Lie supine (on your back) on a mat with your hips and knees flexed and your feet flat on the floor.
Place your hands behind your head.
Keeping your neck neutral and your feet flat on the floor, exhale as you sit up from the mat by flexing at the waist and hips.
Inhale as you slowly return to the starting position.
Repeat the sit-up for the prescribed number of repetitions.
Comments and tips
Perform the sit-up in a controlled manner. Do not thump your back on the floor when lowering your torso back to the starting position.
Do not pull on your neck. Keep it neutral throughout the exercise.
Performing the sit-up on a mat may help to prevent any bruising of your tailbone or lower back.
To keep your feet planted flat on the floor, you may tuck them under a bench or have someone hold them down.
Varying the position of your arms can make the sit-up either easier or harder. Your center of gravity is altered depending on where you place your arms. The farther your center of gravity is from the joint that serves as the axis of the movement (in this case, the hips), the harder it becomes. Thus, to make the sit-up easier, cross your arms over your chest instead of placing your hands behind your head. To make it more challenging, instead of placing your hands behind your head, stretch your arms overhead. To make the sit-up even more challenging, you may perform the sit-up holding a weight plate on your chest, behind your head or overhead.