Stretching: You’re Not Tight
- Muscles get longer when you stretch.
- The deeper and more intense a stretch, the more flexible you will get.
- Tightness means muscles are short.
- Flexibility decreases with age.
- Static stretching is a great way to begin warming-up.
- Stretching reduces the chance of injury.
You don’t know what you don’t know.
This is very apparent when we talk about stretching and flexibility, a subject shrouded in belief and superstition, where common misconceptions are the cause of many people injuring themselves. Developing flexibility through diligent stretching is primarily the result of increased tolerance to the sensation of stretching; you get better at pushing a little further when you’re at the edge of your range of motion.
Research shows that the part of our body that controls and determines how flexible we are isn’t our muscles but our central nervous system (CNS).The physical length of muscle tissue is irrelevant, although if we pull too hard on it in an effort to increase our flexibility, there’s a chance we’ll move past its ability to withstand the load, damaging tissue, ligaments and creating structural problems that are difficult to resolve.
Flexibility isn’t about using physical force to lengthen muscles, it’s about communication; reassuring our nervous system that a particular range of motion is safe to move into.
The CNS determines how deeply we can move into a stretch based on how safe it perceives us to be in that particular range of motion. It allows us to easily move into ranges where we have moved before and where we have muscular control - our CNS feels safest when it senses we have control over our movement.
Defence mechanisms - such as the stretch reflex- are in place to prevent injury and the movements we do everyday are marked as safe. This means if you sit at a desk all day and then go home to watch TV, these movements become well-known and, even though we haven’t prepared for them, we’ll have no issues moving in and out of them.
If you’ve suffered from an ankle sprain then your posture will be altered to allow that part of the body to heal, even if that means locking up in one area to stabilise the ankle enough to be able to walk on it. This is because our CNS prefers consistency and predictability, and our body will find a way to compensate and feel more stable. If this compensation lasts a long time and isn’t addressed, it becomes the default, familiar, comfy place for the body to be - however wonky you might be! Sometimes it’s difficult to know if we’ve created a mobility problem we’re now relying on, especially when it comes to joint laxity stemming from over-stretched ligaments.
The Stretch Reflex
A stretch reflex, also referred to as a deep tendon reflex or myotatic stretch reflex, is a physical response to the extension of a muscle. In essence, it’s a process that causes a contraction, thereby stopping a stretch. This mechanism, which occurs in two major stages, serves several beneficial purposes, one of which is to prevent injury.
Stretching of a muscle causes impulses to be generated in the muscle spindles. These impulses are transmitted by sensory neurons to the spinal cord, where the sensory neurons synapse with motor neurons; these initiate contraction of the same muscle so that it returns to its original length. Since the reflex action involves the transmission of impulses across only one set of synapses, the response is rapid and described as monosynaptic.
Think of flexibility and stability as two sides of the same coin; by building strength at the end range of movement it means we’re in control and our CNS is happy because it feels safe and secure, knowing you are in charge and can deal with it. If I decide out of the blue I really want to touch the floor in the box splits (because when I was 10 years old it was easy) then it’s likely I’ll be stretching into unsupported territory where I haven’t built up strength and there’s a high chance I’ll injure myself.
Over-stretched muscles lose their ability to contract normally resulting in joint instability, strains, sprains and dislocation. It’s worth considering what you hope to gain from becoming more flexible - what will you do with your new range of motion?
If we train flexibility without also training strength, it means we move into ranges of motion where we don’t have muscular control and have to rely on other mechanisms to support us. The following are a few examples of what can happen when we push past our limits and encounter the worst-case scenarios in our quest to become flexible.
The glenoid labrum is the cartilage which surrounds the scapula to stabilise the shoulder joint and tearing can happen because of the arms being over-stretched and increasing wear and tear on the labrum, and is often only resolved by surgery. A torn labrum can also happen as a result of dislocation or subluxation.
Dislocations and subluxations
A shoulder dislocation or subluxation overstretches ligaments, which then increases the risk of dislocations in the future. Dislocation happens when a joint is out of the socket and must be put back manually and a subluxation is when it naturally goes back into the socket. Ligaments that have been over-stretched also increase the likelihood of dislocations and subluxations as it makes it harder to maintain stability around the joint.
Ligaments attach bone to bone, help stabilise joints and when a ligament is over-stretched or torn, it results in a sprain as the hyperextension over-stretches the ligament, with ankle sprains being one most of us have suffered from. Ligaments don’t like to be over-stretched because this creates instability and laxity in the joint and, although they can repair up to a certain point, this can be slow due to low blood supply and they’re often unable to return to their original length. Referred pain can also happen which is created by ligament laxity around a joint but felt elsewhere in the body and, because the joint is loosened due to the over-stretched ligament, it leads to protective actions such as muscles contracting (which is felt as muscle spasms) to pull the joint back into the correct location, or to protect it from further damage by stabilising it.
Muscle and tendon strains
Tendons, located at each end of a muscle, attach muscle to bone and a strain is when a muscle or tendon is over-stretched or torn. Tendinitis, another tendon injury, is an inflammation of the tendon. Over-stretching can leave muscles and tendons prone to being strained and, in the worst case scenario it can result in a complete tear which will require surgery to reattach it.
Flexibility: how much is too much?
Stretching should feel like a generalised tension throughout the muscle that is being stretched. You should NOT feel:
Pain the next day
Pain in another area (if you’re stretching a hamstring and feel it intensely in your calf)
Compression pain (you pull your knees to your chest and feel it in the front of your hips)
Sharp pain (this could be nerve related)
Research from the past decade has shown that using static stretching (holding a challenging but comfortable position between 10 - 30 seconds) as a warm-up can impair performance, negatively affecting reaction time, strength, speed and balance. It is thought that this may be due to changes in muscle compliance which affects a muscle’s ability to detect and respond to changes, slowing down reflexes within a muscle.
Prevention: What to Do instead of static stretching as a warm-Up
Natural movements are excellent preparation for more strenuous work because moving through a full range of motion requires a continuous adjustment in tension that makes it very difficult to trigger intense muscle contractions.
Elevate your heart rate by walking, running, cycling or swimming and building up intensity.
Specific movements that are related to what you’re warming up for done at a lower level of intensity.
Breathing regularly and deeply communicates to your CNS you’re in a safe place.
A good way to prevent hyperextension and over-stretching ligaments is to maintain a small bend in the joints instead of locking them out straight when stretching.
As with all things, moderation is key; if you are training a lot of flexibility then consider it necessary to balance this out with strength work.