He and his wife now have a dog, and walking it twice a day for 20 to 25 minutes is part of his daily exercise routine.
He also makes sure he gets up from his computer at work several times a day and takes a brisk 30-minute walk.
Today he weighs 195, he says proudly. "It's been nine years and I've kept it off. And walking is a big reason why."
Genter didn't join a gym, hire a trainer or buy an exercise machine. He just walked.
So how do you get started? Slowly.
"Don't set a really large goal. Set a small one first, like walking one block, then gradually add on to that," suggests Sharon Brangman, M.D., chief of geriatric medicine at SUNY Upstate Medical University in Syracuse, N.Y. Her patients are all over 65, many in their 80s and beyond.
"I've had women in their 70s who tell me they feel sluggish and can't lose weight even though they eat like a bird," she says. But once they start walking daily, "they sleep better, feel better and even lose some weight. One woman told me, 'I don't know why I didn't do this before.' "
Start with a short walk, even five to 10 minutes, and gradually increase to 30 minutes five days a week. "And it doesn't have to be 30 minutes continuously. You could even split it into three 10-minute walks during the day," says Bushman, who is also editor of the new American College of Sports Medicine's Complete Guide to Fitness and Health.
Just be sure to check with your doctor before you start any exercise program, especially if you recently have been inactive or are substantially increasing your activity level.
Also of interest: Exercise tips for boomers. >>
Candy Sagon writes about health and food for the AARP Bulletin.