Department of Sport, Health and Nutrition, Leeds Trinity University, Horsforth, Leeds,United Kingdom.
School of Sport, Health and Exercise Sciences, University of Portsmouth, Portsmouth,United Kingdom.
Int J Sports Physiol Perform. 2022 May 17;17(7):1119-1125. doi: 10.1123/ijspp.2022-0020. Print 2022 Jul 1.
The Doha 2019 women's World Championship marathon took place in extreme hot (32 °C), humid conditions (74% relative humidity) culminating in unprecedented (41%) failure rates. We explored whether extreme heat or suboptimal pacing was responsible for diminished performance against a temperate "control" (London 2017: 19 °C, 59% relative humidity) and whether physical characteristics (eg, body surface area, estimated maximal oxygen uptake, habitual heat exposure) explained performance.
Five-kilometer-pace (km·h-1) data underwent repeated-measures analyses of hot (Doha, n = 40) versus temperate pacing and performance (London, n = 78) within and between marathon pacing (finisher quartiles normalized against personal best; n = 10 per group) and within hot marathon finishers versus nonfinishers (up to 10 km; normalized data). Possible predictors (multiple regression) of hot marathon pacing were explored. Tests to .05 alpha level, partial eta squared (ηp2) indicates effect size.
Mean (SD) of Doha (14.82 [0.96] km·h-1) pace was slower (London: 15.74 [0.96] km·h-1; P = .00; ηp2=.500). In hot conditions, athletes finishing in positions 1 to 10 (group 1) started more conservatively (93.7% [2.1%] of personal best) than slower runners (groups 3 and 4; 96.6% [2.8%] of personal best; P < .05, ηp2=.303). Groups were not different at 15 km and then slowed immediately (groups 3 and 4) or after 20 km (group 2). Finishers and nonfinishers adopted similar pace up to 10 km (P > .05, ηp2 =.003). World ranking predicted (P = .00; r2 = .248) average pace in Doha.
Extreme hot conditions reduced performance. Top 10 athletes adopted a conservative initial pace, whereas lower-placing athletes adopted a faster, aggressive start. Pacing alone does not explain high failure rates in nonfinishers. Athletes competing in the heat should initially pace conservatively to optimize performance.
2019 年多哈女子世界锦标赛马拉松比赛在极端炎热（32°C）和高湿度（74%相对湿度）的条件下进行，导致创纪录的（41%）失败率。我们探讨了极端高温或次优配速是否是导致表现下降的原因，与较温和的“对照”（2017 年伦敦：19°C，59%相对湿度）相比，以及身体特征（例如体表面积、估计最大摄氧量、习惯性热暴露）是否可以解释表现。
对 5 公里配速（km·h-1）数据进行了重复测量分析，比较了高温（多哈，n=40）与温和条件（伦敦，n=78）下的配速和表现，并比较了马拉松比赛中的个人最佳成绩（按个人最佳成绩进行归一化；每组 10 人）和高温马拉松完赛者与未完赛者（最多 10 公里；归一化数据）之间的配速。还探讨了高温马拉松配速的可能预测因素（多元回归）。.05 水平的检验，部分 eta 平方（ηp2）表示效应大小。
多哈的平均（SD）配速（14.82[0.96] km·h-1）较慢（伦敦：15.74[0.96] km·h-1；P=.00；ηp2=.500）。在高温条件下，排名前 1 到 10 的运动员（第 1 组）的起跑速度更为保守（个人最佳成绩的 93.7%[2.1%]），而速度较慢的运动员（第 3 组和第 4 组）的起跑速度更快（个人最佳成绩的 96.6%[2.8%]；P<.05，ηp2=.303）。第 15 公里时，各组没有差异，然后立即减速（第 3 组和第 4 组）或在第 20 公里时减速（第 2 组）。完赛者和未完赛者在 10 公里之前采用了相似的配速（P>.05，ηp2=.003）。世界排名预测（P=.00；r2 =.248）多哈的平均配速。
极端高温条件降低了表现。前 10 名运动员采用了保守的初始配速，而排名较低的运动员采用了更快、更激进的起跑方式。配速本身并不能解释未完成比赛的高失败率。在炎热天气中比赛的运动员应在开始时保持保守配速，以优化表现。
