My spousal unit and I are both in our upper fifties, me = 58, spouse = 57. We got into this about three months ago to get out of the house and get some exercise. We cache with our daughter and 4 year old granddaughter.
So far we have limited our hiking to caches of 1/2 mile or less since the granddaughter gets tired on those over a mile long. She just loves to find treasure and it warms us to our innards when she does. Me with a bad ankle, knee and hip from "jumping outta airplanes" while in the 82d Airborne Division, and spousal unit with two bad knees, the hikes have been limited so far. As we get better at this, the hikes will increase in difficulty and length.
For those of you familiar with the summer temps in AZ, you can understand why we will do most of our hiking in the spring and fall seasons. Yea, I know, it's a dry heat.
We both carry collapseable walking sticks, not so much for the terrain, but to get a head start on the rattlesnakes we have here.