Research into cramps

At dinner after a long walk recently, mid-sentence I found myself in extreme pain, with which I couldn't move my right calf (unfortunately, I was sat with my legs crossed underneath my chair, meaning it would have been tricky to disentangle them even if the slightest movement wasn't causing agony!). Between shrieks and cries - and a little bit of laughter - my dad diagnosed it as cramp, having had it a few times before. This scene was then followed by frantic treatment of encouraging me to stretch out and move my leg, after all, Sherlock was about to start on BBC1!

This outburst triggered my curiosity, so I decided to try and research into cramps and why they happen, and wrote this report, compiled from a variety of sources, and in my own words:

Cramps

What they are

Cramps are where an already contracted muscle is stimulated to contract further. They range from a few seconds of slight spasming to quarter of an hour of excruciating pain, and can happen either very rarely or, in some cases, every day. The likelihood of getting cramps increases with age, around one third of people over 60 years old, and about a half of those over 80 get regular cramps.

What they are caused by

There are four different types of cramp, the first being true cramp. This is caused by the muscle stimulation nerves becoming hyperexcitable, following an injury to the bone or muscle in that area, exuberant activity (the cramps may occur during the exercise or later), dehydration and body fluid shifts. Tetany cramp is similar to true cramp in its symptoms; however it is where the nerve cells all over the body are stimulated, causing the muscles to spasm all over the body, as opposed to just in one main area. The main cause of this is low levels of magnesium and/or calcium, which results in increased nerve tissue activity. Contractures are when the muscles in one area do not relax and remain cramped for an extended period of time (longer than regular cramps). They are caused by a reduction in ATP in the cells, which then prevents the muscle fibres from relaxing. They can be inherited, they are a symptom of McArdle’s disease, which is a fault within the muscle cells concerning the breakdown of glycogen into glucose (which would then produce ATP). Contractures can also be acquired, through hyperthyroid myopathy, a disease caused by an overactive thyroid. The final type of cramp is the dystonic cramp, in which muscles that are unnecessary for an intended movement are stimulated. These contractions are uncommon, and can be treated with injections of botulism toxin (Botox), which last for several months.

                How they are treated

General treatment of cramps involves treating the underlying condition that causes the cramps. These conditions include unbalanced salt levels, peripheral vascular disease, kidney dialysis and underactive thyroid. However, for immediate pain relief it often helps to stretch out and massage the affected area. On the other hand, there is not much evidence to suggest that this is a good way of preventing further cramps.

References: www.medicinenet.com; news.bbc.co.uk/sport2/hi/health_and_fitness/4275144.stm; www.patient.co.uk > InformationLeaflets

Unfortunately, scientists have not been very helpful, given that there is no certain reason as to why cramps happen!