From: Terry R.
Question for all physios/exercise enthusiasts fitness pros, and tpis... does the iliopsoas tilt the pelvis anterior or posterior? Chekkies say that a tight psoas increases lordosis (anterior tilt), mark cumford, pete emerson and al vermeil say posterior tilt... opinions? What du you think Joakim?
Both are right... and wrong, i.e. they´re talking about the same thing but neither mentioning the whole picture!
The easy answer is: It tilts according to what you demand and can stabilize during different movement patterns, not according to what you think or said it should... But you will not be satisfied with that, so I widen my answer a bit.
The m.psoas.major are either flexing the upper body, pulling the lumbar spine into extension (i.e. lordosis) or flexing the legs at the hip joint. The m.iliacus can tilt the pelvis because its springs from the os. ilii, the psoas cant, but will secondary to its pull on the lumbar spine. To make some definitions clear. Pelvic tilt is not the same as lumbar extension.
- Pelvic tilt is a anterior rotation of the whole pelvic girdle and
- lumbar extension is a bending of the lumbar spine producing a greater lumbar lordosis!
So, if the lower abdominal muscles in conjunction with the deep posterior (m.bic.fem., sacrotuberal lig., ipsi-/contralateral spine musculature) and superficial (gluteus max et.al) longitudinal system cannot counteract the pull that m.psoas major/m.iliacus (m.m.Iliopsoas) are implementing upon the lumbar spine, the lumbar spine and/or the pelvis will go into extension (i.e. increased lordosis) and/or anterior tilt.
Along with the increasing lordosis in the lumbar spine, the pelvis as a unit will follow into a anterior tilt, when the sacroiliac joint reaches its end range of movement. In the beginning though, it seames that the pelvis goes into a posterior tilt because the lumbar spine are starting its journey into an extension/"anterior tilt" a split second before the pelvic bones does. This is due to closed pack position in the SI-joint, i.e. the sacrum drags the pelvis into a anterior tilt!
The whole debate are ridicoulos and pseudo scientific because all golfers really need good mid section stability both statically and dynamically in three planes of motion, with multiple good neuromuscular programs working at the same time in the area. What we most often want is NO pelvic tilt. To debate on what direction the psoas and/or whole iliopsoas are pulling the pelvis and/or the lumbar spine, without making a specific case out of it and agree upon some basic definitions on anatomical and biomechanical facts, is like saying "my ice cream are tastier than yours!"
If you cannot stabilize your pelvis while asking your prime movers/motors for power, you can´t rock the ball, because your pelvis leaks in one or several planes of motion, that´s the fact!
So back to basic folks (all the above mentioned "gurus"), build upon sound facts, not your narrow business paradigm! The typical American battle for the stupid "I know better, and the rest don´t" title, are nothing else than kindergarten level!
Implementing what works instead of what I wanted to believe, helped me build up/optimize people like Jimmy Lidberg to what he are now! The top ranked wrestler in the world in Greek Romanian wrestling! A sport where the complex functioning of the iliopsoas in conjunction with mid section stability and whole body dynamic stability in three planes of motion is quite demanding.
We need to listen twice as much as we talk, thats why we have two ears and one mouth. After saying so much/writing this for an hour, i now have to listen and read for two hours ;-)
That´s how I see it Terry, hope you´re satisfied with my little effort in widening the picture about "the pelvis and the hip flexors". We need to look behind the strategic war of, who is the best "coach" (i.e. trasch talking other people the american way). There is no best, there is no one way, ther is no this muscle always do just that, there is just a better or worse result opon your implemented knowledge... So, dont by all the stuff I say, that´s just my little implemented knowledge so far, I promise to be better.
/Joakim Dettner Doctor of Naprapathy, Professional Elite Athlete Coach, Founder of Kroppsinvest Institute