“Core” has been a buzzword in the yoga and fitness world for years. Everyone thinks they understand its meaning, but the term is seriously misunderstood.

The most common misconception is that a strong core means you’re always holding your stomach in.

Core is far more than just abdominals and doesn’t have anything to do with holding your stomach taut.

Instead, picture yourself wearing a half-wetsuit that covers your entire torso—from your hips, around your midriff and all the way up to your shoulders. This is how big and expansive the core is.

Two layers of core support

When we delve deeper, there are also two layers to the core. These are often referred to as the inner cylinder of support (deep core) and the outer cylinder of support (superficial core). The inner cylinder comprises four muscles that work together to produce intersegmental support (support from one vertebra to the next). These four muscles are the transverse abdominis, the pelvic floor (specifically the levator ani), the diaphragm and the multifidi. The outer cylinder of support wraps around the torso toward the upper body from the hips and pelvis. The outer cylinder includes the gluteals, latissimus dorsi, back extensors and abdominal obliques, to name a few.

How the inner and outer cylinders work together

The key to understanding the importance of these two cylinders of support lies in how they work together.

Many of us are unaware that the outer cylinder of support depends on the inner cylinder. The muscles of the inner cylinder act like a vacuum pack that keeps the spine secure. This stability provides a base of support for the muscles of the outer cylinder whose job is to move our bodies around in space. The inner and outer core muscles are designed to work in unison!

Most of the time, when it comes to core, we focus on working the muscles we can see: the ones that have sex appeal (the visible “six-pack”). The irony is that these muscles, while important, are not part of our core. They need to be strong to move us around but they perform no function when it comes to direct support for the spine. Also, the muscles of the inner cylinder are accessed in subtle ways that require patience and practice. In fact, when you start training the inner cylinder, it often feels like you are doing nothing and confusion sets in because we’re so use to paying attention to and “feeling” the bigger muscles. Understandably, these muscles are easily overlooked. These two factors contribute to a misunderstanding of what “core” means and can lead, in some cases, to core weakness because the wrong muscles are being targeted.

To create truly integrated support around our spine, we need to understand the interplay between the two cylinders to be able to toggle back and forth between the two. When we have a double cylinder of support our bodies are lithe and can move freely and powerfully. Unfortunately, what often happens when we’re trying to strengthen our core is that we get rigid. Rigidity can cause issues in our back, hips and even our necks. This leads to poor posture and restricted breathing because the inner cylinder can’t do its job proficiently.

True core strength and control translates to resiliency, elasticity and tone. It also allows for good movement in the hips and shoulders, free breathing and a full range of pain-free motion through the spine.

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Here are six exercises (three for the inner cylinder and three for the outer cylinder) to build integrated core support—to increase mobility, strength and balance while reducing chances of injury or chronic pain:

Inner cylinder exercises

This exercise targets lumbar multifidi muscles, deep along the spine. These are essential inner cylinder muscles that provide significant support for the lumbar spine. You won’t feel the multifidi during this exercise, but afterward, you may feel like there is more space and mobility in your lower back.

Split stance rocking

  • Stand with left foot forward and right foot back
  • Rock forward onto left foot and then back onto right foot

Do 20 reps, then switch to other side for another 20 reps.

Belly to spine activation

  • Stand with hands around waist
  • Take a breath and expand torso in all directions
  • As you exhale, cinch waist in
  • Take another breath and expand
  • Exhale and cinch

Do 10 to 15 reps and make sure the contraction in the abdominal wall is minimal.

This exercise targets the diaphragm and transversus abdominis (the deepest abdominal muscle). These are two deep inner cylinder muscles.

Lower belly to spine pulsing activation

  • Stand with one hand against lower belly
  • Start to take small, staccato breaths
  • On each exhale press lower belly toward spine

Do 10 to 15 reps and make sure the contraction you create in the abdominal wall is minimal.

This exercise targets the diaphragm and transversus abdominis (the deepest abdominal muscle). These are two deep inner cylinder muscles.

Outer Cylinder Exercises

Hip hinge

  • Stand with hands on hip creases
  • Hinge forward from hips approximately 30-40º, then reverse to tall standing

Do 6 to 10 reps.

This exercise targets the gluteus maximus muscles bilaterally (on both sides). These muscles are an important component of the outer cylinder.

Quadruped arm/leg reach

  • Start on hands and knees with a slight downward dip in lower back
  • Press lower belly to spine (for deep, inner cylinder activation) and press down with left arm and right leg. This activates the abdominal obliques (outer cylinder muscles)
  • Next, reach right arm and left leg long to the height of the torso
  • Reverse to the start position

You can alternate from side to side or do a number of repetitions with one set of limbs and then switch. In either case, do 6 to 10 reps, keeping torso steady and supported.

This exercise targets what is sometimes referred to as the back track of the body, targeting hamstrings, gluteus maximus and back extensors.

Side bridge

  • Lie on side, propped up tall on your right arm
  • Position knees slightly forward of hips, bent at 90º
  • Stay tall on supporting arm and press legs into floor
  • Lift waist and hips to create a long diagonal from shoulders to knees
  • Lower down to start position

Do 6 reps and repeat on other side.

This exercise targets the side of the torso from armpit to hip and includes outer cylinder muscles for lateral support.

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