We’ve had very hot weather in Spokane lately. A local airport, Felts Field, recorded ten straight days of highs over 90 degrees, and one day it was 107 degrees (42 C.). This raises an important safety question for runners: When running in very hot weather, what is the most common way that runners end up dead?

If you answered heat stroke, good guess, but wrong. The correct answer is heavy sweating stings the eyes so badly runners can’t see well, they go off course and plunge thousands of feet off a sheer cliff.

I lived in southern Japan for a couple years, which has a summer climate similar to the Midwest. The hot and very humid weather causes heavy sweating and low evaporation. Here’s a photo in which I re-created a finish to one of my runs in Japan.Honestly, I was soaked as thoroughly as if I’d jumped into a pool. Before going inside my apartment, I’d remove my shirt and wring it out over the railing.

Because Spokane’s dry climate allows greater evaporation, I don’t get totally soaked like in Japan, however I do sweat heavily. I often use sunscreen, and that makes it even worse on the eyes.

For those of you at high risk of heavy sweating and cliff-plunging, here’s a solution I pioneered that keeps perspiration out of the eyes.

Though sponges are cheap, I use the same one for washing my car. And they’re great at cushioning the blow whenever you run into something.

So, don’t let the summer heat stop you from getting in a run!