It's on the first floor. This is not a question of strength at all, this is the foundation. I have been playing basketball for almost ten years, and some people seem weak. Take rebounding as an example: the correct way is to catch the ball with one hand and fall quickly with the other hand. The awareness needed at this time, the rebound in the frontcourt, whether to attack again or pass the ball, and the rebound in the backcourt, of course, to whom.