A Warm Environment Reduces Exogenous Glucose Oxidation and Endurance Performance during Cycling with Facing Airflow.

IF 4.1 2区医学 Q1 SPORT SCIENCES

Medicine and Science in Sports and Exercise Pub Date : 2025-05-01 Epub Date: 2024-12-18 DOI:10.1249/MSS.0000000000003632

Kirsty M Reynolds, Mark P Funnell, Adam J Collins, Stephen A Mears, Jamie N Pugh, Lewis J James

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引用次数: 0

Abstract

Purpose: This study investigated the effect of cycling in a warm versus temperate environment with sufficient facing airflow on exogenous glucose use, performance, and GI responses.

Methods: Ten trained male cyclists/triathletes (36 ± 6 yr; 55 ± 6 mL·kg -1 ·min -1 ) completed V̇O 2peak and familiarization trials, and two experimental trials in 19°C (TEMP) and 32°C (WARM). Experimental trials involved 2-h cycling at ~50% W peak (preload) and an ~15-min time trial (TT) with fan-provided airflow covering the cyclist (preload ~29 km·h -1 , TT ~35 km·h -1 ). A glucose drink containing [U- 13 C]-glucose was consumed every 20 min during the preload (72 g·h -1 ).

Results: Average 40-120 min (TEMP 0.56 ± 0.13 g·min -1 ; WARM 0.48 ± 0.12 g·min -1 ; 15%; P = 0.015) and peak (TEMP 0.79 ± 0.18 g·min -1 ; WARM 0.68 ± 0.14 g·min -1 ; 14%; P = 0.008) exogenous glucose oxidation rates were reduced in WARM. TT performance was 15% slower in WARM (TEMP 819 ± 47 s; WARM 961 ± 130 s; P = 0.002). GI temperature ( P = 0.007), heart rate ( P < 0.001), and rating of perceived exertion ( P = 0.046) were greater during WARM. GI comfort ( P = 0.659) and intestinal fatty acid binding protein ( P = 0.094) were not different between trials.

Conclusions: These data demonstrate that the ability to use glucose provided in drinks was impaired during prolonged cycling in WARM. WARM ambient conditions impaired laboratory-based cycling performance, even with facing airflow approximating outdoor conditions, likely via impairments of thermoregulatory, cardiovascular, and metabolic function.

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面对气流骑车时，温暖的环境可降低外源性葡萄糖氧化和耐力表现。

在温暖的环境中锻炼会增加热/心血管压力，降低胃肠道（GI）的完整性和耐力表现。然而，基于实验室的研究几乎没有提供正面气流，这可能会加剧这些影响，特别是在循环过程中，对流冷却可能是热平衡的主要贡献者。目的：本研究探讨了在温暖和温和的环境中骑行对外源性葡萄糖的使用、性能和GI反应的影响。方法：10名训练有素的男性自行车/铁人三项运动员(36±6岁；（55±6 mL/kg/min）完成了V （o2）峰值和熟悉试验，并在19°C （TEMP）和32°C （WARM）下进行了两个实验试验。实验包括以50%峰值（预负荷）骑行2小时，以及在风扇提供气流覆盖骑行者的情况下骑行15分钟（预负荷：~29 km/h，预负荷：~35 km/h）。预负荷期间每20分钟饮用含[U-13C]-葡萄糖的葡萄糖饮料（72 g/h）。结果：平均40-120 min (TEMP 0.56±0.13 g/min；WARM 0.48±0.12 g/min；15%;P = 0.015)和峰值(TEMP 0.79±0.18 g/min；WARM 0.68±0.14 g/min；14%;P = 0.008)， WARM组外源性葡萄糖氧化降低。在WARM(温度819±47 s；961±130秒；P = 0.002)。GI温度（P = 0.007）、心率（P < 0.001）和RPE （P = 0.046）均高于WARM组。GI舒适度（P = 0.659）和肠脂肪酸结合蛋白（IFABP）（P = 0.094）在试验间无差异。结论：这些数据表明，在WARM的长时间循环中，利用饮料中提供的葡萄糖的能力受到损害。即使面对接近室外的气流，温暖的环境条件也会损害实验室的循环性能，这可能是通过损害体温调节、心血管和代谢功能来实现的。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Medicine and Science in Sports and Exercise 医学-运动科学

CiteScore

7.70

自引率

4.90%

发文量

2568

审稿时长

1 months

期刊介绍： Medicine & Science in Sports & Exercise® features original investigations, clinical studies, and comprehensive reviews on current topics in sports medicine and exercise science. With this leading multidisciplinary journal, exercise physiologists, physiatrists, physical therapists, team physicians, and athletic trainers get a vital exchange of information from basic and applied science, medicine, education, and allied health fields.