，即45千卡·千克去脂体重（FFM）-1·天-1。在最后一周，一半运动员摄入低能量可利用性（LEA）饮食，即15千卡·千克FFM-1·天-1，而其他运动员继续摄入HEA饮食。在整个研究过程中，运动员遵循个性化训练计划。为评估海拔对RMR的影响，HEA组运动员在海拔暴露前（Pre-alt，约580米）、海拔暴露36小时（36h-alt）、2周（Wk2-alt）、3周（Wk3-alt）时以及海拔暴露后回到约580米处36小时（36h-post）测量RMR。为评估在海拔高度时LEA暴露对RMR的影响，LEA组运动员在Pre-alt以及LEA饮食7天前（Wk2-alt）和7天后（Wk3-alt）测量RMR。
与Pre-alt相比，HEA组运动员的RMR在36h-alt时升高（+5.3%±3.1%；P=0.026），在Wk2-alt时升高（+4.9%±4.9%；P=0.049），但在Wk3-alt时不再升高（+1.7%±4.2%；P=0.850）。HEA组运动员在36h-post时的RMR低于海拔高度时的所有时间点（P<0.05），但与Pre-alt无差异（-3.9%±7.2%；P=0.124）。在海拔高度进行7天的LEA暴露未影响RMR（P=0.347）。
在女子运动员中，海拔约1800米的暴露使RMR短暂升高，且不受短期LEA的影响。然而，海拔引起的升高幅度较小（约25 - 75千卡·天-1），对每日能量需求不太可能具有临床显著意义。
