Mastering the pull-up is difficult but necessary

A pull-up is a classic strength exercise that challenges your upper body, including your back, shoulders and arms. — Photos: dpa

Achieving a pull-up is a significant fitness milestone for many people.

First one, then maybe five, 10 or more: “The ability to do pull-ups is, in my book, an impressive sign of fitness and not a given,” says physiotherapist and trainer Johannes Frank, proprietor of a fitness facility in Berlin, Germany.