Effect of Heat Acclimatization, Heat Acclimation, and Intermittent Heat Training on Maximal Oxygen Uptake.

IF 2.7 2区医学 Q1 SPORT SCIENCES

Sports Health-A Multidisciplinary Approach Pub Date : 2025-03-01 Epub Date: 2024-05-06 DOI:10.1177/19417381241249470

Ryan A Dunn, Lauren A Fry, Yasuki Sekiguchi, Courteney L Benjamin, Ciara N Manning, Robert A Huggins, Rebecca L Stearns, Douglas J Casa

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引用次数: 0

Abstract

Background: Maximal oxygen uptake (VO_2max) is an important determinant of endurance performance. Heat acclimation/acclimatization (HA/HAz) elicits improvements in endurance performance. Upon heat exposure reduction, intermittent heat training (IHT) may alleviate HA/HAz adaptation decay; however, corresponding VO_2max responses are unknown.

Hypothesis: VO_2max is maintained after HAz/HA; IHT mitigates decrements in aerobic power after HAz/HA.

Study design: Interventional study.

Level of evidence: Level 3.

Methods: A total of 27 male endurance runners (mean ± SD; age, 36 ± 12 years; body mass, 73.03 ± 8.97 kg; height, 178.81 ± 6.39 cm) completed VO_2max testing at 5 timepoints; baseline, post-HAz, post-HA, and weeks 4 and 8 of IHT (IHT₄, IHT₈). After baseline testing, participants completed HAz, preceded by 5 days of HA involving exercise to induce hyperthermia for 60 minutes in the heat (ambient temperature, 39.13 ± 1.37°C; relative humidity, 51.08 ± 8.42%). Participants were assigned randomly to 1 of 3 IHT groups: once-weekly, twice-weekly, or no IHT. Differences in VO_2max, velocity at VO_2max (vVO₂), and maximal heart rate (HR_max) at all 5 timepoints were analyzed using repeated-measure analyses of variance with Bonferroni corrections post hoc.

Results: No significant VO_2max or vVO₂ differences were observed between baseline, post-HAz, or post-HA (P = 0.36 and P = 0.09, respectively). No significant group or time effects were identified for VO_2max or vVO₂ at post-HA, IHT₄, and IHT₈ (P = 0.67 and P = 0.21, respectively). Significant HR_max differences were observed between baseline and post-HA tests (P < 0.01). No significant group or time HR_max differences shown for post-HA, IHT₄, and IHT₈ (P = 0.59).

Conclusion: VO_2max was not reduced among endurance runners after HA/HAz and IHT potentially due to participants' similar aerobic training status and high aerobic fitness levels.

Clinical relevance: HAz/HA and IHT maintain aerobic power in endurance runners, with HAz/HA procuring reductions in HR_max.

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热适应、热适应和间歇热训练对最大摄氧量的影响。

背景：最大摄氧量（VO2max最大摄氧量（VO2max）是决定耐力表现的重要因素。热适应/热适应（HA/HAz）可提高耐力表现。在减少热暴露后，间歇性热训练（IHT）可能会缓解热适应/热适应衰减；然而，相应的最大氧饱和度（VO2max）反应尚不清楚：假设：HAz/HA后，最大氧饱和度（VO2max）保持不变；IHT可减轻HAz/HA后有氧功率的下降：研究设计：干预性研究：证据等级：3级：共有 27 名男性耐力跑运动员（平均值 ± SD；年龄，36 ± 12 岁；体重，73.03 ± 8.97 千克；身高，178.81 ± 6.39 厘米）在 5 个时间点完成了 VO2max 测试：基线、HAz 后、HA 后、IHT 第 4 周和第 8 周（IHT4、IHT8）。基线测试后，参与者完成 HAz，在此之前进行为期 5 天的 HA，包括在高温（环境温度为 39.13 ± 1.37°C；相对湿度为 51.08 ± 8.42%）条件下进行 60 分钟的热身运动。参与者被随机分配到 3 组中的 1 组：每周 1 次、每周 2 次或不进行 IHT。采用重复测量的方差分析方法分析了所有 5 个时间点的最大氧饱和度（VO2max）、最大氧饱和度时的速度（vVO2）和最大心率（HRmax）的差异，并进行了 Bonferroni 校正：基线、HAz 后或 HA 后的 VO2max 或 vVO2 无明显差异（分别为 P = 0.36 和 P = 0.09）。在 HA 后、IHT4 和 IHT8，VO2max 或 vVO2 没有发现明显的组或时间效应（分别为 P = 0.67 和 P = 0.21）。在基线测试和 HA 后测试之间观察到了显著的心率最大值差异（P < 0.01）。HA后、IHT4和IHT8没有显示出明显的组别或时间心率最大值差异（P = 0.59）：结论：HA/HAz 和 IHT 后，耐力跑运动员的 VO2max 没有降低，这可能是因为参与者的有氧训练状况相似且有氧体能水平较高：临床相关性：HAz/HA 和 IHT 可保持耐力跑运动员的有氧能力，HAz/HA 可降低最大心率。

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

Sports Health-A Multidisciplinary Approach Medicine-Orthopedics and Sports Medicine

CiteScore

6.90

自引率

9.10%

发文量

101

期刊介绍： Sports Health: A Multidisciplinary Approach is an indispensable resource for all medical professionals involved in the training and care of the competitive or recreational athlete, including primary care physicians, orthopaedic surgeons, physical therapists, athletic trainers and other medical and health care professionals. Published bimonthly, Sports Health is a collaborative publication from the American Orthopaedic Society for Sports Medicine (AOSSM), the American Medical Society for Sports Medicine (AMSSM), the National Athletic Trainers’ Association (NATA), and the Sports Physical Therapy Section (SPTS). The journal publishes review articles, original research articles, case studies, images, short updates, legal briefs, editorials, and letters to the editor. Topics include: -Sports Injury and Treatment -Care of the Athlete -Athlete Rehabilitation -Medical Issues in the Athlete -Surgical Techniques in Sports Medicine -Case Studies in Sports Medicine -Images in Sports Medicine -Legal Issues -Pediatric Athletes -General Sports Trauma -Sports Psychology