I'm 52 (53 in November). I've been riding around 5.5 years. Did lots of gym stuff before that, since I was about 25. I also was the last one chosen for any team in gym class. But, the one thing that i did do on a pretty consistent basis was ride my bike. I didn't learn to ride until i was 10 (too uncoordinated), but once i did, I was rarely home. I had a Schwinn with coaster brakes and 2 three speed Raleighs. Had a huge generator light on the front of one of them. I lived in a suburb of Boston that had lots of hills... now I can't believe i went up them on a 3 speed. Well, moving to Florida and then Arizona near the end of high school pretty much stopped the riding. Too hot and everyone drove everywhere. I did a lot of walking in AZ, along with the gym stuff, but somewhere along the way, a boyfriend bought me a 5 speed road bike. I used to ride it to grad school classes in summer school, when i first started teaching. I have a distinct memory of riding in a sundress with a backpack on! A few years later, my husband bought us 12 speed bikes. I rode a little, probably never more than 10 miles, at a very slow speed. That ended when I was 7 months pregnant and I stopped short, behind my husband and the down tube shifter went into my stomach. I went into premature labor, but all ended well.
I started riding again because my husband got me into it, along with one of my sons. I do feel pretty young when I'm riding, although I think I need to take a few more rest days than I do! A funny story that happened this year was one day when I was chaperoning at science camp last December, i went on a short, but steep hike up a snowy, icy trail with the other teachers (the oldest one was 34). A couple of weeks later, one of them, who is about 25, told me that they "all want to be like me when they get old..." I knew it was a compliment, but it didn't sound right.

By the way, the sixties were cool. My own kids could never surpass anything I did back then...