Low Back Pain – Part 3 – BEST Evidence-Based Core Exercises!

So what are the BEST evidence-based Core exercises?  

Evidence from random controlled trials of people suffering from low back pain show that core stabilization exercises result in significant improvements in pain and function(5,7) . However, the most effective combination of which muscles to target and which stabilization methods to utilize are still debated(1-11).  One technique that has been suggested is abdominal hallowing or “drawing-in” your navel to activate the transversus abdominis (TrA) muscle.  This technique has been shown to increase the cross-sectional area of the TrA(10), however, many exercise scientists are now advocating a method called “abdominal bracing”(demonstrated in my last post) in which ALL the abdominal muscles are recruited instead of just one(11). It should be the goal of core exercises to activate as many torso muscles as possible in order to ensure spinal stability and to prepare our bodies for the dynamic and often complex movements that occur during our daily activities.  So what does the research say about which exercises activate which muscles the best?

Numerous studies have used EMG to determine the greatest electrical activity of torso muscles during various core stabilization exercises.  In Escamilla et al(3), they used surface or skin electrodes to compare exercises such as traditional crunches, sit-ups, reverse crunches, and hanging knee-ups using straps to exercises using an Ab Roller/ Power Wheel and a device called the Ab Revolutionizer. What they found was that the activation of the upper and lower rectus abdominis(the “washboard” muscle) as well as both the internal and external obliques was the greatest with Power Wheel roll-outs and hanging knee-ups with straps.  Because research indicates that the internal obliques are activated in the same manner(within 15%)  as the tranversus abdominis(3), we can assume that these results apply to the TrA as well. The activation was least with a traditional sit-up!   In Okubo et al(8), they used both surface electrodes and intramuscular fine-wire to compare curl-ups, side planks, front planks, bridges, and bird dogs.  What they found was that the TrA was activated the greatest during front planks with opposite arm and leg raise and that multifidus activation was greatest with bridging.  Although core stabilization exercises should be performed in multiple planes of motion, these two studies highlight the enhanced activation that occurs during “face down” exercises such as front planks and roll outs.

The functional progression of exercises as well as training in all planes of motion are important aspects of OrthoWell’s core stabilization program. Our program will uncover your weaknesses and maximize your strength by progressing through successive levels of difficulty in all directions of movement ie anterior, posterior, lateral, and rotatory. Optimal development of the “local” system ie your functional neutral position and bracing technique(my last post) should occur before attempting to train the “global” or big muscle system.  Unfortunately, most people over-train the global system and need to be re-educated. So be patient as we take you by the “core” and steer you in the BEST, evidence-based direction.

The following videos are examples of some of our functional progressions for each plane of motion(sorry for the  occasional “sideways” view).  I demonstrate a particular exercise and then follow with an exercise of progressive difficulty. Functional progression is very individualized and requires skilled observation to determine competency.  Many thanks to two of my peers, Mike Reinold,PT and Eric Cressey for being very helpful in this regard.

Anterior Core Stabilization Exercises

Anterior/Posterior Core Stabilization Exercises

Posterior Core Stabilization Exercises

Lateral Core Stabilization Exercises

Rotatory Core Stabilization Exercises

1.  Allison GT, Mo4444rris SL, Lay B. Feedforward responses of transversus abdominis are directionally specific and act asymmetrically: Implications for core stability theories. JOSPT. 2008; 38: 228-237.

2. Ekstrom RA, Donatelli RA, Carp KC. Electromyographic analysis of core trunk, hip, and thigh muscles during 9 rehabilitation exercises. JOSPT. 2007; 37: 754-762.

3. Escamilla RF, Babb E, Dewitt R. Electromyographic analysis of traditional and nontraditional abdominal exercises: Implications for rehabilitation and training. Physical Therapy. 2006; 86: 656-671.

4. Faries MD, Greenwood M. Core Training: Stabilizing the Confusion. Strength and Conditioning Journal. 2007; 29: 10-25.

5. Hall L, Tsao H, MacDonald D. Immediate effects of co-contraction training on motor control of the trunk muscles in people with recurrent low back pain. Journal of Electromyography and Kinesiology. 2007; 19:763-773.

6. Hides J, Stanton W, McMahon S. Effect of stabilization training of multifidus muscle cross-sectional area among young elite cricketers with low back pain. JOSPT. 2008; 38: 101-108.

7. Hodges P, Kaigle A, Holm S. Intervertebral stiffness of the spine is increased by evoked contraction of transversus abdominis and the diaphragm: In Vivo porcine studies. SPINE. 2003; 28: 2594-2601.

8. Okubo Y, Kaneoka K, Imai A. Electromyographic analysis of transversus abdominis and lumbar multifidus using wire electrodes during lumbar stabilization exercises. JOSPT. 2010; 40: 743-750.

9. Stanford M. Effectiveness of specific lumbar stabilization exercises: A single case study. Journal of Manual and Manipulation Therapy. 2002; 10: 40-46.

10. Critchley, D. Instructing pelvic floor contraction facilitates transversus abdominis thickness increase during low-abdominal hollowing. Physiother. Res.Int. 7:65–75. 2002.

11. Kavic, N., S. Grenier,  S.M. McGill. Determining the stabilizing role of individual torso muscles during rehabilitation exercises. Spine. 29:1254–1265. 2004a.

