Science Wednesday: Exercise? Oh yeah

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By Susan Stone

Do I need to exercise? You bet. We all do, because exercise is so important for health. I especially need to exercise to get my weight into a healthy range. That additional weight, and my mild asthma, puts me at greater risk from air pollution. And eventually, my age will add to that risk.

People with asthma are at greater risk from exposure to ozone. It can cause difficulty breathing and make them more likely to respond to asthma triggers, like pets, that may not normally cause a reaction. Particle pollution can aggravate asthma, too. It also can trigger heart attacks, stroke and irregular heart rhythms, all of which I want to avoid. And the risk of a heart attack or stroke starts to go up at age 45 in men and 55 in women. So I want to minimize my air pollution exposure, for several reasons. But I really need that exercise at the same time.

Figuring out how to get that exercise and reduce exposure to air pollution can be a challenge. So checking the Air Quality Index (AQI) has become part of my daily routine.

Here’s what I do. I love to take walks in my neighborhood. It’s a pretty walk, with hills and a pond. My normal route is a couple of miles in the shape of a figure eight. The middle of the eight is closest to my home. On days when ozone levels are high, I’ve noticed that sometimes I get what feels like a stitch in my side that makes breathing painful. It doesn’t go away even when I get warmed up. So when ozone levels are high, I take it easier. If I get to the midpoint of the figure eight and feel good, I keep going. If the stitch in my side is there, I pack it in and go home or exercise indoors.

Ozone levels typically are lower indoors, but particle levels can be high even inside. So if the AQI indicates that particle pollution levels are in the unhealthy ranges, or if I smell smoke, I’ll go exercise at a gym, or take a walk through the buildings at work. But even though I’m indoors, I take it easier and pay attention to any symptoms.

Exercise? Oh yeah. It’s important for good health, and it’s a great stress-reliever. And with a little planning, you can exercise outdoors, even if you’re considered at greater risk from air pollution. Even if you’re not, check the AQI every day. It’s a healthy habit.

About the author: Susan Stone is an Environmental Health Scientist and likes to walk in her neighborhood every day, weather permitting. She checks the AQI on her computer, but you also can download a free app for iPhones and Android phones. Visit Airnow to find out how.

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