the sexual position where the girl has her ass in the air, face down, and the guy is standing over her with his legs in front of her banging her with a downward stroke using a frog-like squatting motion. This may involve having to hold your penis directly downward, which may be painful depending on how well endowed you are. Very common position in low budget porn.
His well defined legs were not a product of the gym. They were from the frequent frog stomping that he gave his old lady.