[Guitars+gems]

I doubt your hand hurts because of the strength required to form barre chords. More likely it's just that the muscles of your hand are aching because they're being used in a way they aren't accustomed to. That's why people here are wisely telling you that practice is the best way to become facile with barre chords, and build up the muscle memory in the process.

My son showed me that you can play a barre with your first finger without even using your thumb on the back of the neck. It's not preferable or even practical in actual use and when you add the other 3 fingers in, not using the thumb becomes pretty impossible. But I worked on laying my 1st finger across the strings, fret by fret (rolling that finger about 20% toward the nut, not on the flat of the finger) and making each string ring. And I was able to do it, which proved to me that barre chords are not about strength. You have to work on technique, as has been said, and for that there is a lot of help available in this forum.