Reinhold, Like Jim, I am in my 60's.
I have owned my 12x20 Korona for about 18 years now.
For the past 3 years I have used a jogging stroller to push the camera around.
Some pros to the jogging stroller are, it's easy to fold up, and on mine, the wheels slide off for easy packing and it is light weight.
The con is one needs to be careful about the center of gravity of the stroller, it will fall over backwards if I don't have the load centered. Also, in some rare cases I have been told I cannot take the stroller off road in a national park. An example of this is at Mono Lake, a ranger told me I could use the stroller on the wooden pathway leading down to the shoreline but I was not allowed to use the stroller off the pathway, so I carried the camera to the location I wanted. I won't do that again.
if you can, try to borrow or rent different trollies and try them out to see what works best for you.