There is a funny „writing exercise“ that kids like to do and it makes them very proud, when they just learned how to write. It’s also a very good exercise for the abdominals of adults.
Just sit down on a mat and support the torso with your elbows. Then lift your straight legs and start to write your name. It’s important to keep the back absolutely straight!
The effectiveness of this exercise depends of course of the length of your name. If someone’s name is Pia, Joe or Lara, maybe it’s better to write also the surname.
Lots of fun for the writing.