Living in this area, we already have a strong tendency to overdo exercise. As health care practitioners, we see overuse injuries all the time. And you know you don’t always give your body time to rest and recover after a big event or to heal after an injury. How likely are we to temper our exercise enthusiasm during wildfire smoke, and how necessary is it really?

Is exercising outdoors when it is smoky doing us more harm than good?

Good question. And a bit of a complicated one.

What is in wildfire smoke that is dangerous?

First, lets talk about the type of particles released from wildfires. Most specifically the particle called PM2.5 — fine particulate matter smaller than 2.5 micrometers in diameter.
The scary thing about PM2.5 particles is that they are easily breathed in, and once they hit our lungs they cause irritation and inflammation with sometimes serious repercussions.

Image Credit: Jen Burgess/IsolineStudios for BC Centre for Disease Control.

For most of us, we have mild symptoms such as:
• Itchy or watery eyes
• Sore throat
• Runny nose
• Mild cough
• Phlegm & mucus production
• Wheezing
• Headache

More serious symptoms can result such as:
• Shortness of breath
• Severe cough
• Dizziness
• Chest pain
• Heart palpitations

If you are experiencing these, get out of the smoke and please get medical attention if symptoms persists.

Children, the elderly and those with lung conditions are more affected by air quality and should be more careful to avoid exposure.

Children’s airways are still developing and they breathe more air per pound of body weight than adults. Source

How to Check Air Quality

Look at both the Air Quality Index (AQI) and specifically the PM2.5 measurement for your area. I use AirNow

Well, the Air Quality Index is not looking great, but I want to exercise. Consider these options:

Exercise indoors in a place with a good air filtration system, specifically with a HEPA filter.

Monitor the Air Quality and choose your time of day for exercise based on that.

Anecdotally, I notice less smoke here in the morning and like to get out then.

Do lower intensity exercise.

While doing strenuous exercise you breathe 10 times more air than while resting, thus increasing your exposure to these particles by 10 times. Less gasping for air equals less exposure. Source

Change your elevation.

Sometimes you can get above the smoke. Try a hike at the top of Teton Pass, off the Tram or your own high elevation favorite.  Keep in mind, it’s not always comforting to look down at the smoke below you.

Drink water and eat a diet that will help you combat the inflammation caused by the smoke.

Consider a respirator/ N95 mask.

If you work outside or for low intensity exercise, wear a respirator/ N95 mask. A well-fitted N95 can reduce PM2.5 exposure by 95% Personally, I can’t handle wearing one while running or biking, but despite the annoyance I can walk with one on. You can find them at the hardware store.

Dr Laura with N95 Respirator on a smoky day
Dr Laura sporting the N95 respirator on a smoky day

More harm than good exercising outside in wildfire smoke? Not necessarily.

Although this study was done in an urban area, measuring urban pollutants, the PM2.5 levels were considered, low intensity exercise, eg. commuting by bike or walking, seems to convey health benefits that outweigh the harm for healthy adults when the PM2.5 levels are under 95 μg/m3 and for lower concentrations, less than or equal to 22 μg/m3 the outlook is better.

“PM2.5 concentration (22 μg/m3) benefits of physical activity by far outweigh risks from air pollution even under the most extreme levels of active travel. In areas with PM2.5 concentrations of 100 μg/m3, harms would exceed benefits after 1 h 30 min of cycling per day or more than 10 h of walking per day.  For half an hour of cycling every day, the background PM2.5 concentration would need to be 95 μg/m3 to reach the tipping point.” Read the study

Bear in mind this study was done in urban areas with more pollution than wildfire smoke causing the increased PM2.5 and that they were commuting by bike, not charging up Ferrin’s or Putt-Putt.

The truth is we need more data to determine the risks vs benefits.

Want to be a citizen scientist and help contribute data to support research on the health impacts of wildfire smoke? Download the EPA’s Smoke Sense app. You can view air quality, see where fires are burning and report your smoke observations and health symptoms.

Thank you for reading. Play it safe out there!