If you see people in motion, faces grotesquely screwed up into pained expressions, hoofing it along Memorial Drive and Allen Parkway today, don't be alarmed. Our paltry public transportation system is still up and running, and no, everyone's vehicles did not suddenly break down en masse.

Those individuals voluntarily putting pads to pavement are most likely observing National Running Day, where participants fool themselves into believing that 15 minutes of sweating in their Sportivas once a year will satisfy their fitness quotient.

Err. Did we say that out loud?

We meant that National Running Day is "a national initiative of the major organizations within the running industry to join forces in an unprecedented, unified effort to nationally promote running as a healthy, easy, and accessible form of exercise." Doesn't running sound pretty now?

It's fairly undisputed that running has marginal (all right, considerable) benefits to human beings. But what about the effect on the earth? We all know what happens when you get on Mother Nature's bad side. Is running good for her, too?

It turns out, not really.

Popular belief trends toward runners being the athletes most concerned with the environment. And the impact of runners on their realms is small, right? Runners certainly don't drive to workouts, fly to exotic race destinations, and launder their expensive, limited apparel on a regular basis.

Oh, wait a second. When you think about it, that's one filthy carbon footprint those pesky runners leave behind.

And don't even get us started on the shoes.

"Many runners think of their sport as simple and nature-friendly," Florence Williams wrote in a Runner's World story. "We don't need fancy equipment to do our thing — we mainly need strong legs and lungs, and the will to keep moving."

But that's where the eco-harmony ends. "We do require shoes, lots of shoes," Williams continues. "And alas, the shoes are made of plastic, the kind of plastic that the human race engineered to last for a thousand years. As plastic. With a few rare exceptions, our shoes are made exclusively from heavily processed crude oil. We're wearing a gusher."

Yes, "a gusher." Toxicity incarnate. Biohazards. Noxious emissions. Pollutants. A pair of congealed oil spills. And runners swap these weapons of grass destruction out every few months!

We're not going to tell you to stop running. But maybe, this National Running Day, we're telling you not to even start in the first place. Use the heat as an excuse and coast through the summer months, at the very least. That's what air-conditioned houses and couches are made for, aren't they?

Now if you'll excuse us, we have to get to Memorial Park. You vacating the trails frees them up for those of us who put our selfish health interests before the environment, and enjoy every fat-burning minute of it.