I am a 55 Y.O. youngster here and I have actually stepped up somewhat this year. 2000 through 2012 was a decrease of 16 major surgeries for me, 3 on my spine and 13 on the abdomen/ small intestine. Now that things have evened out for me health wise, save renal failure setting in, I am riding every day and my average speed has crept up to 16 mph from around 12 when I started back last year.
Adjusting my diet to save wear and tear on the kidneys has allowed me to feel like riding more and riding better. I have shed 34 lbs since April and will ride a metric century shortly. The mental part has been helped here at the 50+ forum, the senior (in years, respectfully) members like Denver Fox, Zonatandem and others that have kept their health at a higher level inspired me to keep riding and our members like Blues Dawg, Beverly and others have shown me you can even beat cancer and use riding to keep you sane. This aspect is much larger than you can imagine, having others riding and conquering things you thought impossible just 2 years ago can help you to realize your goals and go beyond them, too.
Scaling back is a necessary part of our aging and I try and use common sense to govern my exercise and my diet, not go to extremes I could not sustain. I let riding be a joy for me, not a training burden as if I was racing like the mid-late 70's again.
Oh, And I do ride clipless now and this years N+1 didn't hurt my positive mental state either.
Bill