A new study published in the journal Sports Medicine has shown that greater levels of air pollution on race days are associated with slower average marathon running times.
The study included estimated air pollution levels from nine major marathons in the United States from 2003 to 2019. Finishing times for each marathon were obtained from public data. Using spatial-temporal modeling, air pollution along each mile of each course was analyzed. The study focused specifically on fine particulate matter, which can come from sources like forest fires, vehicle emissions, and industrial activities. The goal of the study was to determine how levels of fine particulate matter pollution along marathon courses are related to average finishing times.
The results showed that greater pollution on race days was associated with slower average finishing times. Specifically, every 1 mcg/m3 increase in particulate matter was associated with a 32-second slower finishing time for men and a 25-second slower finishing time for women. These effects were more pronounced for faster runners, and they were present even for air pollution levels below current health-based standards.
The authors of the study noted that decreased marathon performance during higher pollution levels could have many potential causes, including increased blood pressure, constricted blood vessels, decreased lung function, respiratory discomfort, or other established negative health effects of air pollution. Previous studies have linked increases in air pollution, and particularly chronic air pollution, to heart disease, lung disease, and lung cancer. Marathon runners are typically healthy and fit individuals, and this study suggests that even they are susceptible to the negative effects of air pollution on health and performance. Further regulations on pollution from industrial and transportation-related sources are likely to both improve overall health and athletic performance for all people.
Sources: Sports Medicine, Science Daily
