I recently took up learning to play squash. One of the hardest things to learn about playing squash is the behaviour of the ball itself. There are different types of squash balls intended for players of various experience levels. The difference lies in the amount of rubber and air inside each type of ball.

Depending on the kind of ball you are using, you’ll find out that when you first start playing, it takes great effort to hit the ball against the wall and have it bounce back to where you want it to.

I quickly found out eventually, that an important part of playing squash is to first ‘warm up the ball’. This is done when players hit the ball hard against the wall in such a way as to make it possible for the other player to do same. After about 6 to 8 of such hits or volleys as they...