Why Does My Hip Flexor Stretch Stop Holding After 40?
Can You Open Up Joint Space Without Injections Or Surgery after age 40?
Understanding what stretching gives you and what it does not give you when it comes to the hip flexor muscle after age 40.
The Healthy Movement Podcast
“Stretching the hip flexor muscle is the most common tool used today for hip flexor tightness.” Kim Nartker
By Kim Nartker
Read time: about 10 minutes
In episode #250 Kim continues a series on the healthy hip because almost every person walking into her studio now arrives with a hip restriction of some kind. This episode answers the first question she gets. Why does the hip flexor stretch stop holding after 40. She went through the stretching research and she reviews what she finds and what she sees is missed in the research. How much stretching it actually takes for the stretch to hold.
Then she shows what those same researchers found when they stood the person up and asked them to run.
A note on the research. Every study named here is real and Kim reports what it found and not what she wishes it had found. Where she is describing what she sees in her own studio she says so plainly. She does not diagnose or treat or cure or prevent any medical condition.
The Short Answer Your hip flexor stretch is a great tool but, Is it doing what you are looking for it to do?
Stretching improves your range of motion for as long as you keep stretching. The research supports that when you stretch you improve your ROM.
What stretching does not do is restore accessory motion. Accessory motion is the glide of the bone inside the joint capsule. This motion is not under your voluntary control and no muscle performs it. We have been taught to focus on the muscle, to stretch the muscle, but the muscle is not tight for no reason. Have you ever asked yourself or a professional that told you that you are tight, why am I tight? And did you get the answer your aging, or do you sit a lot?
I see the research, I see people in my studio that come in one day with restricted hip joints and these people are all experiencing the same tightness and they are not all old.
What You Have Been Told About Your Hip Flexor
Stretch it
Sitting Causes your hip flexor to tighten
A tight hip flexor muscle pulls the pelvis forward.
You feel tight in the front of your hip. Or your low back bothers you. So you stretch.
Somebody told you the muscle is short because you sit too much. Somebody else told you the hip flexor pulls your pelvis forward and that is why your back hurts. Both explanations end in the same instruction. Stretch it.
And stretching is the safest thing anyone can tell you to do. You cannot hurt yourself doing it. It feels better while you do it. So it became the default answer everywhere.
The problem is not the advice. The problem is what are you looking to gain with the stretch, what is actually causing the tightness, (it’s not sitting alone….and its not aging) there is more that I will break down in order to help you better understand your hips. And what age are you when you feel the tightness signal.
I dug into the research on stretching the hip flexor. What the stretch does do, what it doesn’t do
What I found is that stretching does improve ROM. But ROM gains do not stick so you have to stretch over and over to maintain the ROM gains.
I also found in the research that the people that were stretched passively and stretched on their own gained ROM in both passive and active stretching, but none of the stretching transitioned to function. Meaning the stretching gains were limited to feeling looser, after stretching.
What Not One Of Those Studies Measured was how to improve movement and function. Everyday I see advertisements promoting move better, but the modality used is stretching.
Stretching the hip flexor is very effective for post sport and workout recovery. But the myth that the stretch will improve muscle length has not been proven in any study that I found.
As we age there are changes that occur in both the joint and muscle, but age is not the only factor for those changes. The joint changes by stiffening, losing centration, leading to instability. The muscle function declines and no one can answer why this happens. From the research that I have found, I speculate that joint and muscle decline predictably in people that don’t get their joints tested for a restriction. I do not have proof of this, but I do see major improvements in testing my clients joints and in their hip especially I see them lock down without any reason at all and in those people that do not have a provider testing their joint restrictions, these people get tighter, and tighter and not only lose ROM in their hips, they lose function in the joints and muscles.
We have great research on people that have been diagnosed with arthritis, or other diagnosis, but these people did stretching at some point in life, and the stretching did not hold. This is what you are experiencing right now. So if stretching was not answer for all of those people that ended up in surgery, I ask, will it work for you.
In the episode I did a deeper dive and discussed Two Kinds Of Stretching
Active Stretching and Passive Stretching (Assisted)
There is active stretching which is you stretching yourself. You go to your own tolerance and you stretch fascia and muscle. It is useful and it is limited because you can only take yourself so deep.
Then there is passive stretching which is somebody trained doing it to you. Fascial stretching. Muscle stretching. PNF. Contract relax. In physical therapy the same thing is charted as passive range of motion. In a stretching studio it is sold as stretching. All of it works on soft tissue and soft tissue means muscle and fascia.
Both of those live in the layer you can reach the muscle layer.
