Walking
There were so few activities that were probably safe. Taking a stroll was one of them. With our worlds so small, it feels good to move around and luxuriate in the air that isn't stagnated inside your four walls.
Walks boost your physical health in obvious ways, especially during a year when we couldn't move about as much. But they also can apparently help improve your mental health, obviously important in a Hell Year. I am decidedly not a scientist and cannot fully explain why that is, but when I tell you walks have given me little serotonin treats, I mean it... More here.
I do a 2 mile walk before I start work (from home) every day and even though it means getting up earlier it makes a huge difference to me. I do the same at lunchtime and also have a quick walk after work, and take longer walks at the weekend. Rain or shine, windy or calm I simply have to walk because it is all I have in terms of any variety on a day to day basis at the moment.
It worries me that I know people who literally do not do any exercise each day and instead sit at home working for the entire day and then 'relax' in the evening. Even ignoring the fitness problems this will cause, the mental health issues will be exacerbated without any breaks during the day and it's a shame because almost everyone can walk no matter what their level of fitness (disabilities aside of course).