Running for Clean Air - dynamic monitoring in Warsaw (© World Athletics)
• Initiative identifies the healthiest day to run in the city
Running for Clean Air has reached a major milestone with the publication of its inaugural report, demonstrating the impact of the initiative for cities looking to combat air pollution.
Running for Clean Air is a World Athletics project, funded by the Clean Air Fund. Its objective is to address air pollution in urban areas, using city marathons as a powerful platform. By integrating air quality monitoring and public awareness campaigns into road running events, the initiative seeks to make clean air a priority for city governments, event organisers and the public, ultimately contributing to healthier urban environments and better conditions for physical activity.
The initiative kicked off in Warsaw in Poland in March and has already launched in a second city, with August marking the start of Running for Clean Air in Lagos, Nigeria. The inaugural campaign concluded at the Warsaw City Marathon in September, leading to the publication of the project’s first report.
Minimising personal exposure
Running for Clean Air has been monitoring air quality and heat stress in one of Warsaw’s city parks for five months. By analysing the data collected, it is possible to identify the optimal days and times for exercise at that location.
Air pollution is ever-present and its threats to human health are undeniable. While the health benefits of regular exercise generally outweigh the risks associated with air pollution, it’s important to stay informed about local air quality conditions. Adjusting the timing and intensity of workouts to match cleaner air periods can make a significant difference.
Running for Clean Air Warsaw 2024 employed the project’s previously developed and scientifically documented methodology. A high-quality sensor was installed in a Warsaw city park to collect data over five months – this extended monitoring period allowed patterns to be observed and identification of the safest times for exercise at the location.
Key findings: the cleanest and dirtiest days
Looking at the graphs below, Friday clearly stands out as the most polluted day of the week in Warsaw, while Sunday and Monday lie on the opposite end of the spectrum. The high values on Fridays are mainly caused by individually high values of ozone and particulate matter, the most prominent pollutants recorded at this location.
Daily evolution of AQI EU throughout the project period
AQI EU stands for the European Air Quality Index and serves as an air quality indicator, aggregating the individual values of five pollutants: O3, NO2, NO, PM2.5, and PM10. The value of the index corresponds to the poorest value of any of the five pollutants.
Timing matters: the cleanest hours
Hourly evolution of AQI EU throughout the project period
When examining pollution levels throughout the day, the data shows that air quality peaks between 12:00pm and 2:00pm, driven by ozone levels. This mid-afternoon rise occurs as the fumes from the morning commute react with sunlight. After this peak, pollution levels gradually decline.
This provides a good indication as to the most suitable times for physical activity at this location. For anyone regularly exercising in this area, the report provides a recommendation of adjusting exercising times to avoid the air pollution peaks. If rescheduling workouts isn’t feasible, athletes can consider reducing their intensity or duration during these periods.
See full results and recommendations in the summary report.
A local perspective with broader implications
While this data is hyperlocal and reflects the situation in the park where the sensor was installed, some conclusions may apply to other locations and having access to local air quality data is critical for making informed decisions.
It is hoped that by sharing this in-depth data for Warsaw, other cities will be inspired to follow suit.
It is always better to exercise, even in poor air
World Athletics champions physical activity as a cornerstone of a healthy lifestyle. While air pollution is a valid concern, it is proven that the health benefits of exercise in most regions outweigh the risks posed by polluted air. For the general population, it is far better to stay active, even in less-than-ideal air quality.
Professional athletes, however, may require more tailored guidance.
Building on years of research
World Athletics has prioritised air quality since 2017, producing multiple scientific publications under the guidance of its Health & Science Department. This research serves as the backbone of the organisation’s commitment to addressing global air quality, which is now one of the six pillars of its sustainability strategy.
Thanks to the partnership with the Clean Air Fund, this work has expanded to include practical, real-world applications of scientific findings.
As the example of the Warsaw running community demonstrates, sport has the power to unite people around important social and environmental issues. It shows, too, that communities genuinely care about the quality of the air they breathe, and with support and the right data, they can make a positive difference.
Visit the project website to learn more.