The deeper layers below your hip flexor muscle lives a ligament, a joint capsule and bones that are supposed to move. Those surfaces are not reached with stretching your hip flexor muscle.
So how do you stretch the joint to improve the health and function of your hip flexor muscle?
Joint stretching which is a different type of stretching stretches the surfaces below your muscle. Physical therapists trained in it call it joint mobilization. A chiropractor does it with an adjustment. A doctor of osteopathic medicine does it with manipulation. My own work is much gentler than any of those and I am stretching the joint capsule so the bones glide better and the nervous system can turn down the protective response.
Here is what I want you to notice. Every form of muscle stretching is available at scale on every corner in America. Joint work is available for pain relief, but not used to restore and preserve joint and muscle health. I have gone looking and I have not found it offered as an ongoing testable service anywhere. When I say testable service, I am referring to testing for joint restrictions and tracking our movement health scores so that we can see if our stretching is working or if we need to do something else.
So the muscle layer has plenty of providers selling this service. The layer below the muscle has providers that sell pain relief. We are missing services at scale that help us restore and preserve our joint and muscle throughout our lives.
Why is this important?
After 40 you are not only losing flexibility in your hip flexor muscle, You are losing range of motion and accessory motion and strength and power at the same time in your hip joint. The restriction begins first, this alters the message to the muscle and causes a cascade of loss in the muscle. And the fast twitch fibers go first. Aging muscle loses type two fibers preferentially and those are the fibers you use to move quickly and catch yourself. We lose those first.
When general loss of muscle mass and strength progresses far enough it gets called sarcopenia. Then we are encouraged to build strength, while preservation of muscle is much more effective and helps us keep our movement quality. Once you lose muscle to rebuild the muscle it takes years.
Here is the practical difference I see. My twenty and thirty year olds still have muscle mass and muscle function and enough capacity to compensate their way through a restriction in the joint. They stretch and see the limited results, but do it anyway, because they are told to.
My clients over 40 have joints that have been restricted for twenty or thirty or forty years and they have multiple areas of inhibited muscle stacked on top of that. The loss is more layered in someone over forty, but the loss is not due to aging alone. This is why when you are over 40 and stretch your hip flexor muscle you don’t see the same benefits you did at 20 and 30. Your joints and muscles have been in decline and now you have lost a lot of muscle mass. That mass is a function that is lost with atrophy. Research has proven that the hip flexor muscle starts that process in our 30’s.
What Do I Do With Someone Over 40?
I open the accessory motion in every joint in the body and not just the one that is tight.
I use a technique that works with the nervous system to release the protective response that has the joint locked down. It is gentle and it holds better than stretching the psoas ever did for me. I stopped stretching that muscle years ago.
I load the hip twice a week and I want it as heavy as you can safely handle. That is joint health and bone health at the same time.
I test movement for muscle inhibition which is the most complex part of what I do.
I load tendons slow and heavy and I use in range holds and slow eccentric lowering.
And when I work a hip I program the low back and the foot and the ankle with it because those joints talk to each other. Replacing one joint and ignoring the three around it is how people end up back in a clinic two years later.
That is what I see in my studio. It is a group of people I follow closely and it is not a controlled trial and I am not going to pretend otherwise.
You Did Not Do Anything Wrong Almost every new client says a version of the same sentence. I have no idea how I got here. I did not fall. I did not hurt it. I woke up one day and my hip was tight.
They are right. They did not do anything wrong. They did what they were told and it worked on the muscle until the muscle loss did not allow for improvements.
You cannot feel a joint restriction. There is no pain and no pop and no moment you can point to. Your body compensates immediately and that compensation is what lets you feel normal while the loss continues in the joint and muscle.
Nobody tests the joint for a restriction. Fitness measures your output. Healthcare measures pathology and diagnosis. The restriction sits in between those two and gets measured by neither. That gap is where the Silent Shutdown Cycle does its work.
Where This Leaves You If your goal is range of motion then stretch. Stretch consistently and understand you are renting the result and the rent is due every week.
If your goal is to still get off the floor at seventy five then range of motion is not the number you should be tracking.
Here are the two questions I want you to ask before you agree to any treatment for tightness.
What movement can I expect from this treatment?
And can I restore and preserve my joint accessory motion with the treatment you will be providing.
We track cholesterol. We track blood pressure. Almost nobody is tracking the system that decides whether you can still get down on the floor and back up when you are 80.
Next week I continue the hip series and I go deeper into what the restriction actually does to the muscles around your hip. Subscribe so you get access as soon as it drops.
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