Set up for the bench dip by placing two flat benches parallel to one another to around your legs’ length. Keeping your back straight and your arms outstretched, place your hands on the edge of one bench at about shoulder’s width and put your heels on the edge of the other bench, legs and buttocks swinging in the air (see picture).
While keeping your elbows tucked in, slowly flex them until they are at a 90° angle. Then slowly come back to the starting position and squeeze your triceps at the top. Keep your back straight throughout the movement. Repeat for desired reps.