When you're training for an endurance event, you can't really stop running because of excessive heat or bad air. While I have access to a treadmill, there's nothing I hate more than having to get in a workout that way. So this week, that has meant doing what I can when I can do avoid doing more damage than good.

I'm training with the Leukemia and Lymphoma Society's Team in Training to run a half-marathon Oct. 19 in San Francisco. When the air or heat gets really nasty, our coach adjusts our schedule. This past week, I ran early on Tuesday and Thursday, avoiding the hottest part of the day.

Still, even that early in the day, the air just seems toxic. Yesterday I had the worst run I've had in months and have felt generally cruddy ever since. My husband meant to go 9 miles on his last run, but decided to cut it short at 6 miles for the same reasons.

Even with the unhealthy air and warnings from health officials to avoid outside activity, I see people running, getting in their miles, even in the hottest part of the day, when I'm driving home from work.

It's a dangerous choice. Earlier this week a respiratory expert told the Bee that he was telling his friends, even those who don't have respiratory problems, to stay inside as much as possible. The heat of the Valley is something we've learned to live with. The air quality problems we have right now are a different story.

Exercise has a lot of benefits, but right now exercising outdoors is just not smart.

(Photo by John Walker/The Fresno Bee: The view north up Blackstone Avenue from the Fresno Pacific Towers building through the layer of bad air Friday afternoon.)