TL;DR — Because air pollution poses a number of harms to human health, it is important to work to mitigate air pollution levels at sporting events. Air pollution has demonstrated negative impacts on the physical and cognitive performance of athletes and sporting officials, and increased pollution levels that often surround sporting events also expose fans and spectators. Because of these harms, a number of sporting organizations such as the NCAA have outlined recommendations for limiting or stopping outdoor activity when air quality is poor to protect athlete health. By recognizing the impacts that air pollution has on athletes, as well as the ways that athletic events can increase pollution levels, we can work to mitigate these harms and support greater environmental consciousness in sports.

How air pollution affects athletic performance

Like with all individuals, exposure to air pollution has significant negative impacts on virtually all areas of the human body, both in the short-term and cumulatively.

To learn more about the multitude of ways that air pollution affects our health, read our blog here.

Athletes are often at an increased risk of severe impact from air pollution for a variety of reasons, including:

  • Because one’s ventilation rate increases during physical exercise, athletes inhale a greater proportion of pollutants during exercise than at rest
  • A larger proportion of air is inhaled through the mouth than the nose during physical activity, thus bypassing the nasal filtration system that helps to reduce pollutants entering the body
  • Pollutants can be inhaled more deeply into the body and can diffuse into the bloodstream faster during physical activity

Athletes that have pre-existing pulmonary or cardiac conditions face increased risk of these impacts.

A number of studies also show that air pollution negatively impacts athletic performance.

Several controlled studies have shown that exercise in combination with air pollutants like ozone and sulfur dioxide causes a significant increase in bronchoconstriction and airflow obstruction, as compared to the same pollution exposure during rest. 

In a study looking at collegiate track and field races, researchers found that even at air pollution levels below the EPA’s threshold for good air quality, training and competing at consistently higher levels of air pollution was associated with slower race times.

In strenuous athletic competition such as the Olympic Games where small increments of time often determine the ultimate success of athletes, the impact of air pollutants and subsequent adverse ventilatory changes can affect athletic performance”

— WE Pierson, 1989

Research on this phenomenon also shows that air pollution can impact cognition and error-making in athletes.

A 2023 study finds that higher air pollution levels predicted an increased number of errors and interceptions in professional baseball and football. The researchers also found that in counties with worse air quality, quarterback performance was significantly reduced.

Existing studies have examined the impacts of indoor air pollution on chess players’ performance.

After analysing 30,000 moves over the course of 596 games, the academic trio found that an surge in concentration of PM2.5 particles increased the players’ probability of making an erroneous move by 26.3%.”

— The Sustainability Report

Along with existing research on air pollution impacting mental and cognitive health, this research supports the findings that air pollution may also play a role in the decision-making capabilities of athletes.

The impact of air pollution extends beyond just the athletes. Research focused on Major League Baseball found that just a 1 parts per million (ppm) increase in carbon monoxide over a 3-hour period caused an 11.5% increase in umpires’ likelihood to make an incorrect call

Air quality guidelines for sports

Because of the abundance of research demonstrating the severe negative health impacts of air pollution exposure, many large sports organizations have initiatives in place to protect athletes, coaches, staff, and other involved individuals from air pollution exposure.

Air quality and outdoor activity guidance

Many sporting organizations make recommendations for appropriate activities based on air quality levels in accordance with the Air Quality Index (AQI).

The NCAA air quality recommendations state that:

  • At an AQI of 100 or higher, schools should consider having sensitive athletes — such as those with pre-existing pulmonary or cardiac conditions — removed from outdoor sporting activities, including practices and competitions, and monitored for respiratory impacts
  • At an AQI of 150 or higher, these sensitive athletes should be moved indoors, and all outdoor athletic activities should be shortened and reduced in intensity
  • At an AQI of 200 or higher, sporting authorities should seriously consider rescheduling the activity or moving it indoors, and avoiding prolonged exposure or heavy exertion
  • At an AQI of 300 or higher, activities must either be moved indoors or must be cancelled if doing so is not possible

The Pac-12 air quality guidelines note that many factors come into play when determining if an outdoor activity is safe, including:

  • The specific sport and its typical exertion levels
  • The AQI during the 3-24 hours preceding the event
  • The forecasted AQI
  • The weather forecast, including wind
The image above displays the Pac-12 air quality guidelines, showing the recommended alteration to sporting activities according to the corresponding AQI value. By taking appropriate action when the air quality reaches unhealthy levels, sporting authorities can protect athletes and staff and reduce harmful exposure. (Image source: Pac-12)

The devices that measure outdoor air quality

A variety of devices are useful in measuring outdoor air quality.

