Do whatever combination of activity suits you. I'm not terribly interested in what politicians think I should or shouldn't do. I often take two forms of exercise daily. For example on Friday I was on my feet at work all day, plus I rode 12 miles as well. On Saturday I rode 8 miles and walked a couple of miles. Yesterday I rode 18 miles but didn't do any walking. Today I've ridden 5 miles early this morning, plus walked 3 miles doing shopping. I'll also be going out for another ride of about 10 miles this evening if the weather stays OK. Often when I do a morning and evening ride on the same day, I spot the same dog walkers, so they are also going out at least twice, and possibly other times too when I'm not out so therefore don't see them.