The brace works by pulling your shoulder backwards so you, naturally, make yourself straight. That is it. If you were going to wear a heavy backpack, you will do the same, but with the brace, you are not carrying a heavy weight all the time, so you don't lean forward, you actually stand straight. Now, after a while wearing the brace, you get use to it. I wear it while working on my computer and I notice a different in the way I sit. Also, I wear it while exercising (HIIT sessions), and it didn't...