Poor air quality

Smoke, pollution, or high pollen

If you head out

Check local air quality index (AQI) — many apps show it by hour.
AQI 0–100 is often fine for healthy adults; above 150, move indoors.
Run early when ozone and pollen counts are often lower.
A buff can help with pollen; it won't fix heavy smoke.

Indoor alternatives

Treadmill or gym cardio with filtered air.
Low-impact indoor options: elliptical, rowing machine, swimming.
Strength and mobility from your training plan's cross-training day.
Take a true rest day if air quality is hazardous — health beats the schedule.

Avoid outdoor exercise when air is rated unhealthy or hazardous, or when wildfire smoke is in your area.

LetsRunNow provides general fitness education, not medical advice. Talk to your doctor before starting or changing an exercise program — especially if you have a health condition, are pregnant, are recovering from injury or illness, or have not been active recently. Extreme heat, cold, or poor air quality carry real health risks — when in doubt, move your run indoors. Read our full terms.

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