Looks like many of us have back , leg and foot problems and I thought I join in by listing what I have tried .
The biggest thing I found that helped is some good foot wear and cushion insoles and the best thing I ever did was putting in floor hot water heating in .

When I built my new work bench I designed a removable seat that has proven to be very handy to serve as a resting place .
A piece of carpet underlay in front of the bench also added some comfort but I am still undecided if I should expand on that solution as I am always worried about tripping .