"The sweat was pouring down my back, my feet were sore," my friend Evan was telling me. "I was ready to drop from exhaustion when the timer on the treadmill finally hit 30 minutes and started to slow into cool-down mode.

"It's OK," he continued. "I'm trying to stay fit and lose a few pounds, and for that, you have to put in a little effort. So I looked at how many calories got burned during that burst of willpower. The machine said 150. 'That can't be right,' I thought. 150 calories for all that effort? There's something wrong here -- we burn 60 calories every hour just sitting in front of the TV. How can a half-hour on the treadmill do so little? I'm putting out 10 times the effort and getting two times the result. No wonder people don't exercise more."

"You know what they say," I told him: "'You can't be too rich or too thin.'"

"Sure, you can be too thin," he said. "Haven't you ever heard of anorexia?"

"Don't nitpick, you know what I mean."

"No, I don't. People can die from being too thin. That's not nitpicking. I wonder who would say such a thing? Are they speaking from experience or are they just trying to sound clever?"

"Man," I said, "Don't overthink it. It's just a saying. It's not written in stone. So, OK, you can be too rich and too thin. Are you happy now? Can we move on?"

"No, it's only the 'too thin' part I'm talking about. Of course you can't be too rich. Who wouldn't want to be too rich? I'm just saying that you can be too thin."

"OK, fine. You can't be too rich. I don't know, it just isn't that quotable. I was trying to be motivational."

"You have been," Evan said. "You've motivated me to find new, smarter friends."

I'm glad I didn't say "No pain, no gain." He might have bitten my head off.

But Evan had asked one good question: Why don't more people exercise? It's odd that with all the stories about health and fitness we see and read, we continue to become even less healthy. We watch the Olympics for inspiration; we watch tons of basketball and football and tennis. And the obesity rate goes up. Every magazine and newspaper we buy has stories about cooking healthy meals, and still the obesity rate goes up.

With all the cooking shows on TV telling us how to use more fresh fruit and vegetables, it doesn't help. Magazines still run the same "How to Lose 20 Pounds by Next Tuesday" they've been running since the invention of the printing press, and we get heavier and heavier.

And, unless you're planning on amputating a limb, it is highly unlikely you'll drop 20 pounds between now and Tuesday, no matter what you eat. It took me a year to lose 20 pounds and one pant size. The hard part, it turns out, isn't running on the treadmill. The hard part is finding the time, getting to the treadmill, and doing it again and again and again, every day.

Soon, it became a habit that was hard to break. I felt badly if I didn't go to the health club and do something -- swim, lift weights, stretch. I like to listen to audiobooks while I'm working out, so I'm not just exercising, I'm enjoying a half-hour of a best-seller that I wouldn't read otherwise. Sometimes I run a little further just to finish a good chapter. I don't dread getting on the treadmill or walking outside anymore; I've come to like it.

What I really enjoy about exercise is the money I'm saving. I figure each year of exercise has probably saved me a few days in the hospital. Even with the best insurance, a short stay would cost much more than my yearly health club membership.

The real surprise is why my insurance company doesn't pay me to go to the gym. It'd save them a fortune.