Ok at first i had serious trouble throwing a left hook but now i can throw one but it just feels weak. And when i do a left hook on my heavy bag i feel like im gonna tear my shoulder. My straight left is good(im a right handed southpaw) and my uppercuts are good. My left hook to the body is ok but its not what i call powerful. All i know is i dont know whats wrong with it. Some1 help. I mean im throwin it good. I dont knot im leavin it up to you guys.