The Good Life: Extreme Exercise the 'Anti-Aging Pill'

VIDEO: New generation of retirees taps into its athletic
WATCH Baby Boomers Get Physical

Ernestine Shepherd does 60 reps a day to build biceps that have won competitions. She does 60 reps a day to strengthen thighs that have finished marathons.

Shepherd spends hours every day lifting and running, stretching and toning to maintain a body anyone would envy. The catch: Shepherd is 75 years old.

"I have to say, I feel about 45," she said.

Now the oldest competitive bodybuilder in the world, Shepherd has raced in nine marathons, won three bodybuilding competitions and made the Guinness World Records.

Shepherd is an extreme example, but all over the country older Americans are turning to competitive sports. Dr. Michael Joyner, himself a marathoner and exercise expert at the Mayo Clinic, says traditional limits are gone.

"We are seeing a trend for baby boomers and older people to participate in intense physical activity and physical sports," he said.

The mindboggling transition from self-proclaimed "couch potato" to the embodiment of fitness began 20 years ago for Shepherd. She was in her mid 50s and was dissatisfied with her body after going bathing suit shopping with her sister, Mildred. The two started working out together, but a few years later Mildred died. Today Mildred continues to inspire Shepherd.

To say Shepherd's workout regimen is strict would be an understatement. The day begins at 2:30 a.m. with a 10 mile run, which is followed by a breakfast of raw egg whites. Then its off to the gym for a few more hours of exercise: She does 300 sit-ups, makes leg pressing 225 pounds look easy and even teaches a class.

"I think there is pretty good evidence that fairly intense physical activity in middle age, and even as you get to be 65 or 70, does slow down the aging process," Joyner said. "What I see happening ... is that you almost become a teenager again. ... The other thing that happens is your motivation becomes maybe a little bit purer. It's less about beating the other person, and it's really improving yourself and testing your own limits."

Something Shepherd has known for years.

"If there were ever an anti-aging pill, name it exercise!" She said.

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