マラソンパフォーマンスにおける空気質の影響を分析した16年の研究 (For optimal marathon performance, check training plan, gear, nutrition, weather ― and air quality?)

2024-12-18 ブラウン大学

<関連情報>

• https://www.brown.edu/news/2024-12-18/marathon-air-pollution
• https://link.springer.com/article/10.1007/s40279-024-02160-8

排気ガスで走る:2003年から2019年までの米国主要マラソン9大会における微粒子物質の完走時間への影響の分析 Running on Fumes: An Analysis of Fine Particulate Matter’s Impact on Finish Times in Nine Major US Marathons, 2003–2019

Elvira S. Fleury,Gray S. Bittker,Allan C. Just & Joseph M. Braun
Sports Medicine  Published:18 December 2024
DOI:https://doi.org/10.1007/s40279-024-02160-8

Abstract

Background
Under controlled conditions and in some observational studies of runners, airborne fine particulate matter smaller than 2.5 microns in diameter (PM_2.5) is associated with exercise performance decrements.

Objective
To assess the association between event-day fine particulate matter air pollution (PM_2.5) and marathon finish times.

Methods
Using a spatiotemporal machine-learning model, we estimated event-day racecourse-averaged PM_2.5 concentrations for nine major US marathons (2003–2019). We obtained 1,506,137 male and 1,058,674 female finish times from 140 event-years of public marathon data. We used linear and quantile mixed models to estimate the mean and percentile-specific year and heat index-adjusted effect of 1 µg/m³ higher event-day racecourse-averaged PM_2.5 on marathon finish times in sex-stratified samples.

Results
Analyzing all finish times, 1 µg/m³ higher race-day PM_2.5 was associated with 32-s slower average finish times among men (95% confidence limits (CL) 30, 33 s) and 25-s slower average finish times among women (95% CL 23, 27 s). Quantile-specific associations of event-day PM_2.5 with finish times were larger for faster-than-median finishers. While PM_2.5 was generally associated with slower finish times in single-event models, there was effect heterogeneity, and most 95% confidence intervals included the null.

Conclusion
Greater race-day PM_2.5 was associated with slower average marathon finish times, with more pronounced effects in faster-than-median runners. While more research is needed to characterize effect heterogeneity across the performance spectrum, these findings show the impact of PM_2.5 on marathon performance and the importance of considering data from multiple competitions when estimating PM_2.5 effects from event-level data.