Take a hike - inside

Back in 2001, William "Randy" Weadon and his wife moved into a Virginia retirement community, and Weadon immediately began to gain weight. He became a Type 2 diabetic, dependent on increasing amounts of insulin every day.

"It was an entirely new lifestyle. You get everything done for you. There's a restaurant-style meal every evening," says Weadon, now 83.

One evening he had a severe hypoglycemic reaction, possibly from the combination of insulin and alcohol, or too little food. He awoke completely disoriented. "I decided then and there, I've got to do something," he said.

The next day, Weadon started walking the three-quarter-mile-long hallway of the community, a series of interconnected buildings in Springfield, after lunch and dinner.

"Three-quarters of a mile was about all I could do," he says.

That's no longer true. To say the least.

Weadon now walks seven miles a day, seven days a week, virtually every step of it indoors. When the retirement community held a pedometer contest in 2008, he walked an average of 32,000 steps (16.3 miles) each day for a week. Indoors.

His weight has dropped from 225 to 165, and he has weaned himself off insulin.

"I walk because I want to stay alive," he says. "I know I'm at risk for heart attack, stroke and loss of limb, being a diabetic. That's incentive for me to walk."

Excellent. But why indoors? What about spending glorious spring evenings and stuffy summer afternoons outside?

"Two reasons," Weadon says. "It's easier walking on carpeted floors. Being diabetic, I'm very careful of my feet."

And "it's just so easy walking around inside. I meet a lot of people. I know how far I walk. It's just so easy."