About the Air Quality & Exercise Planner
Air quality sites tell you a number; this planner tells you what to do with your run. It pulls the live US AQI and pollutant levels for your location and applies EPA activity guidance scaled by the thing generic dashboards ignore: how hard you will be breathing. An easy walk at AQI 130 and hour of intervals at AQI 130 are completely different exposures — ventilation rises more than ten-fold with intensity, and mouth breathing bypasses the nose's filtering.
Built for the wildfire-smoke era: runners and cyclists deciding whether to train through a hazy week, parents timing park trips, and anyone in a sensitive group who needs earlier warnings than the general-public cutoffs. The hourly chart usually finds a workable window even on marginal days — shifting a run beats skipping it.
Your location is detected from your connection solely to fetch nearby air data and is never stored. Verdicts follow published EPA and WHO guidance but are planning aids, not medical advice — anyone with heart or lung conditions should confirm personal thresholds with their doctor.
PM2.5 = smoke/haze (worst mornings under inversions). Ozone = smog (worst hot, sunny afternoons).
How to Use the Air Quality Exercise Planner
Confirm your location, pick the intensity you actually plan to train at, and read the verdict. The AQI hero uses the standard EPA color bands, but the banner below it is the real output: a go / shorten / move-indoors call calibrated to how hard you will be breathing. If the answer is “not now,” check the hourly chart before giving up — AQI routinely swings 30 to 50 points within a single day, and the highlighted cleanest hour is often all you need.
The Ventilation Problem: Why Runners Need Stricter Cutoffs
At rest you move about 6 liters of air per minute through your lungs. On an easy jog that becomes 40–60; during hard intervals, elite athletes exceed 150. Exercise also switches you to mouth breathing, bypassing the nasal passages that filter larger particles, and deeper breaths carry pollutants further into the alveoli. The practical consequence: a one-hour tempo run at AQI 120 can deliver a particulate dose comparable to spending the whole day outside at rest. Air-quality apps built for the general public miss this entirely — their “OK for everyone” band can be a poor choice for a hard session, which is exactly the gap the intensity selector closes.
Reading the AQI Bands Like an Athlete
- 0–50 (Good): Train normally at any intensity.
- 51–100 (Moderate): Fine for healthy adults; unusually sensitive people should watch for symptoms during long, hard efforts.
- 101–150 (Unhealthy for Sensitive Groups): Healthy adults: shorten or ease hard sessions. Sensitive groups: keep it easy and brief, or go indoors.
- 151–200 (Unhealthy): Everyone should cut intensity and duration; sensitive groups move indoors. This is where smoke days usually land.
- 201+ (Very Unhealthy / Hazardous): Indoor training only — and check your indoor filtration.
Smoke vs Smog: Two Different Enemies, Two Different Schedules
PM2.5 — wildfire smoke, wood stoves, exhaust haze — is a particle problem. It is typically worst in the early morning, when overnight temperature inversions trap emissions near the ground, and improves as afternoon mixing stirs the atmosphere. Ozone is a gas cooked from precursor emissions by sunlight, so it does the opposite: near-zero at dawn, peaking between 2 and 6 PM on hot, sunny days. The classic athlete’s mistake is training at 5 PM in July (peak ozone) or 6 AM during a smoke event (peak PM2.5) — precisely backwards for the pollutant in play. The Pro outlook table splits the two so you can pick the right end of the day.
Training Through a Smoke Week Without Losing Fitness
A multi-day smoke event does not have to erase a training block. Move quality sessions to the cleanest windows the ranking finds; convert outdoor hard days into indoor trainer or treadmill sessions; and downgrade outdoor efforts to easy aerobic work, which cuts ventilation — and dose — by more than half compared to intervals of the same duration. Symptoms that warrant stopping: chest tightness, wheezing, unusual cough, or a scratchy throat that worsens mid-session. Performance itself degrades measurably above AQI 100, so the “push through it” option costs you twice.
Pair this with the Calories Burned Calculator for the session itself, or the UV & Vitamin D Planner for the other outdoor exposure that matters. Browse all Health & Fitness tools for more.
Frequently Asked Questions
What AQI is safe for running?
For healthy adults, vigorous outdoor exercise is generally fine below AQI 100, worth shortening between 101 and 150, and better moved indoors above 150. Sensitive groups — people with asthma or heart disease, children, older adults, and pregnant people — should shift those cutoffs down by roughly one category. These bands follow US EPA activity guidance; consult a doctor about your personal thresholds.
Why does exercise intensity change the safe AQI level?
Ventilation. At rest you breathe about 6 liters of air per minute; an easy jog raises that to 40 or more and hard intervals can exceed 100. You also switch to mouth breathing, bypassing the nose's filtration. A hard hour at AQI 120 can deliver as much PM2.5 to your lungs as a full day of sitting outside, which is why the verdict here tightens as intensity rises.
What is PM2.5 and why is it the number everyone watches?
Particulate matter smaller than 2.5 micrometers — wildfire smoke, exhaust, and industrial haze — is small enough to reach the deepest parts of the lungs and pass into the bloodstream. The WHO 24-hour guideline is 15 micrograms per cubic meter. During wildfire events readings can exceed 150, at which point outdoor exertion is inadvisable for everyone.
Why is ozone worst in the afternoon while smoke is often worst in the morning?
Ground-level ozone is created by sunlight cooking traffic emissions, so it peaks mid-afternoon on hot sunny days and falls overnight — early morning is the classic low-ozone window. Smoke and PM2.5 do the opposite: overnight temperature inversions trap particles near the ground, so mornings are often dirtiest until the atmosphere mixes. That is exactly why the tool shows both pollutants separately.
Do masks or indoor workouts actually help on bad-air days?
A well-fitted N95 filters most PM2.5 but does nothing for ozone, and hard breathing through one is difficult, so masks suit commutes better than workouts. Indoor air with decent filtration typically carries 50 to 80 percent less PM2.5 than outdoors during smoke events, making an indoor session the reliable fallback the tool recommends at high AQI.
