I wish that it were that simple, but as with most things it is not. We have all heard the benefits of flexibility from early on in school when we were told that we should be able to touch our toes and turn your head to see what’s behind you.
Flexibility is important, but it depends on what is causing muscles to be tight or restricted to answer the question whether or not you should be stretching them.
One reason that a muscle becomes tight is because they are held in their shortened position for an extended period of time. For example your hip flexors are shorted when you sit for an extended period of time. Muscles that are tight from being in a shortened position respond well to stretching and should be stretched regularly.
Muscles can also be tight from overuse, for example if you push yourself during exercise more than you typically do and then the muscle starts to tighten up on you after the exercise. This type of muscle tightness will also typically respond well to stretching exercises.
When should you not stretch a muscle?
There are a few muscles that commonly spasm or tighten to protect the body, but I am going to focus on the one that I see the most in practice, the hamstrings. Hamstrings often become tight or restrictive to protect the lower back, weird right?
The lumbar spine is made up of 5 bony fingers that are called lumbar vertebrae- the spinous process are the bumps that you feel when you run your fingers up and down your spine. There are discs between each vertebrae these are cushions that are made to absorb the stress applied to the spine. Each disc has a nucleus that has a jelly-like material that can push outward and cause a herniated or bulging disc.
There are a number of things that may cause increased damage to a disc, but the most detrimental is flexing and rotating the spine or bending forward and twisting. When you bend forward the material in the disc is pushed in the opposite direction- just like a jelly donut- when you put pressure on one side it is forced to the other. This is exactly what happens in the spine when we bend forward and the pressure is put on the front of the spine migrating the disc material to the back of the spine where the sensitive lumbar spine nerves are located causing back and leg pain.
What causes our hamstrings to become tight?
Your nervous system knows that bending forward will continue to damage the already injured disc so the brain tells the hamstrings to prevent you from bending forward, by tightening the hamstrings. We often read this sign incorrectly and see this as a need to stretch our hamstrings which continues to injure the disc and perpetuate the tightness in the hamstrings causing a viscous cycle.
What do I do if I have tight hamstrings?
If your hamstrings are tight because you have been sitting for a prolonged time then hamstring stretches may help, but you want to make sure that when you do stretch, you are bending from the hip and not the lower back. This means engaging a hip hinge instead of rounding the lumbar spine. If you hamstring tightness is due to nerve irritation or a disc herniation then you should seek an examination to help determine what the best course of treatment is.