The negative pressure which is formed in vacuum cups stimulates the yu point at local superficial layers and transmits to the whole body to achieve the functions of getting through all the channels and collaterals, promoting vital energy and blood, keeping yin and yang in balance, invigorating the circulation of blood and dissipating blood stasis, reducing the swelling and easing pains, expelling coldness and removing wetness evil, drawing out pus and letting out abscess, and improving the health.