PHOENIX (3TV/CBS 5) -- Most people call it quits and head into their retirement when they hit their mid-to-late 60s.
A brain research professor at ASU's BioDesign Institute, 91-year-old Dr. Paul Coleman has kept working well past that age and is still going.
Needless to say, his retirement plan is different from most.
"Whenever I feel an urge to exercise, I lie down until it passes," Dr. Coleman says jokingly.
He has a great sense of humor, and knows his stuff, especially when it comes to the workings of the brain.
"I research the brain and brain-related neurodegeneritive diseases particularly Alzheimer's disease," Dr. Coleman says.
He's been in this field since 1975.
"We've learned a lot but not enough. We know Alzheimer's disease starts many decades before it's clinically diagnosed. The very earliest symptoms of Alzheimer's can be picked up in people now in their late teens and early 20s.," he says. "We no longer talk about curing Alzheimer's disease. What we talk about is detecting it early and then intervening at this very early stage so people can live the rest of their lives having the disease but not having symptoms."
After 50 plus years in this field, Dr. Coleman remains very energized about the work he does everyday. So, when does he plan to retire? Well, never.
"I want to pass out, pass away at the lab bench, clutching my computer," he says with a chuckle.
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Until then, age doesn't really seem to be a factor for this guy. He's newly married to a beautiful woman for the last two years. When he's not working, he enjoys sailing the open seas.
Dr.Coleman has advice on living and loving life.
"Do what you think will make you happy, and thinking about my kids and grand-kids, I don't really care what they do as long as, at the end of the day, they can say, 'I enjoyed doing this,'" Coleman says.
Dr. Coleman recently developed a blood test that will detect Alzheimer's at an early age. He reports to the lab every single day.