I am 62 years old and still riding strong. One of our winter riding partners is 74 and still going strong…he can go forever, if a bit slower on the single track. Started riding in Marin County in the very early 80s and never stopped. I don’t really feel like I have slowed down…and of course the equipment has improved so much…it is still a blast to get out and rip single track. I currently ride a Specialized Comp 29 which works perfectly in Southern Arizona, where I live, and Sedona, where I used to live and still visit frequently for the great trails. BTW the Sedona Real is a very bike friendly hotel in Sedona…decent rates, BIG rooms (you can take your bikes in the rooms), nice pool for the post ride cool down. The trail system in Sedona is really excellent…during the very warm summer the Aerie Trail is the perfect hour long sunset ride…plenty of time to do it from the Boynton Canyon Trailhead after the sun has disappeared behind Bear Mountain.