No, not necessarily. Most of those jobs require training and to start as an apprentice. Girls might have a more difficult time to be accepted as apprentices.

And since those jobs are specialized (take plumbing), unless someone teaches you and gives you your first job at the field, it is difficult to join.

It can be difficult for boys too, by the way. People don't want apprentices to fix their plumbs, they want someone who already know what to do. So usually those jobs are family jobs.

But a plumbing job is not more "back breaking" than being a nurse that might need to lift a grown man to help him clean himself at a hospital. And nurses get dirty (think cleaning feces). Comparable burden, danger, effort, etc. Yet, nurses make less money than plumbers.