Reference-grade monitors, including federal reference method (FRM) and federal equivalent method (FEM) devices, represent the scientific standard for air quality monitoring. These air quality monitors have strict performance measurement standards and often serve as the basis for regulatory action.

Low-cost sensors are more flexibly sited and can collect air quality data at a greater spatial and temporal scale than reference-grade monitors, making them a crucial tool in collecting real-time, high-resolution data. 

To learn more about the different types of air quality monitoring technologies and the specific strengths of each, read our blog here.

As mentioned in the guidelines above, air quality levels and corresponding activity recommendations are often carried out using AQI values.

The AQI takes into account pollutant levels for ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen oxide when determining the air quality. When it comes to outdoor sporting activities, ground-level ozone and particulate matter tend to pose the most common and most concerning threat to human health.

Read our blog here to learn more about the AQI and other ways that air pollution levels are commonly communicated.

The impact of sporting events on air pollution

Sporting events can contribute significantly to pollution levels, particularly due to the volume of travel surrounding these events.

Studies looking at this phenomenon note that ground-level ozone and nitrogen dioxide — pollutants that can be linked to vehicle emissions — tend to be found in higher concentrations in the areas near stadiums during highly attended sporting events.

One potential solution is for governments and sports organizations to provide fans with low-emission alternatives to private vehicle use for traveling to events, such as public transit. Both teams and cities can work to encourage fans to choose these more environmentally friendly transport options.

In addition to threatening environmental health, these heightened air pollution levels can also expose spectators to the harmful impacts of poor air quality.

The impact of mega-events such as the Olympic Games on air quality

The Olympic Games can threaten heightened air pollution levels — not only due to transportation surrounding the event but also due to the construction of stadiums and large sporting facilities and the consumption of energy and resources to put on the event.

Accordingly, the International Olympic Committee (IOC) outlines a global air quality plan on their Manual on Sport and the Environment, which involves:

  • Monitoring air pollution emissions
  • Encouraging major polluters to take steps to permanently reduce their emissions prior to the event
  • Establishing energy management strategies
  • Encouraging transportation fleet operators to reduce their emissions
  • Working with municipal offices to reduce traffic

However, mega-events such as the Olympics can also act as a catalyst for air quality improvement.

The 2008 Olympics prompted a handful of Chinese cities to cut pollution and sustain a blue sky: Cities with air quality regulated for the Olympics cut their Air Pollution Index by about 16 points during the Games, compared to non-regulated cities, and 60% of that effect remained four years after the event”

— Fang et al., 2022

Another study looking at Beijing, this time during the 2022 Winter Olympics, found a 25% reduction in the AQI values and a 28% decrease in PM2.5 levels. Trend analysis suggests that these Olympics were part of a long-term trend of air quality improvement in the region.

Sporting organizations have a responsibility to promote cleaner air for fans and athletes

Sports leagues can also encourage action on air pollution through initiatives such as the UEFA’s “Cleaner Air, Better Game” campaign, which aims to raise awareness about the harms of air quality and promote collective action to reduce carbon emissions during the European Under-21 Championship.

The campaign encourages all stakeholders — including players, fans, volunteers, staff, and national associations — to adopt environmentally conscious practices in combination with a number of actions taken by UEFA and host country organizations to promote air quality and climate health.

Interested in measuring air quality for cleaner air and a healthier climate? Get in touch with our team to learn more about our Sensing-as-a-Service solution for governments, businesses, and community organizations, using our Clarity Node-S monitors and Modules.