Get on your hands and knees, with your hands positioned wider than shoulder width apart.
Extend your feet backward, and straighten your body so that you are supporting your bodyweight on your hands and toes.
Execution
Keeping your body straight and rigid, lower your chest as far toward one side as possible.
Keeping your chest close to the floor, shift your body as far as you can to the opposite side.
Keep alternating the side to which you shift your body while keeping your chest close to the floor.
Breathe naturally.
Comments and tips
The isometric wiper is not a mass-building exercise. Use it either to warm up your chest at the start of a chest workout or to burn it out at the end of a chest workout.
Your pectoralis major and anterior deltoid are mainly exercised isometrically, whereas your triceps brachii is exercised dynamically.
Your elbow flexors (biceps brachii, brachialis, and brachioradialis) get involved to a significant degree only if you position your hands out very wide, like in the video.
If you perform the isometric wiper with a very wide hand position, point your fingers out to the sides to reduce the pressure on your wrists.
