How to Do the Hollow Body Hold for a Stronger, More Stable Core

Whether you have big goals of rocking pull-ups or hanging leg raises, the hollow body hold is one of the best core exercises to have in your ab arsenal. As one of the hardest ab exercises, this deceptively difficult move torches your core through an isometric hold (no movement). The good news is that it can be modified for all fitness levels, making it a great option for those who want to really hammer their core.

• ‌What is the hollow body hold?‌ It's an isometric core exercise that's done lying on your back and lifting your legs, arms and shoulders off the ground for a period of time.
• ‌What muscles does the hollow body hold work?‌ Your core gets most of the action, especially your transverse abdominis — the deep abdominal muscles that stabilize your back. But it also strengthens your hip flexors, quads and lower back.
• ‌Who can do the exercise?‌ It's best for intermediate and advanced exercisers because it requires being able to sustain intense core contraction by lifting your legs, arms, and shoulders off the ground for a period of time. Beginners can hold their legs higher or start by bending their knees and holding their shins parallel to the floor in a tabletop position (see below), says Sarah Louise Rector, CPT, a certified personal trainer and founder of the SLR Life, an online fitness program.
• ‌How long should you hold the hollow body hold?​‌ Start with 30-second intervals and work your way up as you get more comfortable with the exercise and build strength.
  

It fortifies your transverse abdominis — the deep stabilizing core muscle — which helps protect your back and hips from injury. When you press your lower back into the floor, your obliques are also enlisted to maintain a strong, stable hollow hold, Rector says.

Core stability is not only important for athletes, such as runners, swimmers and weightlifters, who rely heavily on their trunks to power their performance; it's also key to carrying out everyday tasks with strength. Every time you push a door open or lift something heavy off the top shelf, you are using your core to stabilize your body.

And because the hollow body hold keeps your core muscles under tension for an extended period of time, you'll also improve your muscular endurance while boosting your strength.

Although it's not a hip-focused exercise, this move strengthens your hip flexors, a group of muscles that runs across the front of your pelvis, according to Carolina Araujo, CPT, a California-based certified personal trainer and founder of Fit With Carolina. When you do a hollow hold, your hip flexors work to keep your legs elevated and stable in mid-air.

For most people, these muscles are a problem area because spending a lot of time sitting causes them to tighten and weaken over time, she says.

Stronger core muscles and hip flexors mean better posture, too, according to Araujo. By strengthening these muscle groups, hollow body holds build stability in your back and pelvis so you can stand (or sit) up tall. In the long run, this can also help minimize back pain and hip tightness.

It's important to keep your spine 'imprinted' on the ground with no gap between your back and the floor, according to Rector. If your back floats off the ground, you miss out on the core-building benefits of the exercise and put your lumbar (lower) spine at risk for injury.

Hold your legs in a higher position or bend your knees to 90 degrees if you struggle to keep your back flat against the ground. To ensure your back is in the right position, try slipping your hand under your middle spine. Ideally, there shouldn't be any space between your body and the floor.

If your butt sticks out during this exercise, it's harder to engage your deep core muscles. Plus, you risk raising your lower back off the ground.

"The slight tuck of the pelvis provides deeper engagement in your core region and is a great mindful workout technique when performing an exercise that uses your abdominal muscles," Rector says.

Before you raise your legs, think about tucking your pelvis to create a straight line along your entire spine down to your butt. You can glance at a mirror to check that your hips are tucked properly.

Shallow breathing or holding your breath can make it difficult for you to brace your core properly and sustain the tension in your abs. Instead, release your breath as you squeeze your muscles to bring your body into the hollow hold position.

From here, take deep, steady breaths throughout the duration of this isometric hold. Remember, your muscles require a consistent flow of oxygen to work at their best.

To avoid muscle imbalances or unwanted strain on your upper spine, keep your neck in a neutral position as an extension of the spine. There should be no backward tilt (chin pointing up) or forward tilt (chin tucked in) of your head to reduce unwanted compression or stress on your neck and spine.

Squeeze your lower-body muscles, including your quads and inner thighs, throughout the exercise. Think about lengthening from your hips all the way through your toes to maintain the hold and keep your body stable on the ground.