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Freebase(4.82 / 22 votes)Rate this definition: Muscle pain. Myalgia, or muscle pain, is a symptom of many diseases and disorders. The most common causes are the overuse or over-stretching of a muscle or group of muscles. Myalgia without a traumatic history is often due to viral infections.
The most common causes of muscle pain are tension, stress, overuse and minor injuries. This type of pain is usually localized, affecting just one or more muscles or parts of your body. Systemic muscle pain, which you feel throughout your body, is different.It's more often the result of an infection, an illness or a side effect of a medication. Common causes of muscle pain include: 1  Chronic exertional compartment syndrome. 2  Chronic fatigue syndrome.3  Claudication.ystemic muscle pain, which you feel throughout your body, is different. It's more often the result of an infection, an illness or a side effect of a medication. Common causes of muscle pain include: 1  Chronic exertional compartment syndrome. 2  Chronic fatigue syndrome. 3  Claudication.