When I was a kid, I loved to hula hoop. I used to be pretty good at it. As I've gotten older and, to a degree, weaker, I've lost my rhythm. I have been working on getting that back. Sometimes I can get the hoop going pretty good. Other times it is like gravity wants the hula hoop more than I do and it wins, banging the hoop to the floor.
We have three hula hoops. One is yellow because it is our youngest son's favorite color. One is purple because it is our youngest daughter's favorite color. The purple one lights up. The other is a dark pink color for our oldest daughter. The yellow one works the best for me. According to the kids, it has water in it to help it maintain balance. Whatever it is, I can do pretty good with that one. I like to try to spin around while the hoop is spinning. I've successfully turned completely around ONCE before the hoop took that trip to the ground. I'll get there.
It isn't major exercise, but it is what I can do right now while I work to get my strength back. Who knows, maybe while it's getting my waistline back, it will also help me to recover my brain. :)