Looking for the fountain of youth

Researchers say building strength and endurance helps the elderly stay fit in their golden years.

(CNN) -- The search for eternal youth often leads aspiring Methuselahs to experiment with growth hormones, nutritional supplements such as dehydroepiandrosterone -- better known as DHEA -- and melatonin.

Some elderly people also take mega-doses of antioxidant vitamins or injections of animal cells.

Such experiments can be expensive and yet ineffective, according to Dr. Elaine Cress of the University of Georgia Gerontology Center.

The center studies elderly people whose minds and bodies are strong, despite their age. Its lab is designed to mimic a home and tests patients' day-to-day abilities.

So, what is the secret to aging well?

Louise Cameron, 92, explains how she keeps her mind sharp. "I stay busy all the time and keep my hands and brain coordinating together."

She lives independently and holds a part-time job -- parking cars at football games.

When Cameron was born, the average life expectancy was 52 years. Today it is 77.

Professor Bill Slatt, 71, can leg press 540 pounds. Weight training, he says, keeps him fit and independent.

Researchers say strength and endurance are critical to stay fit in one's golden years. Also important: what and how the elderly eat.

Dr. Leonard Poon, director of the U.G.A. Gerontology Center, explains that the elderly should eat regularly, and include many vegetables -- especially greens -- in their diet. Keeping sugars to a minimum can also be helpful.

He adds that his most independent and healthy patients share similar personality traits. "They are very much actively engaged in what they are doing," says Dr. Poon. "They tend to be dominant -- talking about personality trait. They're in control of their lives, and they question information that is given to them."