I was in Beijing a few weeks ago for work, and I took this picture from my hotel. This is what 203 Air Quality Index (AQI) looks like. This is known as “Very Unhealthy” on the AQI charts. Running in pollution like this is dangerous—we’ll discuss why today—but fortunately I knew how to minimize the negative health effects. I had to be smart about it. I was no stranger to running in air pollution since I’d lived in Taipei, Bangkok, and Beijing itself. In fact, it’s a way of life for most people living in the major cities of south-east Asia: I remember the average AQI being 70 almost every day in Taipei. Regardless, I would routinely go running in this pollution—80miles/130km/week—and so I had to be as smart as possible to mitigate the negative health effects. I needed to run and get good workouts in, but I didn’t want to compromise my health. So, I came up with three “tricks” to make running in pollution a little healthier for myself, and today I will share them with you.
But first, what are the health effects of air pollution? Why is it bad to exercise in air pollution anyways? Does running in air pollution actually cause problems? In short, yes. I’ve made a quick summary of the research I’ve come across (sources linked below):
- Increase in respiratory disease 
- Increase in cough, wheezing, and lower respiratory tract infections (more-so in children) 
- 0.4% increase in non-accident mortality 
- 0.63% increase in mortality due to CVD 
- 1.393mmHg increase in systolic blood pressure 
- 0.895mmHg increase in diastolic blood pressure 
My personal favorite:
“Each 10 μg/m³ m^3 elevation in fine particulate air pollution was associated with approximately a 4%, 6% and 8% increased risk of all-cause, cardiopulmonary, and lung cancer mortality, respectively.” 
Great. So, if these are just results from living normally in air pollution, then I think we’ll all concur that running in air pollution is bad for us.
What exactly is happening, on a physiological level, to cause these adverse health effects? We need to look towards the lungs:
Inside of the lungs, we have the alveoli. These little alveolar sacs look just like a bunch of grapes. On the inside of these sacs, we have de-oxygenated blood. On the outside of these sacs is the air that we breathe. The skin of these sacs is extremely thin—just like the skin of a grape. So thin in fact, that oxygen molecules can pass through the membrane, into the capillary beds that permeate them, and oxygenate the blood. Beautiful.
With air pollution, PM2.5 is the main culprit that leads to bad health effects. PM2.5 particulate examples are: dust, ash, and soot that comes from the combustion of solid & liquid fuels (i.e. coal, heating, engine exhaust). These particulates are 2.5 microns or smaller (one 400th of a millimeter). So small in fact, that they can pass through the alveolar membrane and into the bloodstream. Gross. PM10 is also a culprit as well. These two—PM2.5 and PM10—make up the AQI (Air Quality Index) mentioned earlier.
What can runners do about it?
So the health effects of running in air pollution are…not desirable. But if you’re traveling through a major city for work, and want to—NEED to—go for a run, what do you do? What if you live in one of these cities, does this mean you are doomed to respiratory diseases? Thankfully, no. I made a YouTube video while I was in Beijing on the “3 Ways to Run in Air Pollution: 200+ AQI”, so if you like your content in video-form, just watch below. I thought it would be a nice touch to be talking about it whilst being in the belly of the best, so to speak.
If you don’t have time for a beautifully produced YouTube video, don’t fret. Below are the tips that I cover in the video. Also, it’s important to note that I did not approach this as avoiding running outside. I could easily say, “Run on a treadmill.” or “Go the pool and do some laps.” That’s too simplistic. I’m not interested in avoidance, and I’m sure you aren’t either. I’m purely interested in being able to do the activity that I love, WHERE I love to do it (outside): but I want to do it as healthily as possible given unhealthy circumstances. You probably do, too. I lived in high pollution cities for 2.5 years and I easily ran more than 5000 miles (8050km) during that time. These were the best ways that I went healthily running in air pollution:
1. Run in the Morning
I’m not a morning person. I love to sleep. This being said, if I have an important workout on the schedule, I’ll make an exception: I wake up before the cars do. A large portion of PM2.5 will come from exhaust (cars, trucks, buses, scooters, etc.). Typically early in the AM around 6-8am there will be less pollution in the air, because there has been less traffic for several hours prior. Go figure there are less cars on the road from 2-6am than from 2-6pm. Anecdotally, I’ve noticed that Saturday & Sunday mornings are the cleanest, or likewise on a day when there’s a major holiday and people have off from work.
2. Wait for the Wind
If possible, see if you can plan a workout when there will be a bit of storm: the wind will blow away the air pollution. Check out www.aqicn.org and you can see an ‘air pollution forecast’ over the next few days. It might be a pain to rearrange a workout and plan around the weather, but it’s better than inhaling diesel fumes on your next VO2 max interval session!
3. Wear a Pollution Mask
This strange man is either: a) Bane, or b) Myself wearing a pollution mask. Ha-ha. Wearing a mask during a run isn’t the most enjoyable thing, but if you happen to get caught in cloud of smog, a pollution mask will work in a pinch. I’d say that whenever I wear a mask during a run, my breathing is 15-20% harder than normal. I do, however, immediately notice a difference in air quality when I take it off and on. In a heavily polluted city like Beijing, it’s genuinely as striking as moving my nose away from the back of a car’s tailpipe and into a set of fresh lavender-scented sheets. The difference is night and day.
I was curious as well: do the pollution masks actually make a difference from a health standpoint? Can they actually reduce the air pollution entering my lungs? Which one is the best for running? I did a bit of research (also discussed in the video below), and it turns out that YES pollution masks can absolutely help reduce the adverse health effects of poor air quality, BUT they need to be of a certain type and have certain characteristics. N95 masks, Respro, Vogmasks, or carbon filter masks are some of the most common, but research has actually shown some may not be as effective as you think. There are two main considerations when choosing masks:
- Filtration of fine particulates (PM2.5 & PM10). This one is obvious: does the pollution mask filter out the harmful particles?
- Breathability: Can you breathe easily with the pollution mask on? A gas mask would work wonders for PM2.5, but it would make running a tempo run significantly more challenging. We need a mask that allows that sweet O2 in, but still catches the bad stuff.
It turns out—after exhaustive research, linked below—that the best type of pollution masks are:
Nanofiber masks, multilayered and made from electro-spinning.
They will have 90%> filtration as opposed to disposable non-woven masks (i.e. the cheap ones that come hundreds to a box), but also a high air permeability which will allow easy breathing while running. The study is interesting, so I’d recommend checking it out. The N95 or N99 masks that we’ve all seen before at construction sites are great at filtering PM2.5 (>80%), but breathability is harder. I can personally attest to this: running with an N95 mask made it about 15-20% harder to breathe. So, these N95 masks are good, but not great for running in pollution. Certainly not amazing. I think the reason for this difference in breathing ability is quite interesting:
Notice how the Nanofiber mask on the right has a tighter weave but thinner threads. And on the left, the cloth-based mask has thicker threads and is much more porous. They both will catch roughly the same amount of particulates, but the thinner nano-threads will make it easier to breathe. Awesome!
I haven’t tried them yet, but I’m excited to.
So there you have it! Air pollution causes, air pollution health effects, and if you must go running in air pollution, how to schedule your training appropriately and be as healthy as possible.
If you want to see me running the streets of Beijing, checkout my video below! Don’t forget to Like & Subscribe to show some love 🙂