 

Low Back Pain -Part 2- Getting Down To The “CORE”

Getting down to the CORE!!

What is your Core?

It is defined as the center or “core” of your body.  It is the “powerhouse” around which all limb movement is performed. It consists of 29 pairs of muscles as well as boney, ligamentous, and discs structures that support the lumbo-pelvic-hip complex in order to stabilize the spine, pelvis, and kinetic chain during functional movements.  In short, it’s pretty important!

 What is the function of the Core?

The core functions to provide both stability and mobility.  It can generate forces in order to complete a sit-up as well as provide spinal stability as you reach your arms overhead.  The muscles that are most important in providing core stability can be divided into two groups:  the primary stabilizers and the secondary stabilizers.  The primary stabilizers are the transversus abdominis in the deep abdominal region and the multifidus muscles which are deep in your back and attach directly to each vertebrae in the spine.  The secondary stabilizers are the obliques in the front, the quadratus lumborum & lumbar paraspinals in the back, the pelvic floor muscles at the bottom, and the diaphragm at the top.

So what does the research say about the Core muscles?

Current research has promoted the transversus abdominis (TrA) and the multifidus as the primary stabilizers of the spine.(1,4,6,8,9)  The TrA is the deepest of the abdominal muscles and, when contracted, it increases tension of the thoraco-lumbar fascia, it increases intra-abdominal pressure, and increases spinal stiffness in order to resist the forces that act upon the spine(4,7) The multifidi span from 1 to 3 vertebral levels and attach one vertebrae directly to another.  As a result, they provide the largest contribution to inter-segmental stability.(4,9) The TrA and multifidus have been found to activate prior to limb movement in order to prepare and stabilize the spine(1,4,9) and it has been shown that the EMG activity of the TrA may be delayed in patients suffering with chronic low back pain (LBP).(7)  The TrA is activated regardless of the direction of trunk or limb movement(4) and this is the reason why performing spinal stabilization exercises in multiple planes of motion can be so effective. A significant reduction in the cross-sectional area ie atrophy of the multifidi as well as poor motor control of the TrA has been associated with patients with acute or chronic LBP.(6.9) Patients with LBP who did not receive exercises specific for the multifidi continued to have atrophy of the multifidi even after 6 weeks of being painfree as compared to the increases in multifidi cross-sectional area in those that performed the exercises.(6,9)  In other words, just because your pain is gone does not mean that your muscles are functionally recovered.  One of our primary objectives in physical therapy is to prevent FUTURE episodes of LBP!  So how do we do it?

How do we test the Core?

Unfortunately, there is not a research-proven, valid testing regimen for core stability.  However, Shirley Sahrmann has proposed a test called the Sahrmann Core Stability Test which is the most common test of function.  It involves the use of a pressure cuff placed under the lumbar spine to measure one’s ability to maintain pelvic neutral while performing five exercises of progressive difficulty.  The chart is included below.

 

How do we perform spinal stabilization exercises?

In physical therapy, we utilize the concept of a neutral spine while performing spinal stabilization exercises.  Every joint has what we call a  “resting” or “open-packed position”. It is the position of a joint when the joint spacing is maximized and the resistance from boney or ligamentous structures is the least. These are the fundamentals of Orthopedic Manual Therapy.  In the following video, we will review the concept of the Functional Neutral Position as well describe how to activate the transverses abdominus and multifidi muscles in mutiple positions.

 

 

NEXT POST:

So what are the BEST evidence-based, core stabilization exercises? 

 

1.  Allison GT, Morris SL, Lay B. Feedforward responses of transversus abdominis are directionally specific and act asymmetrically: Implications for core stability theories. JOSPT. 2008; 38: 228-237.

2. Ekstrom RA, Donatelli RA, Carp KC. Electromyographic analysis of core trunk, hip, and thigh muscles during 9 rehabilitation exercises. JOSPT. 2007; 37: 754-762.

3. Escamilla RF, Babb E, Dewitt R. Electromyographic analysis of traditional and nontraditional abdominal exercises: Implications for rehabilitation and training. Physical Therapy. 2006; 86: 656-671.

4. Faries MD, Greenwood M. Core Training: Stabilizing the Confusion. Strength and Conditioning Journal. 2007; 29: 10-25.

5. Hall L, Tsao H, MacDonald D. Immediate effects of co-contraction training on motor control of the trunk muscles in people with recurrent low back pain. Journal of Electromyography and Kinesiology. 2007; 19:763-773.

6. Hides J, Stanton W, McMahon S. Effect of stabilization training of multifidus muscle cross-sectional area among young elite cricketers with low back pain. JOSPT. 2008; 38: 101-108.

7. Hodges P, Kaigle A, Holm S. Intervertebral stiffness of the spine is increased by evoked contraction of transversus abdominis and the diaphragm: In Vivo porcine studies. SPINE. 2003; 28: 2594-2601.

8. Okubo Y, Kaneoka K, Imai A. Electromyographic analysis of transversus abdominis and lumbar multifidus using wire electrodes during lumbar stabilization exercises. JOSPT. 2010; 40: 743-750.

9. Stanford M. Effectiveness of specific lumbar stabilization exercises: A single case study. Journal of Manual and Manipulation Therapy. 2002; 10: 40-46.