Tuesday, July 8, 2008

Psoas muscle.. true "core".

The subject of this post is the psoas muscle. Below is a visual:



I will be posting a video (hopefully today) on an exercise plus a stretch that targets this muscle.
The psoas muscles and the abdominal muscles are agonist and antagonist as well as synergists. Allow an imbalance between these two groups and you will run (literally) in to problems. Lower back pain is one of the more common issues from having a tight psoas. Kerrie Wlad to a white courtesy phone...
Function:
In the standing position, contracted psoas muscles move the pelvis backward; the abdominal muscles move the pelvis forward. (antagonists)

In running, the psoas muscles of one side initiate forward movement of that leg, while the abdominals bring the same-side hip and pelvis forward. (synergists)

The psoas major muscles pull the lumbar spine forward; the abdominal muscles push the lumbar spine back. (antagonists)

The psoas minor muscles pull the fronts of attached vertebrae (at the level of the diaphragm), down and back; the abdominals push the same area back. (synergists)

Unilateral contraction of the psoas muscles causes rotation of the torso away from the side of contraction; abdominals assist that movement.

Dr. Ida P. Rolf described the psoas this way:
Let us be clear about this: the legs do not originate movement in the walk of a balanced body; the legs support and follow. Movement is initiated in the trunk and transmitted to the legs through the medium of the psoas.
Now.. as athletes we need to really let this quote sink in a bit. Legs follow the core.

Something else to ponder- When the thigh is farthest back, in running, the ankle is most dorsi-flexed. That means that the calf muscles and hip flexors are at their fullest stretch and primed by stretch receptors to contract. This is what happens in well balanced running: assisted by the stretch reflex, the plantar flexors of the feet put spring in the step, which assists the flexors of the hip joints in bringing the thigh forward.
NOW- Here's what makes all of this interesting: when the plantar flexors fail to respond correctly, bringing the thigh forward falls heavily upon the psoas and other hip joint flexors, which become conditioned to maintain a heightened state of tension and readiness to contract, and there we are: tight psoas and back pain. (Note that ineffective dorsi-flexors of the feet prevent adequate foot clearance of the ground, when running; the hip flexors must compensate by lifting the knee higher, leading to a similar problem.)
So we can now say- responsibility for problems with the psoas falls largely on the feet. No resolution of psoas problems can be expected without proper functioning of the lower legs and feet. Foot plant and lower leg strength are critical. I have posted (in the past) a video of jumping rope which I feel is one of the best (if not the best) exercise for teaching proper foot plant and also strengthening the lower leg.

15 comments:

kerrie said...

hmmmmm....does this mean that i have to get a jump rope? interesting about the feet - i just recently stopped taping mine so maybe that is to blame.

are baby oil and thongs going to be involved in this video?

beth said...

Pso, as you mention, it all starts in the core....got it. i became intimately aware of my psoas last year upon stress fracturing the femoral neck...the two are attached i think...

i really like the lower leg excercises/stretched in the video...need to do them more!
thanks.

jonathan said...

I noticed, while learning about the so-called psoas, that you got a hair cut. Nice.

Lucho said...

Beth- I saw the video of your race on your blob and counted your cadence at about ~80.. it may be possible that you are losing energy and increasing your cadence is more efficient.
Jonathon- I like being able to wash my hair with a baby wipe..

Dave said...

Lucho, what's the best way to increase cadence? I did a treadmill session yesterday with special attention to form (used the mirror and all). I find that when I did my cadence checks I was pretty consistent at about 85. When I tried to get up to 90 plus it just made more tired. Is it possible that my "natural" cadence is just lower than normal? Thanks for any info!

Lucho said...

Dave- It is quite possible that your natural cadence falls at 85, which isn't too bad. Remember though that anytime you change an ingrained "habit" it will feel weird. If you look closely at the physics of over striding it makes sense to shorten your stride and have your feet plant beneath you. Take another look when you are running at 85 cadence and see if you are "braking" with your heels when they touch the ground. If they are then, natural or not, you might be able to increase your economy.
The fatigue and higher HR are from not being efficient at the faster stride rate- it may sound contradictory to what I'm saying- but if you get "good" at a higher cadence then you may run faster.
T

Lucho said...

Sorry- I forgot to answer your question.
Think "conscious thought". Simply making the effort to increase your cadence is the basic way. Count as often as you can or use a metronome which is a great tool. Jump rope single legged 2 times per week for just 1 X 20"-30" each leg to start with (don't be a hero).. then increase the time or the reps as you adapt.

BRFOOT said...

What I've noticed, and now makes more sense. When I start getting tired. My retarded left leg starts having trouble with dorsiflexion, I really have to concentrate to keep my foot plant more underneth me. If I don't and I throw my leg out there just that little extra so that it lands flat on it's own. Then my overall form starts going to shit. hips get sore, knees hurt. What I wonder is if anterior tib muscles are weak which I don't think so or if it because of repeated ankle injuries on my left leg.
Your new look makes me think a song lyric "grow it long shave it off" can you name that tune?

Lucho said...

B-
"Life is hard, never soft
I need a change, I need it quick
Before it makes me sick"..
From what I can remember.. 1995 was a good year for me.
Have you ever tried single leg standing exercises? Simply balance on one foot for 45"-1' with out putting your other foot down. Do this barefooted (or brfooted). Try it and you'll see that it's a good exercise for lower leg strength.

kerrie said...

well, not quite a thong but i am glad to see that you brought the brown shorts out for the special occasion...

so i tried the stretch and can feel it but it pinches on the leg that is pulled up - something on/in/around my hip flexor. is that supposed to happen?

Lucho said...

Kerrie- No.
Maybe Friday we can go over the stretch. Group MAF test at 7:00am in Niwot.

Lucho said...

One more thought on cadence: by taking fewer steps you are decreasing the load placed on your legs with each step. A higher HR may not be indicative of "good or bad".
With cycling- a higher cadence generally yields a higher HR which indicates stress on the aerobic system.. but this also lowers the stress on leg muscles. Your aerobic system doesn't really "fatigue" in the classic sense so this may be ok. Your leg muscles on the other hand WILL fatigue and you'll use more glycogen with the decrease in cadence.

BRFOOT said...

I can really feel all of those little muscles in my feet fire when I do the 1 leg stands. I will test drive this for a little while and see if it helps. thanks

Lucho said...

brfoot- Another twist you can add is to close your eyes. Huge difference.

BRFOOT said...

Kind of a field sobriety test for runners.