How to Do the Hollow Body Crunch Properly

The hollow body crunch is a great exercise to build your core muscles.

This exercise is very popular with gymnasts. It is highly effective for crushing your abs.

The hollow body crunch relies on bracing your abs and creating a full-body tension. It is a highly effective exercise that enables you to transfer energy from your upper body to your lower body without wasting it.

To do this exercise:

  • Lie down on the floor with your legs extended and your arms at your side.
  • Engage your core and drive your lower back into the ground. Squeeze your inner thighs together to help complete the move. Ensure there is no gap between your lower back and the floor.
  • Raise your legs about two inches off the floor.
  • Raise your head about two inches off the floor and extend your arms overhead and behind you. Ensure your back keeps pressed to the floor.
  • Hold for at least 30 seconds or longer (if you can) before lowering your legs to the floor.


The hollow body crunch primarily targets the core. It also works on the quads, hip flexors, inner thighs and erector spinae.


These are the deepest muscles found in the abdominal region.

The muscles wrap around the abdomen. They help you tense the abdominal wall stabilize your pelvis and lumbar spine.

They also help secure the internal organs in the abdomen.

This is one of the main muscles that help brace your core.

2.      OBLIQUES

These are the muscles found on the sides of your abs. The obliques are made of two muscles, the internal obliques and external obliques.

The internal obliques support the rotation and bending of the torso. This is when the hollow body crunch engages them.

They help with heavy breathing and maintaining tension in the abdominal wall. They help with bodily functions like urination, pooping and forced breathing.

Weak internal obliques can increase the risk of internal hernias.

The external obliques start at the lower ribs and extend to the pelvis. They are located above the internal obliques.

They help with twisting the torso, rotating the spine and bending the chest forward.

The obliques work together to bend the body sideways.


This is the part of the abs that form the famed six-pack. It is located at the front of the abdominal wall.

It starts at the rib cage and extends down to the pubic bone.

Its main function is flexion of the trunk, stabilizing and controlling the tilt of your pelvis.


As mentioned earlier, the hollow body crunch also works on the quads, hip flexors, inner thighs and erector spinae.

The quads (quadriceps) are four large muscles that are found on the front side of the thighs.

They help with flexion of the hip joint and extension of the knee, tracking the knee and limiting the flexing of the knee.

These muscles work together to extend the knee.

Hip flexors are a group of muscles found at the top of the thighs.

They help move your thighs towards your torso. They are the primary connector between the torso and the legs.

Hip flexors help with flexing the hip joint, externally rotating the hip joint, hip adduction and strengthening the core.

The erector spinae is a group of muscles that connects your entire back from your hips to the base of your skull. These muscles are found on either side of your spine.

They help with lateral flexion and extension of your trunk and side to side rotation.



The hollow body crunch trains your core to resist arching your lower back.

This increases the stability of your mid-section and helps you maintain a neutral spine when doing your day-to-day activities.

This also helps reduce the risk of lower back pain.


This exercise helps boost your core strength.

This results in stronger abs. Movements that you perform daily such as vacuuming, mopping, picking things off the ground, pushing trolleys, bending, standing, sitting, jumping rely on a strong core.

Having functionally strong abs makes it easy to do these activities without worry of injury.

When your core is stronger, your stability is higher. Your body constantly readjusts to prevent falling or swaying when simply walking or doing dynamic activities.

Strengthening your core also makes it easier to take deep breaths. Strong abs help keep your internal organs properly positioned which makes breathing easier.


Having strong abs helps you bend, twist and rotate at your core with ease.

If you play sports that involve swinging motions such as swimming, tennis or golf, having a stronger core helps you perform more efficiently.

You also minimize the risk of injury.



To do this exercise:

  • Lie on your side perpendicular to the bench.
  • Raise your legs and place your lower ankle on the bench.
  • Brace your weight with your arm. Keep your elbow and forearm under your shoulder with your hand pointing away from you.
  • Keep your body in a straight position and hold as long as desired.


To do this exercise:

  • Lie on your back in front of a bench.
  • Reach behind your head and grab the bench with your hands then raise your legs half a foot off the ground.
  • Contract your hip flexors and core to lift your legs until they face the ceiling.
  • Lower to the starting position and repeat for the desired reps.


Avoid lifting your back off the floor. When this happens, it means you have not engaged your core. If you keep losing the connection to the ground, try switching your arm or leg positions.

Try holding your arms to the side or bending your knees.

Avoid letting your shoulders touch the floor. If you aren’t contracting your core enough you won’t be able to raise your shoulders. You need your shoulders slightly raised to create tension in your core.

Avoid tucking your chin when doing this exercise. This increases the risk of neck strain. It takes your neck out of neutral alignment.

Additionally, it reduces tension in your core.