Eight deficiency is the eight joints of human body, namely elbow, axil, beard and stomach, which is the place where the five internal organs hide evil spirits. Attacking the Eight Deficiencies is to stimulate these eight acupoints, which can promote the circulation of qi and blood, mobilize vitality, enhance human disease resistance, improve immunity, and achieve the purpose of preventing and treating diseases. When you have a cold, your body's immunity drops, and slapping eight deficiency will aggravate your cold symptoms. Don't pat the eight deficiency when you have a cold.