July 6th, 2024 | by Peggy Shinn
An interview with respiratory therapist David Michaels
Last summer, huge swaths of the United States were covered by smoke billowing down from Canadian wildfires. Images of New York City in an orange haze were apocalyptic, and air quality alerts were rampant, urging the young, old, and those with respiratory problems to stay inside.
But did those air quality alerts apply to us — healthy cyclists with big lung capacities? We are like letter carriers, with neither rain, sleet, hail nor snow keeping us from training. But should we heed air quality alerts?
I asked a long-time cycling friend who’s a respiratory therapist to weigh in on how wildfire smoke and poor air quality in general can affect even the healthiest among us. David Michaels lives in Eden, Utah (as much of a mountain paradise as it sounds), and has been a respiratory therapist for over 20 years and an avid cyclist for twice that long.
But before I dive into a Q&A with David, let’s talk about the Air Quality Index (AQI). It measures five pollutants: ground-level ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulates. With wildfire smoke, we’re mostly concerned about gasses from burning buildings and manmade debris and particulate matter: soot, ash, and dust.
The AQI scale goes from 0 to 500. EPA runs a website called AirNow. Enter your zip code, and it will show you the air quality on a color scale (from green to maroon).
If the index is under 100, you’re good to go. The AQI is in the green and yellow.
But over 100, the scale tips into the orange, indicating that the air is bad for children, pregnant women, older people, and those with diabetes, kidney disease, and people with respiratory problems, such as asthma, chronic bronchitis, COPD, and cardiovascular concerns. It’s also not great for athletes who are outdoors and breathing hard.
(While the U.S. Centers for Disease Control and Prevention (CDC) says N95 masks, when worn properly, can offer some protection against particulate inhalation from smoke, as we all remember from the Covid-19 mask mandates, it’s not easy breathing hard through an N95 mask.)
An interview with respiratory therapist David Michaels
Last summer, huge swaths of the United States were covered by smoke billowing down from Canadian wildfires. Images of New York City in an orange haze were apocalyptic, and air quality alerts were rampant, urging the young, old, and those with respiratory problems to stay inside.
But did those air quality alerts apply to us — healthy cyclists with big lung capacities? We are like letter carriers, with neither rain, sleet, hail nor snow keeping us from training. But should we heed air quality alerts?
I asked a long-time cycling friend who’s a respiratory therapist to weigh in on how wildfire smoke and poor air quality in general can affect even the healthiest among us. David Michaels lives in Eden, Utah (as much of a mountain paradise as it sounds), and has been a respiratory therapist for over 20 years and an avid cyclist for twice that long.
But before I dive into a Q&A with David, let’s talk about the Air Quality Index (AQI). It measures five pollutants: ground-level ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulates. With wildfire smoke, we’re mostly concerned about gasses from burning buildings and manmade debris and particulate matter: soot, ash, and dust.
The AQI scale goes from 0 to 500. EPA runs a website called AirNow. Enter your zip code, and it will show you the air quality on a color scale (from green to maroon).
If the index is under 100, you’re good to go. The AQI is in the green and yellow.
But over 100, the scale tips into the orange, indicating that the air is bad for children, pregnant women, older people, and those with diabetes, kidney disease, and people with respiratory problems, such as asthma, chronic bronchitis, COPD, and cardiovascular concerns. It’s also not great for athletes who are outdoors and breathing hard.
(While the U.S. Centers for Disease Control and Prevention (CDC) says N95 masks, when worn properly, can offer some protection against particulate inhalation from smoke, as we all remember from the Covid-19 mask mandates, it’s not easy breathing hard through an N95 mask.)
Peggy: What kind of damage does smoke do to our lungs?
David:First, people with underlying health conditions have a higher risk of lung damage from smoke inhalation. [But for all of us], when you have particulate matter going into the lungs, anything smaller than 2.5 microns can lodge in the lung tissue. It can cause difficulty breathing, coughing, runny nose, irritated eyes.
Particles lodged in the lungs are attacked by phagocytes, which try to engulf and digest the foreign particles.
If they can't kill the particulates, the body takes these cells and puts a hard coating around them, so the lungs actually get hard and are scarred. Anywhere the lungs are hard, they are stiffer and won't absorb oxygen, so you have less surface area absorbing oxygen. Your lungs have about a tennis court’s amount of service area. In other words, if you could open up your lung tissue and lay it out flat, it would cover a tennis court. So you have a lot of surface area, and you want to protect it.
Small particulate matter can also get into the bloodstream, which isn’t good.
The average adult breaths about 2,000 gallons of air each day. But on a bike, you're breathing deeper, harder, and faster, so there is more potential for getting that particulate matter deeper into the lungs.
If you see smoke, it's probably not a good idea to ride. These particulates can trigger asthma attacks, especially in kids who breathe faster than adults and take in more air.
Peggy:Is the damage permanent?
David: When you're younger, your lungs are still growing, so if you're not exposed to smoke for long periods of time, you can overcome it. But yes, the damage can be permanent. The scar tissue is not dissolvable.
Peggy:Do you ride when it’s smokey?
David: I've gone out when it's been worse than 150 on the AQI. From personal experience, if I start coughing, I just turn around and go home and say, the heck with it. It's just common sense.
Peggy: If wildfire smoke keeps you stuck inside for days, how do you train?
David:That’s why they have things like Zwift! And you put in a tighter filter in your air conditioner.
Peggy: What kind of damage does smoke do to our lungs?
David:First, people with underlying health conditions have a higher risk of lung damage from smoke inhalation. [But for all of us], when you have particulate matter going into the lungs, anything smaller than 2.5 microns can lodge in the lung tissue. It can cause difficulty breathing, coughing, runny nose, irritated eyes.
Particles lodged in the lungs are attacked by phagocytes, which try to engulf and digest the foreign particles.
If they can't kill the particulates, the body takes these cells and puts a hard coating around them, so the lungs actually get hard and are scarred. Anywhere the lungs are hard, they are stiffer and won't absorb oxygen, so you have less surface area absorbing oxygen. Your lungs have about a tennis court’s amount of service area. In other words, if you could open up your lung tissue and lay it out flat, it would cover a tennis court. So you have a lot of surface area, and you want to protect it.
Small particulate matter can also get into the bloodstream, which isn’t good.
The average adult breaths about 2,000 gallons of air each day. But on a bike, you're breathing deeper, harder, and faster, so there is more potential for getting that particulate matter deeper into the lungs.
If you see smoke, it's probably not a good idea to ride. These particulates can trigger asthma attacks, especially in kids who breathe faster than adults and take in more air.
Peggy:Is the damage permanent?
David: When you're younger, your lungs are still growing, so if you're not exposed to smoke for long periods of time, you can overcome it. But yes, the damage can be permanent. The scar tissue is not dissolvable.
Peggy:Do you ride when it’s smokey?
David: I've gone out when it's been worse than 150 on the AQI. From personal experience, if I start coughing, I just turn around and go home and say, the heck with it. It's just common sense.
Peggy: If wildfire smoke keeps you stuck inside for days, how do you train?
David:That’s why they have things like Zwift! And you put in a tighter filter in your air conditioner.
Stay in the loop with our weekly cycling stories.
