Lie on your back with legs bent 90 degrees at the knee (the standard "sit-up" position). Hold your hands lightly beside your neck. Curl your torso, using the abdominal muscles to pull the top of your chest up and toward your knees. Stop when your shoulder blades lift off the floor, pause there for a moment, then lower yourself in a controlled manner.


Arms crossed: Cross your arms over your chest, so each hand touches the opposite shoulder, then perform as above.