Why You Shouldn’t Stretch Your Hamstrings
For too long the fitness industry has been a proponent of hamstring stretches to relieve tightness in your back and legs. However, what they didn’t consider is that the body naturally gravitates to a state of anterior pelvic tilt and lumbar extension. In layman’s terms, we live our lives with our backs arched and our ribs flared up. It’s comfortable, it’s familiar.
How many times have you spoken, thought, or heard the following sentence?
“Man, my hamstrings are so tight!”
The next logical idea would be to Google some hamstring stretches. You might bend over and reach for those toes, or maybe prop your leg up one at a time on a desk and feel that sweet relief.
The problem is, you just made your problem worse. That’s right, worse.
Take a look at the image above. If you have any back pain, hamstring tightness, or dysfunction in general, chances are you are stuck in this anteriorly tilted position. Look at the hamstrings – they attach on the back of your pelvis and knees.
There is a key function of the hamstrings that is often forgotten, and that is they serve as stabilizers of the pelvis.
Because of where the hamstrings attach, they help to prevent your pelvis from tilting forward.
It seems that people love to stretch their hamstrings, often to the point of overstretching, again, allowing the pelvis to tilt forward. When this happens, demand on your hamstrings increases, making them feel sore and tight, and your risk of injury increases.
What does this mean?
It’s not just your hamstrings that are at risk. When your pelvis is unstable and tilted forward, you will arch your back using the muscles of your low back which often leads to low back pain.
Since your ribs are connected to your spine, as you arch your back, your ribs will become elevated in the front. This will affect your ability to breathe effectively with your diaphragm. Often when this happens people will use their neck muscles to assist with breathing.
This can lead to neck and even jaw pain as well as headaches. These are just a few examples of the effects long or overstretched hamstrings can have on the pelvis, neck and posture in general.
So here’s the question: If we live in a state of constant anterior tilt and our hamstrings are lengthened, WHY are we stretching them?!
Imagine a rope that has two people on each end. If both people are pulling on each end, of course that rope is going to be very tight. Your hamstrings are that rope and they aren’t tight because they’re short and overactive, they’re tight because they over-lengthened and being pulled on all the time from both directions!
What can I do?
People get into trouble when they assume their pelvis is in a neutral position, i.e. not tilted forward.
The reason this is a problem is because when the pelvis is tilted forward, hamstring length can appear to be short, making an athlete think they need to stretch.
For example, a straight leg raise, which is a common test for determining hamstring length works like this: you lie on your back and check one leg at a time to see if it can be raised up so it is pointing straight up to the ceiling (i.e. 90° range of motion).
The common thought is, if you don’t exhibit 90° of straight leg raise, your hamstrings are tight and need to be stretched. But if your pelvis is tilted forward and you perform this test, the hamstrings have actually been placed on stretch before you even start the test.
Here’s an even more interesting thought: The way to fix your hamstring tightness is to turn on your hamstrings.
We need to restore them to a more optimal resting length so they can relax and your pelvis can get out of an overly-rotated state.
So the next time your hamstrings are feeling tight, think about doing a 90/90 hip lift to restore proper pelvic positioning.
A static hamstring stretch will only further put you into your pattern of dysfunction. That is not to say dynamic hamstring stretching does not have a place in warm ups.
Dynamic stretching can be beneficial for getting your tissues to warm up before training or a competition. Always take into account context, your goal, and potential consequences.
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