NOEL KING, HOST:
There's new evidence that cyclists may age better than people who don't bike. Their bodies seem to fend off some age-related decline. And we're not talking about Olympians. This is people who cycle just for fun. NPR's consumer health correspondent Allison Aubrey reports.
ALLISON AUBREY, BYLINE: Norman Lazarus loves to be on his bike. He's 82 now, and he's still at it.
NORMAN LAZARUS: I just like that wonderful feeling. I like the covering of the countryside. I like the feeling of your legs operating, your lungs operating.
AUBREY: Lazarus, who's also professor emeritus at King's College, London, says several years back, he became intrigued. He was not developing any of the old-age health problems he was expecting like bad joints or chronic disease.
LAZARUS: I realized that I wasn't aging in the way that I'd sort of been taught in medical school. You know what I mean? Like, I was expecting things to fall apart.
AUBREY: Instead, he was feeling fit and spry. And as he talked to fellow cyclers, many had similar stories. So together with a team of collaborators, he got a formal study underway. They enrolled 125 amateur cyclists, mainly in their 60s and 70s, people who were in the habit of biking about 60 miles over the course of a week. Then they compared these cyclists with a group of adults who did not exercise regularly. Here's researcher Janet Lord. She's director of the Institute of Inflammation and Ageing at the University of Birmingham.
JANET LORD: What we were looking at was every aspect of the body. So we looked at muscle mass and strength. We looked at bone. We looked at lung function, heart function and also the immune system.
AUBREY: Turns out the cyclists' muscle mass was better compared to those who did not exercise regularly. Maybe not too surprising. And their hearts appeared healthier, too. You could probably find the same results in other avid exercisers. Lord says the big surprise was how the decades of exercise seemed to influence the immune system.
LORD: We found that aspects of their immune system were also like that of a 20-year-old.
AUBREY: Take, for instance, the production of immune cells, called T cells. They're produced in a little gland called the thymus. With age, we make less of these cells, and the thymus turns fatty.
LORD: What we found in the cyclists was that they had as many of these new T cells just coming out of their thymus as a 20-year-old, which means they should be better protected from all sorts of infections.
AUBREY: The researchers didn't actually track how these cyclists responded to infections. Lord says they'd like to look at that in a follow-up study. And she says not all aspects of immune function were better among the bikers. So clearly it's not a panacea, but Norman Lazarus says the study does point to one more potential benefit.
LAZARUS: You can bet your cotton socks that exercise has a fix that we perhaps haven't been really aware of before.
AUBREY: It's another reason, Lazarus says, to keep moving. Allison Aubrey, NPR News. Transcript provided by NPR, Copyright NPR.