Cupping is a therapy that is especially useful in the treatment of problems of local qi, or blood stagnation in the channels, and is usually performed as an alternative to acupuncture.

The cups that are used are generally of rounded glass construction. The cups are traditionally warmed via a burning taper, held for a very short period of time inside the cup. The cup is then quickly placed over the selected area. Often today, glass cups are fitted with a valve that attaches to a small hand-operated pump, allowing the practitioner to suck out air without having to rely on fire to depressurize the cup first. It also gives them greater control over the amount of suction. The modern name for cupping is baguanfa or suction cup therapy. 

Through either mechanism, all of the oxygen in the cup has been removed and when placed open side down, a vacuum is created, which anchors the cup to the skin and pulls the skin upward on the inside of the glass.

The resulting pressure encourages the flow of qi and blood in the area beneath the cupping, and the local stagnation begins to clear. Cups are generally only left on the skin for shorter periods, but may also be left for an extended time. Cupping relieves muscle spasm by pulling heat to the surface, thereby reducing the inflammatory chemicals that cause local irritation.

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