Inner Core Muscle Training 

By Robin Angus PT, MS, Cert. MDT

 

The transversus abdominis, pelvic floor, deep lumbar multifidi, and diaphragm muscles form our inner core muscles as discussed in my April 2016 blog post. Research shows that the transversus abdominis, pelvic floor, and deep lumbar multifidi muscles co-contract to stabilize our spine before movement of the legs and arms occur. However, their activation is often delayed or absent. In addition, they can have too little or too much activation and they often fail to work together correctly.

If these aberrant muscle co-contraction patterns aren’t corrected, they may lead to degeneration of the underlying joints due to loss of stability and control of motion. The patterns generally won’t change on their own; patients therefore often require the guidance of a physical therapist to restore normal inner core muscle function and performance.

Pain, fear of pain, trauma, surgery, childbirth, and poor awareness of our muscles “down there” are some causes that disrupt our ability to optimally contract these muscles at the appropriate time or with the proper amount of force (“amplitude”) needed for movement. This is known as “motor control” and involves the connection between our brain and muscles. If muscles aren’t receiving the correct messages from our brain, then their activation patterns and ability to strengthen will most likely be compromised.

If we’re unable to properly strengthen inner core muscles that demonstrate poor motor control, then what is one to do? Rehabilitate them! Diane Lee and Linda Joy (LJ) Lee, prominent Canadian physiotherapists and international educators on lumbopelvic-hip dysfunction and inner core muscle performance, advocate a three-step process in restoring optimal recruitment and timing of these muscles. Step one involves training muscles to contract in isolation, often through the use of imagery, since a muscle that is inhibited or not optimally activated can’t be properly strengthened. Being able to isolate each of the inner core muscles allows us to be able to co-activate that muscle along with the other inner core muscles at rest and with breathing, which is the goal of step two. Diane and LJ’s final step is to learn to contract the inner core muscles together at the right time and with the appropriate amplitude so that they can provide stability of the lumbopelvic and hip regions with progressive strengthening exercises and functional activities (1, 2, 3).

The Pelvic Floor Muscles

The pelvic floor is comprised of several layers of multiple muscles. It is not uncommon for some muscles to have minimal to no activation while others may demonstrate excessive activation patterns. They may also activate at the wrong time. It is therefore necessary to train optimal recruitment patterns before strengthening activities can be commenced.

Diane and LJ’s training program uses a number of verbal and visual cues to help our brains connect to and activate the inner core muscles. Their program for pelvic floor muscle training begins with you on your back, in sidelying, and/or sitting in neutral alignment. Palpate your lower abdomen 1-2 inches inside of your hip bones with your finger tips while using these cues to help correctly contract your pelvic floor muscles (1,2, 3):

* Females – “Think of your vagina as a clock, pubis is 12, tailbone is 6, left lateral wall is 3, and right lateral wall is 9. Visualize drawing the 12 to the 6, the 6 to the 12, and finally gather the 3 and 9 toward the middle of the clock and gently lift.”

* Females – “Connect a string between your pubic bone and your tailbone, then between your right and left sitz bones. Now draw the string up into the center like a drawstring.”

* Females – “Visualize gently squeezing/closing off the urethra as if to stop urine flow, hold this while you gently squeeze/close the anus as if to stop flatulence and then gently lift, as if you are lifting a tampon.”

* Males – “Visualize gently drawing your testicles up and forward into your abdomen. (aka ‘bring the boys home’).”

* Males – “Imagine that you are slowly walking into cold water that is starting to come up between your thighs.”

As with training of all the inner core muscles, exhale with exertion and inhale while resting or holding a muscle contraction. While inhaling, bring air into your lower abdomen and also into the lower ribs. You may need to imagine the lower rib cage opening like an umbrella with inhaled air moving into all areas of the lower rib cage, especially the sides and back. On the exhalation, contract your pelvic floor using one of the above cues.

When performed correctly, gentle tension is felt in the lower abdomen. Common compensations when trying to isolate the contraction of the pelvic floor muscles include:

* Buttock and/or leg muscle tightening.

* Posterior pelvic tilting.

* Rib cage depression (rounds toward your back).

* Fingertips being pushed out by inappropriately activating the internal oblique.

* Holding your breath. Remember to exhale with your exertion and to inhale when holding a contraction or resting.

