When Craig goes up the stairs to fight Thor, Thor throws a set of weights down the stairs, hoping that they will hit Craig, and roll towards the doorway. But in the next shot, they are right next to the stairs.
When Franklin discovers the first burglar on a ladder inside the gym, he knocks over the ladder (with the burglar still on it ). The ladder and burglar crash through a wooden gate and hit the floor, you can see the burglar bounce twice. It is obvious there was a mattress to cushion the fall.