I was running on the Mall one beautiful evening a few weeks ago, when I was nearly stopped in my tracks by a big yellow sign: “We’re Hiring.”

In this economy, the sheer novelty of a private-sector job offer can stun you to a standstill. But when I realized that the prospective employment came from National Pedicabs, one of three companies whose drivers traverse parts of the city, I had a true epiphany.

These guys would pay me to ride a bike all day? Could this get any better?

Pedicab drivers, like their renegade cousins, bike messengers, burn countless calories cycling, one of the most healthful forms of exercise we know. They work outdoors. They work for themselves. They set their own hours. A hustling driver can cover 25 or 30 miles in an eight-hour day, earning about $200 and staying pretty darn fit in the process.

Jason, whom I met when I answered the National Pedicabs ad, says he dropped about 20 pounds when he began working weekends taking tourists to monuments and other points of interest. (He works for “the government” during the week, he said, and didn’t want his last name included here.) Another middle-aged driver told me she goes to the gym a lot less during the months she pedals folks around the Mall.

“I like being outside,” said Tom Folkes, a 55-year-old pedicab driver. “I like the exercise. I’m a lifelong cyclist.”

They have formed a small community, a subculture of about 100 independent-minded souls who hold a variety of jobs during the week or pedal full time. Jason calls them “ethical gypsies.” One young man who told me he has been driving a pedicab for several years said he considers himself “semi-retired,” at least “in my head.”

Folkes is a Web site developer who is working on an artificial intelligence project. He says he once worked for NASA. He also has a dog-walking business and pedals tourists around the Mall when he pleases.

“Developing software is a very introverted activity,” Folkes said. “I’m obviously an extrovert.”

It took Jason about two hours to teach me the basics of the pedicab trade and for me to stop overreacting to every bump and undulation of Washington’ s battered roads by careening into the curb or veering into another lane. Once he was reasonably assured I wasn’t going to kill myself or my passengers, Jason set me free behind the National Museum of Natural History where drivers often wait for fares.

That’s when I began to understand why everyone isn’t a pedicab driver.

Pedicabs are heavy. Really heavy. The contraptions themselves weigh about 150 pounds. Throw in an additional 500 pounds of cornfed Iowa tourist and, even with 21 gears, moving a pedicab takes serious effort, at least for a beginner like me. It’s not bad on level ground, but even the slightest rise is cause for concern.

Sweat ran in rivulets down my face, dripping on the bike, as I pulled Jason, who weighs 235 pounds, up the modest hill from Pennsylvania Avenue to the company’s depot at Ninth and M streets on my training ride. By the end of the evening, I had soaked through my T-shirt and the bright green “National Pedicabs” shirt Jason gave me. I drank a 22-ounce Ga­tor­ade and several bottles of water in about three hours.

Pedicab drivers rent the bikes from the companies that own and maintain them; had I really been employed, that Saturday would have cost me $50. Technically, drivers work for tips. A fare that roughly boils down to a dollar a minute is negotiated before passengers get in, but there is no set price. The drivers long ago figured out how much is worth their while.

When you subtract the winter months, rest days, bad weather and other impediments, Jason said a full-time pedicab driver can earn $15,000 to $18,000 a year, tops. Do they declare all that cash on their taxes? I didn’t ask. I don’t know which federal agency Jason works for, and I don’t need an audit.

My first fare was a family from New Jersey, here for the Baltimore Ravens game and other events. We talked football all the way down Constitution Avenue to the Lincoln Memorial. They were good sports as I weaved my way from the curb into the right lane and back again, as Jason had instructed me, and paid me the $25 we had negotiated, despite an alarming moment or two.

When I took a couple from Madison, Wis., back from the Lincoln Memorial to the Federal Triangle Metro stop an hour later, I adopted a different strategy, staking out the right lane and refusing to move over. As I sauntered down Constitution at about five miles an hour, cars zoomed past me on the left and right. I think my passengers were a little unnerved, but we chatted amiably about Washington and the 9/11 events planned for the next day.

Traffic, even taxis, is not the threat you’d think it is. The bane of pedicab drivers’ existence is the U.S. Park Police, with whom they seem to skirmish daily over where, and whether, they can pick up fares on the Mall. Drunks are another annoyance. Some drivers told me they won’t work lucrative Nats games or the U Street corridor so they don’t have to put up with people who’ve had a few.

I turned in the pedicab around 7 p.m., gave my $45 in earnings to Jason, and went home to spend the rest of the night massaging cramps in my toes, feet, calves and thighs. There probably are easier ways to make a living, and to stay in shape. But perhaps not at the same time.

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