A man demonstrates how to perform ab mat sit ups.
A man is demonstrating proper sit up technique using a mat.
A guy is lying on a gym demonstrating an abmat sit up.
A man is doing sit ups with a foam wedge behind his back.
A man in a gym is doing exercises by doing sit ups.
a man doing straight leg sit ups with some sort of sit up pad under his back
A man is lying on the floor doing sit ups with a prop under his back.
A man is laying on the floor in a gym and doing sit ups very slowly
A man is laying down and he is doing sit ups while laying on a black mat.
A man performs a series of stomach exercises while laying down and lifting his upper torso up.