Hi Teresa, For me the change was gradual. I still enjoyed golfing, biking and racquetball with a few friends into my mid 50s but I started slowing down into my 60s when it was harder for me to walk any distance. Then when I got into my 70s and the walking became more difficult, I found that it was easier to spend time doing exercise in my home on a recumbent bike/elliptical combination machine which I eventually exchanged for a Teeter FreeStep Cross Trainer. It's easier on the legs with a more natural walking motion and it also exercises the arms.