We all know that mental and physical activity is good for our health, but did you know that the more active you are, the longer your life expectancy – and the sharper your mind?

Studies by the Archives of Internal Medicine have shown that sitting unstimulated for prolonged periods of time could reduce your life expectancy compared with your more physically and mentally active peers. In a study of 220,000 people, individuals who sat for more than 8 hours a day were 15% more likely to die within the next 3 years than those who only sat for 4 hours a day.  Another study showed that moderate levels of physical activity increased life expectancy by up to two years – and that high levels of physical activity increased life expectancy by up to four years.

Maybe that’s why someone like Helen Deneka is as sharp and active today as she was 40 years ago.  At 87, Helen Deneka could very well be the nation’s oldest working nurse.  Now with over 7 decades of nursing experience, Helen works full-time at the Outpatient Surgical Center of Baptist Memorial Hospital in Covington, Tennessee.  Born in 1925, she gained interest in the field while taking care of family members when they were sick, then enrolled in a nursing program at Baptist Memorial Hospital in Memphis, TN, in 1943 – at the ripe old age of 17.

70 years later, she has seen and worked through remarkable changes in professional medical care, including the introduction of penicillin; installation of air conditioners, patient telephones and bathrooms in hospitals; and impressive advancements in medical technology itself.

“Back then, we did everything by hand,” Deneka says. “Checking the pulse, taking blood pressure…We used to wash all the syringes and needles between patients and sharpen our needles with a whetstone.  Now they throw everything away.”

The changes in technology haven’t slowed Helen Deneka down one bit.

“I do the paperwork, then start the patients’ IVs,” says Deneka, describing her daily routine at the outpatient surgical center. “Fortunately, I get them on the first stick 99 percent of the time.”

“She never sits!” says fellow nurse Margaret Green, 66. “She’s going all the time…She’s such a caring and conscientious person.  I can’t imagine her retiring.”

Whether or not genetics play a role, there’s no question that the daily physical and mental stimulation help keep Helen Deneka’s mind sharp and her body fit.  In an era where early retirement is a popular goal – yet health care costs keep going up – perhaps we’re approaching old age the wrong way.  Maybe ceasing to work isn’t the ripe fruit we imagine it to be; maybe we should look at retirement as not so much “stopping working” as shifting to work that stimulates and enriches us, even if it doesn’t pay as well.

As for Helen, does she ever plan to retire?

“I’m thinking about it,” she says, returning to her charts. “But not today. We have a lot of patients coming in.”