| As most of you know, the world of core stabilization | | | | directions occur in almost any sport. Specifically, if a |
| has yielded as much attention as Paris Hilton buying a | | | | posterior perturbation - or unsuspected push from |
| new Chihuahua. The difference: core stabilization | | | | behind - occurs on the spine (lets say a defensive |
| warrants most of the attention it gets. I say "most" | | | | stiff-arm as you lean into a defender in basketball), |
| because as with many catchy terms in the fitness | | | | abdominal hollowing produces the same resistance to |
| industry, it can be abused with the content that goes | | | | the force that no activation does and results in an |
| into defining these terms. However, for the sake of | | | | increase in spinal flexion (vs. 43% reduction of spinal |
| this article I am going to review what I feel to be | | | | flexion when bracing is used) (Vera-Garcia et al. |
| the more logical techniques that are involved in | | | | 2007). As kettlebell lifter and educator Brett Jones |
| stabilizing that snake-like structure we call the spine. | | | | says, if you took a cardboard box on its side and |
| What is Core Stabilization? | | | | loaded it from the top, the box would crumble. Just |
| That's the million dollar question isn't it? If you asked | | | | ask Human Motion's Cliff Harvey what would have |
| 100 different sport scientists that question, you | | | | happened if he drew his stomach in while attempting |
| would get 100 different answers. To me, core | | | | world record lifts in weightlifting: He too would have |
| stabilization is the ability to create uncompromising | | | | crumbled. Furthermore, it is almost certain that if you |
| stiffness around the spine as to not allow any | | | | try to contract only the TA, you will have activity in |
| "energy leaks" during various static or dynamic tasks. | | | | the IO and EO as well. |
| You may agree or disagree with me on that | | | | When the muscles surrounding the spine co-contract, |
| definition, but the bottom line is this: Whether you | | | | they create a stiffness that is greater than the sum |
| are an elite athlete, construction worker, or | | | | of the individual muscle stiffness (McGill, 2006). Thus, |
| receptionist, chances are you will probably go through | | | | during the hollowing procedure, you are actually |
| some sort of back pain in your life. So throw the | | | | inhibiting the potential for optimal stiffness, ultimately |
| 6-pack talk out the window for now and start | | | | limiting performance. You would think that in order to |
| thinking about the spine. If we can ensure the athlete | | | | brace properly and ensure "superstiffness" that you |
| is a column of strength with no loose kinks in the | | | | would need to have an all out contraction during |
| chain, then we can ensure optimal power with minimal | | | | most activities. However, this doesn't seem to be the |
| force loads on the spine. | | | | case as the first 25% of a maximal abdominal |
| First, let's look at the anatomy. | | | | contraction creates sufficient stiffness for most |
| Internal & External Obliques (IO & EO): | | | | activities (Brown & McGill, 2005). During 1RM lifts |
| Involved in flexion, as their forces are redirected to | | | | such as Cliff's world record attempts however, a |
| the rectus abominis (RA) to enhance the flexor | | | | maximum voluntary contraction (MVC) of all the |
| potential. They are involved in lateral bending, | | | | surrounding musculature is necessary to withstand |
| twisting, and stabilization of the lumbar spine (McGill, | | | | the massive force. |
| 1991a, 1991b, 1992; Juker, McGill, and Kropf, 1998). | | | | Let's hug it out: We are dealing with apples and |
| Lastly, they are involved in active expiration (Henke | | | | oranges |
| et al., 1988). | | | | There seems to be a lack of understanding as to the |
| Transverse Abdominis: Rotates thorax from side to | | | | different techniques used between physios and |
| side, increases interthoracic pressure, and is involved | | | | strength coaches for core stabilization and activation. |
| in defecation, urination, childbirth. The TA is also an | | | | When a patient is seeing a physio, they are exactly |
| anticipatory muscle. | | | | that - a patient. Most of the time they are coming |
