Wang Anjie, Hurr Chansol
Department of Physical Education, Anhui Polytechnic University, Wuhu, China.
Integrative Exercise Physiology Laboratory, Department of Physical Education, Jeonbuk National University, Jeonju, South Korea.
J Sports Sci Med. 2024 Dec 1;23(4):799-811. doi: 10.52082/jssm.2024.799. eCollection 2024 Dec.
Ischemic preconditioning (IPC) is a strategy that may enhances endurance performance in thermoneutral environments. Exercising in the heat increases thermoregulatory and cardiovascular strain, decreasing endurance performance. The current study aimed to determine whether IPC administration improves endurance performance in the heat. In a randomized crossover design, 12 healthy subjects (V̇O: 54.4 ± 8.1 mL·kg·min) underwent either IPC administration (220 mmHg) or a sham treatment (20 mmHg), then completed a moderate-intensity 6-min running (EX1) and a high-intensity time-to-exhaustion running test (EX2) in a hot environment (35 °C, 50 % RH). Cardiac function, oxygen consumption (V̇O), and core body temperature (T) were measured. During EX2, IPC administration increased the total running time in the heat compared to the sham treatment (IPC: 416.4 ± 61.9 vs. sham 389.3 ± 40.7 s, = 0.027). IPC administration also increased stroke volume (IPC: 150.4 ± 17.5 vs. sham: 128.2 ± 11.6 ml, = 0.008) and cardiac output (IPC: 27.4 ± 1.7 vs. sham: 25.1 ± 2.2 ml min, = 0.007) during 100% isotime of EX2. End-exercise V̇O (IPC: 3.72 ± 0.85 vs. sham: 3.54 ± 0.87 L·min, = 0.017) and slow phase amplitude (IPC: 0.57 ± 0.17 vs. sham: 0.72 ± 0.22 L·min, = 0.016) were improved. When compared with the baseline period, an increase in T was less in the IPC condition during EX1 (IPC: 0.18 ± 0.06 vs. sham: 0.22 ± 0.08 °C, = 0.005) and EX2 (IPC: 0.87 ± 0.10 vs. sham: 1.03 ± 0.10 °C, < 0.001). IPC improves high-intensity endurance performance in the heat by 6.9 %. This performance benefit could be associated with improved cardiac and thermoregulatory function engendered by IPC administration.
缺血预处理（IPC）是一种可能提高在热中性环境下耐力表现的策略。在炎热环境中运动可增加体温调节和心血管负担，从而降低耐力表现。本研究旨在确定给予缺血预处理是否能改善在炎热环境中的耐力表现。在一项随机交叉设计中，12名健康受试者（V̇O：54.4±8.1 mL·kg·min）接受了缺血预处理（220 mmHg）或假处理（20 mmHg），然后在炎热环境（35°C，50%相对湿度）中完成了一次中等强度的6分钟跑步（EX1）和一次高强度的力竭时间跑步测试（EX2）。测量了心功能、耗氧量（V̇O）和核心体温（T）。在EX2期间，与假处理相比，给予缺血预处理增加了在炎热环境中的总跑步时间（缺血预处理：416.4±61.9秒 vs. 假处理：389.3±40.7秒，P = 0.027）。在EX2的100%等时期间，给予缺血预处理还增加了每搏输出量（缺血预处理：150.4±17.5 ml vs. 假处理：128.2±11.6 ml，P = 0.008）和心输出量（缺血预处理：27.4±1.7 ml/min vs. 假处理：25.1±2.2 ml/min，P = 0.007）。运动结束时的V̇O（缺血预处理：3.72±0.85 vs. 假处理：3.54±0.87 L·min，P = 0.017）和慢相幅度（缺血预处理：0.57±0.17 vs. 假处理：0.72±0.22 L·min，P = 0.016）得到改善。与基线期相比，在EX1期间缺血预处理组的T升高幅度较小（缺血预处理：0.18±0.06 vs. 假处理：0.22±0.08°C，P = 0.005），在EX2期间也是如此（缺血预处理：0.87±0.10 vs. 假处理：1.03±0.10°C，P < 0.001）。缺血预处理可使在炎热环境中的高强度耐力表现提高6.9%。这种表现上的益处可能与给予缺血预处理所带来的心功能和体温调节功能改善有关。
