Well, perhaps not actual gymnastics. I must say that not having to do gym is one of the chief pleasures of being grown up as far as I'm concerned.
But each to his own.
Perhaps I might recommend a little mild waggling of the odd extremity, though. It's said to improve the circulation, and, if nothing else, it's great when you stop.
Gymnastics: I chose this word because its history is fun. The word gymnastics comes from the Greek word gumnazein, which means to exercise naked.
And that'd sell some tickets at the Olympics, wouldn't it.