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Exercising in Hot Summer Could Expose You to High Levels of Ozone

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Exercising in Hot Summer Could Expose You to High Levels of Ozone

Aug 11, 2017

If you live in Salt Lake City, you know it’s not a good idea to exercise outside during a muggy inversion. But did you know you should be concerned even on a clear summer day? Emergency room physician Dr. Troy Madsen explains how even though ozone isn’t visible, it can cause serious breathing issues. Learn the steps you can take to protect yourself this summer.

Episode Transcript

Announcer: Health tips, medical news, research, and more for a happier, healthier life. From University of Utah Health Sciences, this is The Scope.

Interviewer: In the wintertime, if there's an inversion, it's probably a good idea not to exercise outside. And in the summertime, you need to watch out for high ozone levels. Dr. Troy Madsen is an emergency room physician with the University of Utah Health. So that kind of surprised me that in the summertime, I got to watch when I exercise as well. Tell me about ozone and why I should be concerned about it.

Dr. Madsen: You know, you're exactly right. It's one of these things where we figure, "Hey, winter is over. I'm in the clear. I don't see that big, thick layer of pollution sitting over the valley. I'm good to go." But then we hit summertime and the high heat, and then we have this other thing called ozone. It's basically, again, a form of pollution. It forms when just the weather gets really hot so we typically see it on hot days here in Salt Lake City, so that's why it's an issue in the summer. And kind of like that winter weather, it gets trapped in the valley, we get the high ozone levels. Those are also going to cause problems for people in their lungs, particularly if you have sensitive issues like asthma or emphysema.

Interviewer: All right. So in the wintertime you can take a look and see what the particulate matter is. You can do the same thing online to see what the ozone level is for any given day. So if it's yellow or red, what types of things do you see in the ER as a result of that?

Dr. Madsen: So in the summertime, we very, very commonly see a lot of lung issues. It's something I find wintertime usually kind of hits late December as the inversion settles in, people start to come in that have a lot of lung problems, asthma, emphysema where things have flared up. And then there's this spike again in July.

Sometimes it's compounded by forest fires, and sometimes we get local fires or fires where the winds blowing that smoke into the valley. But typically, what will happen is someone who has asthma, who has emphysema, has thought, "Well, I've been outside the last few months. I felt great." They get outside with this poor air quality. It just causes things to flare up where their lungs get really tight, sometimes to the point where they really cannot breathe well at all and they have to come right into the ER.

Interviewer: All right. So if you have some sort of those issues, if it's a hot day in July or August and especially if there's been forest fires in the area, you might want to check that ozone level beforehand. What about healthy people?

Dr. Madsen: So healthy people, I can't say we see them quite as often in the ER. Some cases, I will see people who say, "You know, years ago I had exercised-induced asthma and just for the past couple of weeks, I've just felt really short of breath." And maybe they don't sound really wheezy when I listen to them, so we do other tests to make sure nothing else is going on.

But at the end of the day, I say, "Hey, maybe it's just that asthma that's kind of flared up a little bit with this air quality." But it's not like they really sick. It's more they're just saying, "Hey, what's going on?" Kind of diagnosis of exclusion, we say, "Well, maybe it's the air quality."

Interviewer: Yeah. So that's an interesting point that if normally you exercise and you don't struggle at all and then all of a sudden you're wheezy, you might want to check that ozone.

Dr. Madsen: That's exactly right. And that's probably where it surprises most people. They're thinking, "Hey, I've been exercising for months. I felt great. Now I'm having issues."

Interviewer: So no reason to go to the ER unless it's so bad, you're an asthmatic that you cannot breathe, and it will not release.

Dr. Madsen: That's right. I think if you can manage things at home okay, great. Get in to see your doctor if you need to try some additional medications to control things during high ozone levels. But yeah, if you start getting really tight, trouble breathing, absolutely. Get right into the ER.

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