Perhaps the most common cause of a stiff neck and headache is overuse of the muscles in the neck and shoulders. The tension caused by the tight muscles can lead to a tension headache, which can last for several hours or even a day or more if left untreated. Stress-induced tightness in the neck and shoulders can also cause a stiff neck and headache, as can poor posture or poor conditioning of the muscles in the upper body and back. Illnesses such as the flu, a common cold, or sinus infections can also lead to a stiff neck and headache.
Injuries occur often in the neck and shoulders, particularly among athletes or active people. Muscle strains occur when the small fibers that make up a muscle begin to tear, leading to tightness and pain. This tightness can lead to a stiff neck and headache if such an injury occurs in the neck, shoulders, or upper back, and it is especially likely shortly after the injury occurs. Treating the injured muscle should help alleviate the stiff neck and headache pain, though in some cases over the counter painkillers may be necessary to dull the aches. Icing the affected area and resting it for several hours or even days should help heal the injury quickly.
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Poorly conditioned muscles in the neck and shoulders are more likely to become tired and tight, leading to a stiff neck and headache. To avoid this, it is important to strengthen and tone those muscles regularly, as stronger muscles are less likely to tire quickly and consequently tighten up. A regular exercise routine, however minimal, should help alleviate regular occurrences of pain in the neck and head. One should be sure to examine daily routines as well, as poor posture can lead to tension in the neck and shoulders, which can in turn result in a stiff neck and headache. If this is a problem, one should consider purchasing an ergonomic chair that supports the back and neck.
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Illnesses often lead to stiff neck and headache for a variety of reasons. Flu sufferers often complain of these symptoms along with plenty of other unpleasant symptoms. The common cold can also lead to such pain, and sinus infections and allergies can both lead to headache and stiff neck, especially if the sufferer is coughing and sneezing regularly. The strain on the head and neck, as well as the congestion associated with such illnesses, can cause discomfort in the head and neck. Pain medications and other cold remedies often help clear up such discomfort.