Trigger points form in a portion of the muscle cell where blood flow is reduced and metabolic wastes are not being exchanged for oxygen and nutrients. When enough trigger points are located together, they can form palpable knots in the tissue. Trigger points can cause pain, either in the area of the trigger point, or by referral to other areas of the body. Trigger points can be treated by applying pressure to affected areas, often providing instant relief. Trigger Point Therapy for Headaches and Migraines explains trigger point physiology and then offers a complete program for self-care that includes detailed illustrations of all pressure and stretching techniques. In addition, it provides an in-depth look at the factors that cause and perpetuate trigger points, such as body mechanics, injuries, diet and nutritional deficiencies, hormonal imbalances, and emotional factors, and provides solutions to address each perpetuating factor.