Walking fast, that is. Just meandering up and down the street isn't serious walking, but is a nice diversion from sitting around alone all day. Also, it's not pushing a shopping cart-that's just strolling down the aisle. Yes, walking is good, even with sore body parts from neuropathies or other injuries. And walking is free too.
Aerobic conditioning is healthful in a couple of other ways.
Second, endorphins are produced when you go aerobic for over 20 minutes. But save it for after those muscles are added on. You may be wondering just how to know when your muscles are plentiful enough to safely get into aerobic work. Visit a nutritionist or health center that measures body composition. The preferred measurement for this is a technique called Bio-impedence testing.