Why do people stretch their hamstrings.
Well, because their hamstrings feel tight.
But, all three hamstrings cross your hip and are attached to your pelvis.
What’s one of the most common postural dysfunctions people have?
An anterior pelvic tilt.
Remember in the previous video we talked about how sitting can cause your hip flexor complex to become adaptively shortened.
Which initiates a compensatory pattern that results in an anterior pelvic tilt.
Which means your pelvic goes up.
Which means your hamstrings get pulled tight.
So, for many people, having tight hamstrings is a symptom of Lumbo-pelvic-hip complex dysfunction, not a cause of dysfunction.
If you have an anterior pelvic tilt your hamstrings will be put on stretch.
This is the tightness that you are feeling – it’s not mechanical, its neural.
Your hamstrings are not short.
If your hamstrings were short, they would pull you into a posterior pelvic tilt.
Things can get a bit more complex when hip rotation and lower leg mechanics are considered, but generally speaking – APT equals Long Hamstrings.
And so, often correcting an anterior pelvic tilt will reduce hamstring the tightness that you are feeling.
And remember also from the previous video that having an APTmeans that your gluteus maximus has become long and underactive.
And that’s because the hip flexor complex has become short and overactive.
So in essence, the hip flexors are stealing neural drive from the gluteus maximus.
And so your body will send more neural drive to the synergists.
And the synergists to the gluteus maximus are the erector spinae and the hamstrings.
And this is how we end up with our 3rd category in muscle imbalances.
Long and overactive.
There are a few muscles that fall into this category.
At least one for each major dysfunction.
The question becomes how do we treat a muscle that has become long and overactive?
It feels good to stretch them, but stretching them is a dangerous strategy.
Because we will just lengthen them further
Which will increase our APT and reinforce dysfunction.
It also makes your hamstrings weaker.
And we will talk about that in a moment.
But this brings up an interesting conversation about why we stretch muscles.
This is where the confusion comes in.
Stretching has a purpose.
And it’s not just “oh it feels good to stretch”.
There’s a purpose to it.
And the purpose of stretching is to return a muscle to optimal length.
If a muscle is not at its optimal length then we won’t have optimal cross-bridging between actin and myosin.
Which means we will have less than optimal force production.
And so we stretch to optimize length/tension relationships.
If we have optimal force-tension relationships
We will then also have optimal reciprocal inhibition.
If we have optimal reciprocal inhibition we will then have
optimal ROM,
optimal force production,
and optimal speed.
And this is how we optimize our performance.
If we stretch muscles and make them too long we end up with
less than optimal cross-bridging,
decreased neural drive,
faulty recruitment patterns,
altered reciprocal inhibition.
And this is going to lead to less than optimal performance.
So now it should be rather obvious that we fix our tight hamstrings not by stretching them, but rather by fixing our anterior pelvic tilt.
Now part of that could involve a direct intervention on our hamstrings
But that intervention would not involve static stretching.
And that intervention would not be applied to all three hamstrings
Lower crossed syndrome is one of 3 main dysfunctions outlined in the scientific literature.
One of the other 3 dysfunctions is pronation distortion syndrome.
Somebody who has PDS will have their feet turned out.
Feet turn out is tibial external rotation.
Biceps femoris does tibial external rotation.
So that means that – between lateral and medial – biceps femoris is usually the tight hamstring.
Semi’s usually not tight.
You don’t need to stretch your semitendinosus and semimembranosus, it’s not necessary.
Biceps femoris – maybe – and if so usually only with active stretching.
So the intervention I recommend for tight hamstrings is
First and foremost fix your anterior pelvic tilt.
Part of that would involve a direct intervention on biceps femoris.
In this video I’m showing you what I do with my athletes who have tight hamstrings.
