Core Stability

To start this arti­cle, I would first like you to con­sid­er what core sta­bil­i­ty means to you? As you read this arti­cle you will have a unique per­cep­tion of core sta­bil­i­ty and this may have changed over time. It exists. It doesn’t exist. It is an area of much debate among lead­ing professionals.

Being flex­i­ble with your per­cep­tion allows you to learn, grow and assert more influ­ence. Instead of sup­port­ing or being opposed to core sta­bil­i­ty I won­der if you can start to think in a bit more detail about what you real­ly are try­ing to achieve. 

The first time I ques­tioned this was work­ing in the mil­i­tary; every­day I would come across sol­diers with backs as strong as a buf­fa­lo; often I would hear ​‘I know I should be a bit more reli­gious with my core sta­bil­i­ty train­ing, i know I’ve been told so many times my big mus­cles are strong but its the lit­tle ones that aren’t work­ing prop­er­ly’. Unsur­pris­ing­ly their pain had not changed for years despite doing core sta­bil­i­ty train­ing many times a week for the entire time. 

The real­i­ty is core sta­bil­i­ty is cer­tain­ly more com­plex than we ever ini­tial­ly thought

The real­i­ty is core sta­bil­i­ty is cer­tain­ly more com­plex than we ever ini­tial­ly thought and cer­tain­ly now I would say it is a fair­ly inad­e­quate term to try and the­o­rise some­thing that is as com­plex as human move­ment. The notion that there are some small mus­cles deep inside our abdomen that are cen­tral to pro­vid­ing sta­bil­i­ty to our spine and trans­fer­ring force doesn’t fit with me. So let’s go back to some very basic human move­ment principles.

“We need to start think­ing about the kinet­ic chain and less about core stability.”

Have you ever stopped to con­sid­er how your brain con­trols move­ment? First­ly you give your brain an objec­tive; lets say lift your hip into exten­sion (back­wards), the next thing your brain needs to know is where your mus­cles and joints are from the feed­back that it gets from the recep­tors in these tis­sues. Once your brain receives this feed­back, the brain deter­mines which mus­cles will move the leg, if some­one has over­ac­tive mus­cles in the back and tight hip flex­ors then the brain will then know the resis­tance is too strong from the hip flex­ors for your glutes to over­come but the back mus­cles are strong. There is not much resis­tance from the abs so the back will con­tract to do the move­ment caus­ing back extension. 

The brain has still achieved the desired out­come of mov­ing the leg back­wards but all of the load has gone through the back. If the glutes are in the right posi­tion to con­tract and there isn’t lots of resis­tance from the hip flex­ors the glutes will ini­ti­ate the move­ment and hip exten­sion will be achieved cor­rect­ly allow­ing the spine to focus on its pri­ma­ry role. The body will always find the path of least resis­tance (i.e. the most effi­cient way to move) hence the notion of ​‘some abdom­i­nal brac­ing’ to lim­it move­ment through the core is counter intu­itive to the way that the body moves.

“We need to start think­ing about the kinet­ic chain and less about core stability.”

The preva­lence of clam exer­cis­es or dead bugs is chang­ing and they may still be effec­tive on occa­sions to learn how to utilise cer­tain mus­cle groups but how do we cor­rect move­ment pat­terns? I absolute­ly do believe that alter­ing a person’s start­ing posi­tion will help and we need as lit­tle resis­tance as pos­si­ble. The point that I am try­ing to stress more is that we as a pro­fes­sion need to expand our think­ing a lit­tle more around this top­ic. Think glob­al and con­sid­er how these coor­di­nat­ed mus­cle actions fit into the big­ger pic­ture of human move­ment. Core sta­bil­i­ty has been seen just as the name sug­gests, but pro­gres­sive­ly we need to see it as the link between the upper and low­er body for very com­plex move­ment pat­terns and ensur­ing that ener­gy is con­tin­ued and increased from one mus­cle group to anoth­er as it pass­es between the arms and the legs.

How does the pelvic floor or diaphragm inte­grate with the abdom­i­nals? How does the pelvic floor influ­ence the hips and low­er leg? Could it have an influ­ence on the upper body? Can we co-ordi­nate them with great tim­ing and appro­pri­ate force?

“I mere­ly asked her to rotate her front leg out just 10 – 15 degrees, she hit a serve with almost no pain”

We need to start think­ing about the kinet­ic chain and less about core sta­bil­i­ty. Those of you that are per­haps in the strength and con­di­tion­ing indus­try will be famil­iar with this term. The con­cept of this is that force is passed from one body part to the next. A per­fect exam­ple of this would be an Amer­i­can Base­ball Pitch­er, they start by wind­ing all of their body up into a coil before push­ing of the back foot to start the pitch­ing motion. From there the force is trans­mit­ted through the back leg up into the hip, where it con­tin­ues through the trunk gath­er­ing force. 

Each mus­cle adds its con­tri­bu­tion to the over­all gen­er­a­tion of force into the arm at the pre­cise time to allow a pow­er­ful release of the ball. If these is any seg­ment in this chain that is not work­ing well such as a stiff joint, an incor­rect­ly posi­tioned / inhib­it­ed mus­cles, maybe a mis­fir­ing of one mus­cle then ener­gy will be lost. This will lead to a drop in pow­er or injury. If the body detects that ener­gy is lost it will com­pen­sate by increas­ing force in the dis­tal seg­ments of the chain often caus­ing injury. Treat­ing areas in iso­la­tion by look­ing local­ly at where some­one says they have pain is often inad­e­quate, I believe we need to look at the way the body func­tions as a whole as it is often the painful area that func­tions well. It is this well func­tion­ing area that makes up for what the oth­er areas are not con­tribut­ing to a par­tic­u­lar move­ment. To do this we need to iden­ti­fy areas in the chain that are not func­tion­ing well to restore equal bal­ance. When we com­bine this with appro­pri­ate resist­ed move­ments we can cre­ate real­ly pow­er­ful change.