| Rectus Abdominis (RA): The major flexor of the | | | | from an injury and have consequently obtained faulty |
| trunk. It forms a continuous hoop around the spine | | | | patterns within their muscle sequencing. On the other |
| by transferring the forces from the obliques. The | | | | hand, they could have had years of overuse injuries |
| upper and lower RA are activated together and at | | | | or poor gait biomechanics that has led to muscular |
| similar rates during flexion (Lehman & McGill, | | | | imbalances. Thus, abdominal hollowing seems to be |
| 2001): So throw your "upper and lower abdominal | | | | the technique of choice to help create that control |
| exercises" out the window. | | | | that probably was never there even before the |
| Rotatores: Have a high number of muscle spindles | | | | "injury" brought them to rehab. THIS IS PERFECTLY |
| and thus serve more as a spinal positioner than a | | | | FINE. This is our group of apples. Our group of |
| rotator of the spine (Nitz & Peck, 1986). They | | | | oranges are either these same patients coming from |
| are most active when trying to resist the rotation of | | | | physio or our uninjured group of individuals who need |
| the spine that the obliques and latissimus are likely | | | | to get stronger. Once these individuals are able to |
| causing. | | | | withstand heavier forces and are loaded up with |
| Extensors | | | | weights, abdominal hollowing is no longer sufficient to |
| Longissimus & Iliocostalis: Have thoracic and | | | | lift this kind of weight, while sparing the spine. Thus, |
| lumbar components. These are the major back | | | | the abdominal brace must be taught. Herein lies the |
| extensors. | | | | problem. We are constantly nagging each other |
| Multifidus: Extension of the spine but only through the | | | | (various health care practitioners) about the different |
| correcting of spinal joints that are enduring stress. | | | | techniques used. We need to remember that it is the |
| Line of action actually contributes to shearing forces | | | | needs of the client/patient that is our primary |
| of superior vertebrae. | | | | concern. WE NEED TO EDUCATE AND PREPARE |
| Quadratus Lumborum (QL): Bilateral support wall or | | | | THEM FOR THE NEXT STEP. Physios: Inform the |
| stabilizer for the lumbar spine. The QL is active during | | | | patient that if they are an athlete or they are going |
| flexion, extension, and lateral bending of the spine | | | | to be lifting weights in the future, they will have to |
| and maybe one of the few muscles that doesn't turn | | | | learn both techniques. Strength coaches: Actually |
| off during the flexion/relaxation phenomenon. | | | | integrate both techniques into your training. Isolate |
| Psoas: Major hip flexor. May assist in some | | | | then integrate. It is a great way to allow the client to |
| stabilization due to its orientation (Origin is T12-L5). | | | | achieve initial success (abdominal hollowing) and then |
| Core Stabilization Mechanisms: Abdominal Hollowing vs. | | | | allow them to see the big picture of lifting heavier |
| Abdominal Bracing. The abdominal hollowing technique | | | | loads (abdominal bracing). |
| was essentially developed from a group of Australian | | | | An integrated team approach can produce great |
| sport scientists (Richardson et al. 1999). This | | | | success for the athlete, however, all members need |
| "Queensland group" determined that the transverse | | | | to be on the same page even if their philosophies |
| abdiminis (TA) and multifidus (MT) muscles in | | | | differ. Work with each other to produce the best |
| particular, were very important muscles for motor | | | | results for the client/patient. Your athlete will |
| patterning. They found that following injury to the | | | | ultimately be stronger, safer, and less confused in the |
| back, the TA and MT underwent motor disturbances | | | | process! |
| that had profound effects on the motor patterning | | | | References |
| of the body. Because further injury would just add to | | | | Brown, & McGill . (2005). Muscle force-stiffness |
| these effects leading to a chronic state of poor | | | | characteristics influence joint stability: A spine |
| patterning and pain, the Queensland group argued | | | | example. Clinical Biomechanics, 20(9), 917. |
| that only specific abdominal activation techniques | | | | Henke, Sharratt, Pegelow, & Dempsey, (1988). |
