Up to 90% of headaches are tension-type headaches. These headaches are usually felt as a pressure or aching pain of mild to moderate severity. They can be unilateral or bilateral and often occur in the back of the head, on the sides of the heads, and around the eyes. These headaches are most frequently are caused by the muscles of the jaw and neck (See Cervicogenic). The Temporalis muscle is frequently involved in headaches along the side of the head (See Myofascial Pain). It is commonly described as a tight band around the head. Muscle tension is commonly caused by trauma, repetitive strain, misaligned jaw or neck joints, poor posture, nerve impingements, and emotional stress. Poor sleep and diet are also linked to these headaches. As many factors can contribute to Tension-type headaches it is important that not only a thorough evaluation be done, but that contributing factors be identified and addressed. Tension-type headaches may be a trigger for migraine headaches and unlike migraines are usually made better with physical exertion.