Acupressure is a traditional Chinese medicine (TCM) technique based on the same ideas as acupuncture. Acupressure involves placing physical pressure by hand, elbow, or with the aid of various devices on different acupuncture points on the surface of the body. Points used in treatment may or may not be in the same area of the body as the targeted symptom. The TCM theory for the selection of such points and their effectiveness is that they work by stimulating the meridian system to bring about relief by re-balancing yin, yang and qi (also spelled chi).
Many East Asian martial arts also make extensive study and use of acupressure for self-defense and health purposes (e.g. chin na, tui na). The points or combinations of points are said to be used to manipulate or incapacitate an opponent. Also, martial artists regularly massage their own acupressure points in routines to remove blockages from their own meridians, to thereby enhance their circulation and flexibility and keeping the points less vulnerable to an attack. Attacking the acupressure points is one theme in the wuxia genre of movies and novels.
Acupressure might work via release of endogenous opioid analgesics such as enkephalin, endorphin and dynorphins leading to alleviation of pain. Acupressure is considered to be a safe form of therapy and side effects are rare.