* Activating your neck muscles.

The Transversus Abdominis

The deepest muscle in the front part of the abdomen is known as the transversus abdominis, a muscle that wraps around the abdomen horizontally. Diane and LJ use the following cues to activate and isolate the transversus abdominis (1,2):

* “On your back, imagine a line connecting the inside of your two pelvic bones. Connect to the muscle along this line, bringing these two points together as if the muscle were closing a book’s front and back cover together.”

* “Imagine a guy wire that connects the inside of your hip bones. Slowly and gently draw the hip bones together through this line.”

* “Imagine there is a slow tension coming up from the inner thighs into the front of your pelvic floor, then extend the tension into your lower abdomen.”

* “Contract your pelvic floor by drawing the muscles from behind your pubic bone to your tail bone and the left and right sides of your pelvic floor from the left and right sitz bones together. Like a drawstring bag, gently draw the entire pelvic floor up.”

* “Imagine drawing your stomach away from your pubic bone. Very lightly and slowly think of lifting up your pelvic floor.”

* “Imagine a sling or hammock that runs from the pubic bone to the right and left hip bones (ASISs). Now, slowly and gently create tension in the sling to lift up your lower stomach.”

* “In sidelying – gently lift your lower belly up away from your pubic bone.”

While performing these activities, place your hands just inside your two hip bones. If you feel your fingers being pushed out, you are contracting the muscle too much. You should feel just a light tightening under your finger tips. There should not be any movement of your spine, pelvis, or hips while you recruit the Transversus abdominis. Remember to breathe as noted above, activating the transversus abdominis on the exhalation.

Initially, it is common for other muscles to inappropriately co-contract when trying to isolate the transversus abdominis. Be aware of the following compensations:

* Bulging of the abdomen.

* Buttocks tightening.

* Posterior pelvic tilting.

* Rib cage depression (rounding your upper back).

* Fingertips being pushed out by inappropriately activating the internal oblique.

* Holding your breath. Remember to exhale with your exertion and to inhale when holding a contraction or resting.

* Activating your neck muscles.

The Deep Lumbar Multifidi

The deep lumbar multifidi muscles connect one vertebra to another in the spine and play a vital role with the other inner core muscles maintaining stability in the pelvis and low back. In either a neutral position in sidelying or on your back, Diane and LJ recommend the following cues to help you connect to the muscles and contract them in isolation from the long vertical muscles in our back (1,2):

* For the part of multifidus that supports the SI joint – “imagine a line that connects your left and right SI joints/bones on the back of your pelvis and think about connecting, or drawing these 2 joints/bones together along this line.”

* “Imagine a line connecting your groin, back of your pubic bone, or inner thigh to the part of multifidus in your low back you are trying to train. Connect along this line and then gently think about suspending (lifting) the vertebra up towards your head.”

* Since the deep fibers of the multifidus work together with the transversus abdominis and pelvic floor, try cues for these two muscles to help co-contract the multifidus.

This is a difficult muscle for some people to activate. Common compensations while trying to contract the multifidi include:

* Holding your breath. Breathe into your abdomen and lower ribs and on the exhalation, try to connect to the multifidi muscles.

* Moving your spine, hips, or legs.

* Engaging your neck muscles.

* Moving your spine, hips, or legs.

* Tilting or rotating your pelvic bones.

* Arching your back.

* Tightening your buttock or hamstring muscles.

Like other muscles in our body, training the inner core muscles to contract in isolation is hard work. Once you learn to do this correctly for each of the muscles, the next step of Diane and LJ’s training program is to focus on co-activating these muscles at the appropriate time with the correct amplitude in multiple positions (1,2). When this is accomplished, progressive load strengthening exercises and functional activities for the core muscle group are introduced. I will write about these last two steps in a future blog article. If you have questions in the meantime, speak with your physical therapist. For more information on inner core training, I highly recommend reading some of Diane’s articles on her website (3).

1. Lee, Diane, Linda-Joy Lee, and Andry Vleeming. The Pelvic Girdle: An Integration of Clinical Expertise and Research. Edinburgh: Elsevier/Churchill Livingstone, 2011.

2. “Training for the Deep Muscles of the Core.” – Diane Lee and Associates. Web. 23 May 2016.

3. “Articles For Clients.” – Diane Lee and Associates. Web. 23 May 2016.