WASHINGTON (States News Service) – To John Glenn, former senator and one of the best-known astronauts in history, NASA’s 1998 mission to study how a space veteran would deal with the extremes of space as an older man was a walk in the park.

"During flight, I never felt better in my life," said the 78-year-old Glenn Friday at a symposium on the experiments’ results in Maryland.

Glenn called the experiment -- comparing the process of aging to symptoms the body goes through in outer space – "a toe in the door" to understanding how the body gets older, and perhaps how to make the aging process easier.

"Daily exercise, simple as that sounds," he said. "I think too many people hit an age and they are expected to act a certain way."

At the two-day symposium, health scientists hailed the mission for paving a road to understanding bone, muscle and memory loss, as well as balance disorders and other age-related conditions.

Having pored over results from 80-odd experiments in space and life sciences during the STS 95 mission, scientists said the most striking discovery was that Glenn recovered from the trauma of spaceflight as fast as a middle-aged astronaut.

"The most significant finding for me in this mission, I think, is what did not happen," Glenn said.

Floating in microgravity is tough on astronauts’ muscles -- which take longer to recuperate from stress. Also, back pain and anemia are common. Bones become less dense and astronauts become light-headed.

But Glenn experienced no muscle atrophy, no decrease in muscle strength and no changes in the vertebral column, the scientists found, suggesting older people who are in good shape can participate in stressful activities like their younger counterparts.

"What is truly remarkable is we all would have predicted that it would have taken much longer for an older individual to adapt back on Earth," said Dave Williams, director of life sciences at Johnson Space Flight Center in Houston, Texas. "But he re-adapted to being back on Earth like an astronaut half his age."

Glenn also recovered a sense of balance quickly after flight, the scientists found. Williams said he hoped the experiments on Glenn’s balance provide information to help older people avoid falls.

What scientists don’t know yet is why Glenn fared so well, Williams said. Whether it was his genetic makeup, his fit condition or something else, is unclear from the one string of experiments.

Glenn, joking he would go back to space "tomorrow morning," said he would gladly take part in more such experiments. "We need a database of quite a large number – eight or 10 … This is just a start."