The causes of muscle pain vary. Also called myalgia, aching muscles can be caused by an injury, a symptom of a disease or infection, or a side effect of a medication.

Muscle pain can also feel different—aching, cramping, stabbing, or burning—depending on what is causing it.

This article takes a look at the different causes of muscle pain. It will also go over how myalgia is diagnosed and treated, and when you should worry about muscle pain.