
Knots, trigger points and super tight muscles…Part 15 of the grumbly muscle blog…
Why do muscles become painfully tight?
I’ve had a couple of clients recently that have come in with one singular muscle that feels, in tone, akin to hard wood under the skin. This is called hypertonic (hyper = excessive amount & tonic = tone/tension) or hypertonia, and this can be accompanied with or without painful spasms.
Normally when we contract a muscle we can see its excessive tone, but at rest this should not be the case.
This excessive resting tone is enough to restrict the normal range of a joint.
So how does this happen?
This is essentially a neural problem rather than a muscular problem…
Muscles have something called a ‘stretch reflex’ which is essentially protective in nature. We also have a ‘tendon reflex’ but more of that another time.
Nearly all muscles have ‘spindles’ in them which detect how much ‘stretch’ they are experiencing and report it directly to the central nervous system (CNS). If a muscle is reporting to the CNS that its under too much stretch this activates the ‘stretch-reflex’ to contract the muscle and stop further stretching, therefore reducing potential damage to the muscle. A good example of this is whiplash.
What causes it?
Overuse and fatigue of the muscle increases pull on the tendons (the white bit of the muscle that attaches to the bone), causing pain. The central nervous system then tells the muscle to contract, to protectively reduce motion (and therefore pain), but humans don’t like having to stop, so this then increases pain.
Muscle overstretching – Having a muscle in a stretched position for prolonged periods can trigger the stretch reflex and potentially cause spasms if that muscle is then stretched too far or too fast. For example, if we’re driving long distances or sat at a desk for long periods, gluteus maximus is in a stretched position and then in order for us to get up or out of the car, the muscle contracts, and we can experience tightness, pain and even spasm.
This is why trainers and coaches advocate dynamic stretching before exercise when the muscle is cold and static stretching post exercise when the muscles are warmer.
Muscle Guarding (splinting) means the muscle might shorten to protect other injured tissues such as ligaments – an example of this is the hamstrings protectively tightening following an ACL (anterior cruciate ligament) injury at the knee.
Muscles become stuck in a pain-spasm-pain cycle.
Prolonged contraction of the muscle (or being in a prolonged poor posture) reduces blood flow, so there is a build-up waste products and irritants which usually have an acidic pH further irritating the muscle.
Strategies to overcome this – Try and increase length of the muscle (stretch it, heat it and or massage it) and try to reduce fatigue of the muscle by strengthening it.
Other causes can be neurological in nature such as muscular dystrophy.