| could break this poor programming. Thus was born | | | | Regulation of end-expiratory lung volume during |
| the abdominal hollowing technique: This technique | | | | exercise. Journal of Applied Physiology, 64(1), 135. |
| involves the drawing in of the abdomen in an | | | | Hodges (1999). Is there a role for transversus |
| attempt to isolate the TA, while relaxing the | | | | abdominis in lumbo-pelvic stability? Manual Therapy, |
| surrounding musculature (RA, IO, EO). | | | | 4(2), 74. |
| The abdominal bracing technique was primarily | | | | Juker, Mcgill, & Kropf, (1998). Quantitative |
| developed - or more appropriately, coined - by | | | | intramuscular myoelectric activity of lumbar portions |
| Canadian biomechanist Stuart McGill. This technique | | | | of psoas and the abdominal wall during a wide variety |
| involves the co-activation of all the muscles | | | | of tasks. Medicine and Science in Sports and Exercise, |
| surrounding the spine (RA, IO, EO, TA, MT, | | | | 30(2), 301. |
| Latissimus, QL, and the extensors) in an attempt to | | | | Lehman & McGill, (2001). Quantification of the |
| create 360 degrees of stability. While bracing, the | | | | differences in electromyographic activity magnitude |
| individual doesn't draw in or push out, but rather | | | | between the upper and lower portions of the rectus |
| "braces" or widens the trunk. If you think about what | | | | abdominis muscle during selected trunk exercises. |
| you would do if someone was to punch you in the | | | | Physical Therapy, 81(5), 1096. |
| stomach: You would set or brace for the punch and | | | | McGill, (1991a). Electromyographic activity of the |
| effectively create stability all the way around the | | | | abdominal and low back musculature during the |
| spine. (For more on abdominal bracing, see Ultimate | | | | generation of isometric and dynamic axial trunk |
| Back Fitness & Performance by Stuart McGill). | | | | torque: Implications for lumbar mechanics. Journal of |
| To Brace or Hollow: That is the question. | | | | Orthopaedic Research, 9(1), 91. |
| Much of the data that came out of the Queensland | | | | McGill, (1991b). Kinetic potential of the lumbar trunk |
| research was misinterpreted. Because they were | | | | musculature about three orthogonal orthopaedic axes |
| working with injured individuals with malfunctioning | | | | in extreme postures. Spine, 16(7), 809. |
| motor patterns, the techniques they came up with | | | | McGill, (1992). A myoelectrically based dynamic 3-D |
| were an attempt to disrupt the faulty patterns and | | | | model to predict loads on lumbar spine tissues during |
| educate the patients on abdominal control. Moreover, | | | | lateral bending. Journal of Biomechanics, 25(4): 395. |
| the TA anticipates trunk, upper and lower limb | | | | McGill, (2006). Ultimate back fitness and performance. |
| movement as well as protects the spine (Hodges, | | | | Waterloo, ON: Backfitpro Inc. |
| 1999). This anticipatory and protective function can | | | | Nitz & Peck, (1986). Comparison of muscle |
| be lost with acute or chronic low back pain. However, | | | | spindle concentrations in large and small human epaxial |
| many clinicians took this information and regarded the | | | | muscles acting in parallel combinations. The American |
| techniques as a way of creating optimal core stability | | | | Surgeon, 52(5), 273. |
| during various tasks. Thus, abdominal hollowing seems | | | | Richardson, Jull, Hodges, & Hides, (1999). |
| to be the preferred choice of many physiotherapists, | | | | Therapeutic exercise for spinal segmental stabilization |
| strength coaches, chiropractors and kinesiologists for | | | | in low back pain. Edinburgh, Scotland: Chruchill |
| core stabilization. | | | | Livingstone. |
| Enter Stuart McGill! Not dismissing the importance of | | | | Vera-Garcia, Elvira, Brown, & McGill (2007). |
| these muscles in their role as intra-abdominal pressure | | | | Effects of abdominal stabilization maneuvers on the |
| creators and stabilizers, McGill and others have since | | | | control of spine motion and stability against sudden |
| argued that this is simply not enough to endure tasks | | | | trunk perturbations. Journal of Electromyography and |
| of even moderate intensity. Furthermore, during | | | | Kinesiology, 17(5), 556. |
| athletic events, unpredictable forces from all | | | | |