Matthew Inman and I are halfway through our five-mile run in Carkeek

Matthew Inman and I are halfway through our five-mile run in Carkeek Park when he suddenly stops. “Ooh! Salmon, look! Wait, are they dead?” There in a stream beside us, two tired fish are floating languidly against the current. “Oh, no, they aren’t dead, never mind,” he says, sweat dripping down his forehead as he excitedly leans over the wooden railing on the trail. “Anyhoo, the solid ones are the females and the striped ones are the males. They swim upstream and lay their eggs in the soil, and then, well . . . they die. It’s pretty cool.”

This is one of Inman’s favorite things about running in Seattle—the poor-man’s-safari element. As he writes in The Terrible and Wonderful Reasons Why I Run Long Distances (Andrews McMeel, $16.99), his latest cartoon collection from, “You can see the wilderness, you can see the cityscape, maybe you’ll see a rainbow, maybe you’ll see a caribou taking a dump. Whatever you see, you are mitigating monotony.”

Inman and I aren’t that dissimilar from the salmon. Just as these fish are programmed by biology to endure pain and suffering over incredibly long distances, we long-distance runners have to run. We’re compelled. It’s the only thing that makes us feel better—even though, paradoxically, it sometimes feels terrible.

“Running for me is pain on tap,” says Inman as we pick up the pace again, breaking away from the salmon to start a quick climb up a dirt hill. “It’s a little spigot you can turn on to hurt yourself. And because of the way it works for me, it’s also bliss on tap. Any day that I want to, if there’s a million things weighing down on me—like, I need to do laundry! I need to answer 10,000 e-mails! I need to finish this comic ASAP!—I can just put that crap on hold, go hurt myself on a run, and suddenly I’m flooded with joy, even though all I did was sweat and grumble for 30 minutes.”

In the midst of training

for this Sunday’s Seattle Marathon, Inman’s book came to me like a shining beacon in the nippy early-morning fog. I can’t relate to most writing about running. I don’t really care about the training regimens, diets, or mile splits of the world’s elite runners. I run because it makes me feel as if I have some control over my messy life—a concept Inman lays out brilliantly in one of the book’s more genius panels.

Standing in the middle of his disgusting, disheveled kitchen (vodka, a stained sock, and an eviction notice strewn on the counter), a haggard-looking Inman sips from his water bottle. The thought bubble above his head reads “I went for a run today. I’m such an overachiever.” (Behind him, a raccoon sneaks a tortilla chip from the bag atop his sink of dirty dishes.)

Running, Inman writes, “enables me to feel like my life is rocketing skyward, even if it’s going straight to hell.” He’s a runner/philosophizer for those, myself included, who’ve run more than one race with a hangover.

Until somewhat recently, Inman’s legion of online fans might not have known he was a runner. The Oatmeal is relatively new. Launched in 2009, the site now receives 30 million page views a month. But Inman, formerly a Web designer and developer by trade, is a veteran of the roads—he’s run some 40 half-marathons, five full marathons, and an ultramarathon. As he says of his other cartoons, “My work isn’t usually very personal. It’s about proper semicolon usage, marine biology, or bears with giant nards or something. The running comics were harder to write for that reason: It was a little more on the personal, spiritual side for me.”

In that spiritual realm resides The Blerch, a blobby, fat cherub Inman draws with insect wings—a symbol of all the forces that would keep him sedentary. The Blerch is constantly hovering over Inman’s shoulder in the comic, sometimes sweetly, but often angrily—ordering him to sleep late, eat as much cake and chips as possible, and watch RoboCop and Gladiator on his iPad all day. The Blerch embodies a slothful past Inman wants to leave behind, he explains. “I run because it’s the only way I know how to quiet the monster,” Inman writes. “I run because deep down, I am the Blerch.”

Having scored a New York Times bestseller with his prior How to Tell If Your Cat Is Plotting to Kill You, Inman wasn’t sure if The Oatmeal’s fans would embrace such a personal strip about running. The Blerch lived only in his head for years before he finally drew it. He needn’t have worried. Instead of doing a conventional author tour to launch the book in September, he hosted fun-run book signings across the country and a “Beat the Blerch” 10k/half/full marathon race in Carnation. The race sold out in minutes. Inman had to add an extra day to accommodate the 4,000 runners who signed up. Now he’s planning more Blerch races around the U.S. next year.

“It was kind of surreal for me, because it’s like, here’s this fat little cherub I drew in my basement,” Inman laughs as we crest a hill, “and suddenly people are cosplaying as him running in this real-life massive, sweaty marathon that came from my drawing.”

Oh, shit—the marathon on Sunday! Due to a recent cycling accident that roughed up my quad, I tell Inman I had to stop training until the swelling went down. Our five-miler is the first run I’ve done in a week.

“Jesus, that sounds terrible,” says Inman. “But I mean, you should be tapering now anyway, so that actually might work out for you.”

During his September marathon in Carnation, I ask, was it sort of shamanistic to run as the Blerch? There Inman got to embody his personal demon, in costume form, and overcome it.

“You know, the weirdest, most magic thing about the whole episode has been the stories other runners tell me,” he says. “I’ve met more people than I can count in the year and a half since that first Blerch comic came out online who started running because of it. I met one guy who had lost 80 pounds after starting to run because of that comic.”