Except for mild arthritic issues in my hands. my 76 YO body feels about as healthy as it did when I was 65YO and still bike commuting to work. I do ride less miles though after retiring because my riding was never about setting or achieving mileage/performance goals but rather to bike to and from places and destinations at my own pace and enjoy the ride, and that I feel makes me have less in common with the "concerns" and "attitude" of the performance/fitness oriented clique that dominates the posting on the 55+ list.