I encourage my husband John with P's to go on he desk cycle in the morning as a routine. He has to be reminded every day! but I keep doing it. I leave it near his TV chair so that when he sits there, he can automatically do the cycling.
I find when he has been inactive, he is slow and not engaged. I also take him for walks cos I find he is much better in movement in outdoor spaces. He even likes throwing a ball at the park with grandkids but inside the house he moves slowly, mainly in the late afternoons.