We need to start think­ing about the kinet­ic chain and less about core stability.

Ear­ly in my career I was work­ing with a ten­nis play­er who had shoul­der pain when serv­ing. She had seen so many ther­a­pists and train­ers to try and rec­ti­fy the prob­lem, con­cen­trat­ing on shoul­der sta­bil­i­ty and core sta­bil­i­ty but with­out any real improve­ments in symp­toms. She would find if she had a local treat­ment on the injured area symp­toms would improve for a few days but would quick­ly come back. Objec­tive­ly I couldn’t find any­thing wrong with her shoul­der oth­er than pain provo­ca­tion tests were pos­i­tive for impinge­ment but the mus­cles were well coor­di­nat­ed, strong and she had an anatom­i­cal­ly nor­mal shoul­der.. All imag­ing was neg­a­tive and her core control/​stability was not bad.

Over the peri­od of 8 weeks she improved her core sta­bil­i­ty sig­nif­i­cant­ly and her shoul­der sta­bil­i­ty even more. With­out being pick­i­er than a French Wine Con­nois­seur in San­tori­ni I was strug­gling to find ways to fur­ther improve this area but her pain remained unchanged. She would come in have physio, the pain would be much improved for a few days, her exer­cis­es would get pro­gressed or adapt­ed for the cycle to hap­pen again the fol­low­ing week.

After get­ting tired of hunt­ing for flaws that were no longer there I decid­ed to take the punt on look­ing at her serve on a court, I know (now) I should have done this a long time ago but I was think­ing I’m not a ten­nis expert and the coach­es would notice any­thing amiss with her tech­nique. I watched a few and there wasn’t any­thing glar­ing­ly obvi­ous oth­er than I thought her left leg looked a lit­tle inter­nal­ly rotat­ed to what I would have imag­ined. I mere­ly asked her to rotate her front leg out just 10 – 15 degrees, she hit a serve with almost no pain. Maybe just a one off I thought. She turned it back to the start point and the full pain was back. Out again and the pain was near­ly gone. After a few more cycles of out and in, no pain and pain respec­tive­ly we had found the fault. Hi it’s a change to focus on low­er limb align­ment, mus­cle imbal­ance and sta­bil­i­ty we rad­i­cal­ly changed the symp­toms allow­ing her to change the weight trans­fer and there­fore the ground reac­tion forces through­out the serve. With the foot turned in she was los­ing a lot of the ground reac­tion force at the start of the kinet­ic chain action. With the foot turned out a much larg­er force was being gen­er­at­ed through the weight trans­fer and she was no longer hav­ing to make up for this else­where in the chain of action (in her case the shoul­der). The force that was hav­ing to be gen­er­at­ed from the shoul­der was too much for the pain recep­tors and soft tis­sue in the area that it was caus­ing pain and tis­sue degradation.

Have you ever stopped to con­sid­er how your brain con­trols movement?

The take home mes­sage for me from this episode was that myself and many oth­er phys­io­ther­a­pists had all adjudged that the cause of her injury be down to her lack of core and shoul­der sta­bil­i­ty. After all there were no oth­er objec­tive signs that were appar­ent for her pain. Full exam­i­na­tion had showed the only prob­lem in her whole body was a lack of con­trol and sta­bil­i­ty. Yet with a vast improve­ment in this area there was very lit­tle cor­re­la­tion with her pain.

It may be worth con­sid­er­ing for a moment, what is not core sta­bil­i­ty? Are there are glob­al exer­cis­es which do not require the abdom­i­nals, pelvic floor and cor­rect breath­ing pat­terns? The lit­er­a­ture in anato­my trains by Thomas Myers real­ly rings true in this sit­u­a­tion. Inter­con­nect­ing tis­sue was all work­ing togeth­er to trans­fer the forces through the body from one seg­ment to anoth­er with the abil­i­ty to con­trol var­i­ous aspects of itself independently.

Despite all of this I do believe that the work she did to improve her strength and sta­bil­i­ty will have had a very pos­i­tive effect on her per­for­mance and injury pre­ven­tion in the long term. I just had a real­i­ty check about my belief in core sta­bil­i­ty. I then realised it was part of a much big­ger pic­ture and that as ther­a­pists and exer­cise pre­scrip­tion spe­cial­ists we need to remem­ber to take our pro­grammes one step fur­ther than the stan­dard. It is imper­a­tive to make sure that we teach peo­ple how to trans­late their new found strength and sta­bil­i­ty in to the func­tion­al activ­i­ties they are need­ed for. Wether this be through tech­nique adjust­ments by work­ing along­side their per­for­mance coach­es or exer­cis­es that trans­late to the sport­ing action. We always have to think towards the whole of the body or the action what­ev­er method we see as the right way for the indi­vid­ual cir­cum­stances and coach­ing tech­nique to get there. This way their work will not be in vain and they will bear all the full fruits of their hard work.