Do you have a source for the exercise claims? That article pocket recommended me seemed to imply the contrary for walking. I don't mind walking my dog for a wh

Do you have a source for the exercise claims? That article pocket recommended me seemed to imply the contrary for walking. I don't mind walking my dog for a while or going on trails, but walking all the time for practical reasons doesn't register as fun for me. Additionally it seems like walking on concrete/asphalt strains my feet a lot faster than dirt/grass.