Muscle guarding is part of our wonderfully effective self protection mechanisms. However if left untreated it may stop being part of the solution and become part of the problem. As humans we have evolved very effective forms of protection both from injury and from further injury.
Protection from injury
We protect ourselves from injury by having very fast reflexes. When I talk about reflexes I’m not simply talking about what happens when I hit your knee with a reflex hammer, more about your body’s ability to correct an unexpected action. For example stepping off an unexpected curb could result in a nasty ankle sprain if your reflexes are unable to react sharply to prevent a fall. What happens is the stretch receptors in your muscles, tendons and ligaments sense the sharp change in length as your ankle starts to go over. They send a quick warning to the spine. Which sends quick instructions back to the muscles around the joint telling them to contract and prevent a fall. In the mean time a very slow message is sent to the brain letting it know what is going on. Normally it has all happened and over with by the time your brain even knows what is going on.
Protection form further injury
We protect ourselves from further injury in a slightly more complex way. In acute (only happened very recently) injury cases. Firstly, your sensory nerves send off a huge amount of warnings up the spinal cord to the brain. The joint position sensors (proprioceptors), stretch receptors and pressure receptors have a field day giving your brain over enthusiastic information about the stress that the injured part is experiencing. The brain has to make sense of all of this sensory information and invariably will decide to plonk it all into one category and call it pain. Next the body mounts and inflammatory response which not only works to resolve the injury but also prevents further injury by giving you a healthy dose of pain. Pain is a great inhibitor to movement so while all of this is going on you will most likely move the injured part as little as possible which is great as it allows your body to get on with the important job of healing itself. Inflammation also causes swelling which has the effect of restricting the movement of the area – great news!
Zings and zaps
In acute cases of back pain these defences are normal and healthy and should result in healing within a few weeks. Sometimes the proprioceptors (position sensor nerves) of the small joints of the back (facet joints) send sharp warnings to the brain when we move unexpectedly. As long as everything else seems fine, all we will feel is the occasional twinge, zing or zap as our muscle make a correction. Unfortunately the brain learns from past experiences and from what we have been told and read. It is also influenced by our emotional state and our mental health. All of these have a bearing on how our brain will respond when it receives the occasional sharp warning from our sensory nervous system. If it feels there is any cause for concern it will instruct the surrounding muscles to protect the spine by going into spasm. Under these circumstances the brain has decided that the credible evidence of threat is greater than the credible evidence of safety. However it is not drawing its evidence from the body but more from its own learned experience and fears.
This muscle spasm can last for days, weeks, months and even years and is extremely uncomfortable/ painful for the poor owner of the overly defensive brain. We often refer to muscle spasm as ‘guarding’ because it is a form of defense. Muscle guarding is our own self defense mechanism over-wound; your brains way of wrapping you up in bubble wrap.
This muscle guarding is why we often recommend massage as part of your treatment plan. Ultimately the muscle spasm may have been doing you a favour at one point but once the underlying injury has resolved it simply becomes a pain in the you know where!
You may also be interested in Believe-in-your-back.