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The Clinical Mystery Behind the “Charley Horse”

Have you been waking up in the middle of the night due to excruciating pain in the legs? You may be experiencing muscle cramping, better known as a “charley horse” which is an involuntary muscle cramping or spasm that occurs typically in the calf, thigh or hamstring musculature. The reason behind why this miserable interruption of sleep occurs remains a mystery to most who suffer from it. There is no one specific reason for why they occur, but there are several factors that could be contributing to why you might be suffering from charley horses.


In order for the muscles to properly fire, they require an even ratio of electrolytes flowing throughout your body’s cells. Electrolytes need to be maintained at a certain level at all times for the optimal muscle function. When you are experiencing any type of excessive fluid loss (such as vomiting, sweating or diarrhea) you are at risk for losing electrolytes which can lead to this imbalance. In addition, exercise in extreme conditions like heat and humidity forces the body to lose its hydration and electrolytes and a faster rate, therefore facilitating the occurrence of muscle cramps.


If adequate daily stretching is not performed following exercise, the muscles and tendons will be reduced in length, causing increased stress on the muscles. Tight calf muscles are common, which is where most people experience their cramping. To address this, make sure to routinely stretch following exercise and before going to sleep. The classic calf stretch is acceptable, but in addition, foam rolling the calves will be even more beneficial.


If you are exercising in extreme heat conditions, or overexerting the muscle in a way that its not prepared for, fatigue will likely take over. Continuing exercise through fatigue will decrease oxygen supply to the muscles leading to insufficient circulation. The body needs adequate time to recover so that the muscle pump can get back up to speed with oxygen delivery to the tissues. Be cautious when exercising that you are not overworking the muscles in extreme weather situations and taking rest breaks when necessary.


Taking any medications including: lipid-lowering agents, antihypertensives, beta-agonists, insulin, oral contraceptives, or alcohol, can lead to muscle cramping. Even though cramping is an associated side effect, talk to your doctor if you think you may be experiencing cramps in result of a medication you are taking.


Sometimes the way you sleep might be the reason behind why you are experiencing muscle cramping. Many people prefer to sleep with their feet pointed which can trigger cramping in the calves. This puts the calf muscle in a more shortened position, adding to the strain placed on the muscle. To address this, you can sleep on your stomach with your feet hanging over the edge of the bed. Either of these positions will place the calf muscle in a more optimally lengthened position.

These are just some of the many theories out there as to why charley horses occur. It is likely that one or many of these can apply to your situation. For the most immediate and acute remedy, try to quickly bring your toes towards your chin while you are experiencing the cramping. For pharmacological treatment, ask your doctor about what kind of options are out there that might work for you.

Although charley horses are not a medical emergency, they should be treated appropriately as these cramps can interfere with not only your athletic performance, but also quality of life and sleeping habits. Don’t let charley horses impose on your happy and healthy life!


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