All of the above.....
A couple years ago Docs were all over my ass. My wife was riding, and she went for a ride, and I was going to just follow her for a mile. I should explain something. I live on the side of a mountain, it's a dinky mountain, a hiker (which I used to be) would call it a hill. But that is where I am. SO when I say I went around the block, it's a triangle, I go across, up, and down the back side. We went across, and the wife went on up the hill. I watched her go, and felt the urge to keep going. I figured it would prob kill me, but
I got a what the hell feeling. I can go around the block in 40-45 minutes now. It took me over an hour and a half, but I made it. I also redefined for myself what the bod was capable of. That was in the fall. Spent the winter in the gym, building a base. Come spring we started doing trips, short ones, each a little longer than the last. In August the peak came on a 5 day bike trip to another state. It was the 2nd day, and we had come to the top of a mountain, and were in a col (a col is a valley on a mountaintop,usually just a little thing between peaks). There was an echo, and I started yelling "WHO LET THE DOGS OUT WOOF WOOF"
I hadn't felt that good in a million years. So I ride to lose weight, I like it a lot, it gets me back into the mountains I love,all those reasons and more. But the real reason is...it gave me my life back.