Educational video describing the anatomy of the tensor fasciae latae muscle. Become a friend on facebook: http://www.facebook.com/drebraheim. Follow me on twitter: https://twitter.com/#!/DrEbraheim_UTMC. 1  Education. 2  Standard YouTube License.
The specific cause of body aches (myalgia) are the interleukins, which are primarily produced by the macrophages. These interleukins cause pain, body aches, hypersensitivity of the nerves, etc. Some of the interleukins (such as IL-2) cause the fever seen during the flu, and probably the headaches. Since these interleukins are produced in response many different kinds of bacterial and viral infections, symptoms such as fever, myalgia, and headaches can be seen in infections by many different etiologic agents.
1 Aging can also cause chronic body aches. Older adults are more likely to have long-term medical problems, such as diabetes or arthritis, which can lead to ongoing pain. For reasons unknown, sometimes not having any illness may also cause constant body aches in older adults.  Some diseases also cause constant body aches.