Cupping is the term applied to a technique that uses small glass cups or bamboo jars as suction devices that are placed on the skin. There are several ways that a practitioner can create the suction in the cups. One method involves swabbing rubbing alcohol onto the bottom of the cup, then lighting it and putting the cup immediately against the skin. Suction can also be created by placing an inverted cup over a small flame, or by using an alcohol-soaked cotton pad over an insulating material (like leather) to protect the skin, then lighting the pad and placing an empty cup over the flame to extinguish it. Flames are never used near the skin and are not lit throughout the process of cupping, but rather are a means to create the heat that causes the suction within the small cups.
Once the suction has occurred, the cups can be gently moved across the skin (often referred to as "gliding cupping). The suction in the cups causes the skin and superficial muscle layer to be lightly drawn into the cup. Cupping is much like the inverse of massage - rather than applying pressure to muscles, it uses gentle pressure to pull them upward. For most patients, this is a particularly relaxing and relieving sensation. Once suctioned, the cups are generally left in place for about ten minutes while the patient relaxes. This is similar to the practice of Tui Na, a traditional Chinese medicine massage technique that targets acupuncture points as well as painful body parts, and is well known to provide relief through pressure.