Lift your head, upper body, and legs off the ground simultaneously, using your back muscles, while keeping your arms straight and parallel to the floor.
As you lift your upper body, swing your arms down to your sides and then behind you, keeping them straight.
Then, lower your upper body and legs back to the ground while swinging your arms back to the front, returning to the starting position.
Repeat this movement, keeping it fluid like a diving motion, for the desired number of repetitions.