I'm not only new to the Forum, I'm fairly new to cycling.
A few basic facts: I'm male, 69 years old, moderately athletic (I did a martial art for many years, until I had to have a knee replaced), a cancer survivor, a retired woodworker, a model railroader, and a hospital volunteer.
A friend (Tara) started taking spinning classes and got a lot from them, so I started taking them, and pretty quickly got up to four classes a week. She and her husband (my shop partner) bought new bikes and he (Garth) gave me his old mountain bike. (It's a Diamondback.) I pretty quickly found a new obsession to replace aikido.
We're fortunate to have a great network of rail trails in this area and I've been doing longer and longer rides. My longest so far is 30 miles and I'll be trying 35 later this week.
Tara talked me into signing up for That Dam Ride this September - it's 70 miles from Boston, PA to Confluence (specifically, to the dam at Confluence) and 70 miles back the next day. It's kind of a scary idea but if I train vigorously all summer, it should be do-able.
Bike riding seems to good for my titanium knee. I worried about that some.