Sit-ups are a powerful, dynamic exercise for your abdominals and hip flexors, but they often get a bad rap for causing back pain in some people. With correct form, sit-ups are a fun and safe exercise to add to your routine.
To do a sit-up, lie on your back and secure your feet. With your hands behind your head, raise your torso; then return to the starting position.
Proper Sit-Up Technique
Sit-ups use your abs to roll your body up off the ground and your hip flexors to complete the full movement. This is a great core exercise that can be done with little or no equipment.
Lie on your back on the floor or a bench. Bend your knees and hook your feet under a secure brace or overhang. If you don't have a brace to hook your feet under, ask a partner to hold your feet while you do sit-ups, advises ExRx.net.
Put your hands on the sides of or behind your neck.
Bend your hips and waist to raise your body off the ground or bench.
Lower your body back to the starting position.
Be sure to lower your upper back all the way to the ground after each rep. If you fail to do so, your abs only achieve isometric contractions, which is a tightening of the muscle without any movement.
To lessen the strain on your lower back, keep it pressed into the ground and your torso and spine in a C-shape. Some people tuck their neck when doing sit-ups, but if this is uncomfortable for you, keep your cervical spine in a neutral position by maintaining space between your sternum and your chin.
If you find it challenging to do a sit-up with your hands behind your neck, cross your arms in front of your chest and place your hands on your shoulders.
Weighted Sit-Up Variation
The weighted sit-up is a more challenging variation of the standard sit-up. To avoid injury, be sure to maintain proper form throughout the movement. If you cannot maintain correct form, decrease the weight or repetitions, or go back to an easier variation of the sit-up.
- Lie on your back with your knees bent and feet hooked under a brace or held by a partner.
- Hold a weight plate behind your neck.
- Bending your hips and waist, raise your body off the ground toward your knees.
- Lower your body back to the starting position, making sure the upper back returns completely to the ground.
Read more: What Are the Benefits of Weighted Sit-Ups?
This exercise can be made even more challenging by performing the sit-ups on an incline bench. This raises your feet above your head and increases the resistance as you perform the movement.
Alternatively, a decline bench can make the movement easier. Maintain the same form throughout the exercise.
Muscles Targeted During Sit-Ups
The primary muscles targeted during sit-ups are both the upper and lower rectus abdominis. These are the muscles in the front of your abs on both sides of your center-line. They flex the spine as you roll up.
Several other muscles work as synergists to assist the rectus abdominis during a sit-up, including the oblique muscles on the sides of your abs. Four muscles that help with hip flexion are also activated: iliopsoas, sartorius tensor, fasciae latae and rectus femoris. Because you start with your knees and hips bent, the brevis, pectineus and adductor longus hip flexor muscles are not used.
Finally, one muscle assists as a stabilizing muscle to steady the body during the exercise. That muscle is the tibialis anterior in the front of your lower leg. This muscle contracts, but does not move as you raise your torso during sit-ups.
Back Pain During Sit-Ups
Some people experience back pain while doing exercises like sit-ups or leg raises. This may be caused by muscle weakness.
When you do a sit-up, the psoas muscle pulls on the lumbar spine. The spine should be protected and stabilized by the abdominal muscles, but if these muscles aren't strong enough, the lumbar vertebrae become hyperextended, resulting injury or back pain, advises ExRx.net.
Other factors that may increase your chance of injury when doing sit-ups include an insufficient warm-up prior to exercise and using poor form. For example, jerking on your neck as your raise your body may place additional stress on your spine. If you are just starting an exercise routine, work your way up to sit-ups by strengthening your core before attempting the movement with the full range of motion.
Consult your doctor before beginning any exercise program. If you already have back pain, avoid sit-ups or any other painful exercise. If you experience pain during sit-ups, stop immediately and consult a medical professional.
Alternative Core Exercises
If you are still building up to a full sit-up or have back pain or an injury that prevents you from doing the full movement, you can still target your abs, hip flexors and core with alternative exercises, advises the University of Michigan.
For example, start with the curl-up. This is similar to a crunch, with a few differences. Instead of having both knees bent, only bend one knee and keep the other straight.
Use your hands to support your lower back instead of placing them behind your head. Then simply raise your head and shoulders up a few inches off the floor to do the curl-up.
Another alternative is the side bridge. Lie on your side with your elbow under your shoulder and your knees bent; then raise your hips until your torso is in a straight line. Lower back down to complete the rep. Do an equal number on each side.
The bird-dog exercise focuses on your back muscles. Begin on your hands and knees. Raise one arm and the opposite leg, and then repeat on the other side. As with all exercises, if this is painful, stop the exercise.
Correct form is critical to getting the most benefit from any exercise and avoiding injury. If you are unsure of your form or a good progression to build up to doing a full sit-up, consider consulting a personal trainer to help you develop a workout program.