Respiratory physicians should tailor exercise advice during periods of high air pollution, with recommendations adjusted to each patient’s risk factors, according to new expert guidance.
In a paper in Chest [link here], clinicians offered practical advice for patients who ask whether it is safe to exercise during increasingly common episodes of dangerous pollution. They proposed a framework to risk stratify patients, interpret air quality data, apply action thresholds and modify the timing, location, intensity and duration of exercise.
The authors, led by Dr Matthew Glick of the University of Utah, wrote that the framework emphasised dose reduction and modification rather than blanket cessation. They said it acknowledged differences in individual susceptibility and access to mitigation resources and supported shared decision making at the point of care. They added that integrating air quality awareness into routine exercise counselling could help clinicians deliver clear and clinically actionable guidance that keeps patients active while reducing avoidable exposure.
The paper noted that unhealthy air episodes were becoming more frequent due to wildfire smoke, traffic emissions and weather patterns that trap pollutants. This created a paradox for respiratory health because exercise is beneficial, yet increased ventilation can heighten the harmful effects of pollution.
The authors wrote that the question was not whether patients should exercise, but at what combination of pollutant concentration and sustained ventilation the dose eroded net benefit, particularly for patients with limited cardiopulmonary reserve. They said evidence suggested exercise benefits outweighed harms except when air quality was extremely poor for long periods.
They recommended three principles. Most patients should maintain regular exercise because inactivity is more harmful long term. Susceptibility varies, with COPD, asthma, interstitial lung disease, pulmonary hypertension and cardiovascular disease patients at higher risk of symptoms from pollution. Exercise dose can be modified to reduce inhaled pollution.
They proposed a four stage framework. First, patients are risk stratified based on disease, vulnerability factors and baseline exercise capacity to identify those at higher risk of symptoms, exacerbations or cardiovascular events from small increases in exposure.
Second, patients should be counselled on how to interpret air quality. The authors based their advice on the US AQI categories of Good, Moderate, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy and Hazardous. The UK Daily Air Quality Index has similar levels of low, moderate, high and very high pollution.
Third, clinicians should combine the patient’s risk level with current air quality to decide whether to modify the timing, intensity, route or duration of outdoor exercise, move indoors or avoid outdoor exercise.
Lastly, they recommended exercise with appropriate modifications to timing, location, type, intensity and duration. They noted that patients with chronic lung conditions such as asthma, COPD or fibrotic ILD were most susceptible to acute effects and reduced benefit. Older adults also required particular consideration.
The authors concluded that earlier transitions to indoor activity and targeted mitigation such as clean indoor air and selective respirator use were appropriate for higher risk patients. They added that future work should define long term joint effects and identify scalable strategies that expand equitable access to cleaner air.