I also caught the bug in the 70s. Everyone in my highschool was riding the ten-speeds. I had a Peugeot PR10 with sew-ups, and then a Legnano bike with Reynolds 531 and all Campy SR stuff.
30 years later, I weighed 475 pounds and walked with a cane.
As I got my life back together, I started by walking, and then eventually jogging a bit. I was on the MUPs so I had plenty of roadies riding past me. It really gave me a goal to go for, and as soon as I lost enough weight to be able to do so, I got back on the bike, first with a hybrid, then a road bike with a triple, and finally with a series of over-expensive indulgence bikes.
Lost about 300 pounds overall, and if it weren't for biking, I'm sure I'd be heading right back there. So I keep riding.