The other day I was moving along on a short run when five dogs, including a particularly toothy German Shepherd, came charging at me across their yard, and not in a ‘Hey, throw us a frisbee’-kind-of-way. It startled me more than a pack of dogs usually would (I suppose; a 5-dog assault hasn’t happened to me before) because I was spacing out about a strange conversation I had at a party the other night.

I was talking to another runner about marathons because, other than Weeds as a parable on suburban angst, that’s the only topic I ever speak to. He had never run one but was curious about training. I was in a post-mojito state of exuberance and perhaps overstating the life-improving qualities of the marathon when the runner’s wife said:

A marathon takes 7 years off your life.

Huh.

She said it with such conviction. Not the kind of conviction you would use if you had an advanced degree in exercise science, but the kind of conviction you would use if you were science itself. Despite the illogic of the claim, she was unequivocal. Everyone turned to me, but I was processing the suggestion that Dean Karnazes is looking at such a deficit, he might as well be six feet under and crawling with maggots. Or, alternatively, never conceived at all, depending on how metaphysical you want to get.

Given my post-mojito state, I think I smiled and responded, “Goodness, no!” to the woman, who is herself a runner training for a half-marathon. At first I wondered if she was playing the convenient-excuse card, but it seems more likely she was playing the my-husband-is-talking-to-you-about-marathons card. I resisted making a snide remark that by her count, I’ve lost 21 years of my life and am aiming for 35 years by May 2010, though in retrospect, it really would have been pretty funny.

Nor did I shoot back all the statistics and research that indicate, on average, running adds years to one’s life because I didn’t think it would be appropriate to get all scientific on her ass in her own backyard. There are plenty of studies arguing both the health risks and benefits of long-distance running, and I’m not going to itemize the findings here, except to say that the research indicates that heart damage caused by a marathon does not appear to be permanent. Anecdotally, however, several of my friends think marathoning has led to brain damage in me personally. If you want a very accessible review of the research, I recommend you check out Ben Cheever’s Strides, which has a fantastic chapter on the notion of ‘death by marathon.’

The thing that struck me was the silliness of the “fact” she asserted. I looked for studies that drew her conclusion–mostly because I’m about to drop another 7 years from my life in October–and I couldn’t find one. Who has ever read an obituary that states ‘marathons’ as the cause of death?

This is the question that popped into my head right before the German Shepherd charged me. Bitch. She and her pack stopped me short, and I backed into the street, unsure of what to do, other than yell at the owner to leash her dogs. I was standing in the middle of the street when a sedan crested the hill I was on and slammed on the brakes.

The people in the car asked if I wanted a ride to get away from the dogs, and to be honest I paused. My hesitation had little to do with the idea of hopping in a stranger’s car. It was an Infiniti, and I figured if they meant to imprison me, I’d probably get a Tempurpedic and a Wii, so abduction wasn’t my issue.

The issue: dog bite versus cheating on my mileage. It was a tough call.

But I got in the car (and added a quarter mile hill at the end; I’m that anal). So I guess Ms. 7 Years may be onto something about the health risks of marathons. She didn’t say anything about the point at which your expedited death will supposedly occur: in the race, after the race, or simply surviving dogs and traffic on a training run. This week, though, I’m thinking death by dogs is more likely than death by marathon.

But I still wish I’d made that quip about the 21 years.