脚下为阴脉所聚,阴所常盛,膝为筋之府,寒则易于挛急,所以足膝部要特别注意保暖,以护阳气。现代研究认为,脚远离心脏,血液供应少,表面脂肪薄,保温力差,且与呼吸道,尤其是鼻粘膜有着密切的神经联系。实验证明,将双足放在4℃冷水中,3分钟后就会出现流涕和喷嚏。所谓“寒从脚下生” The foot of the veins gather, overcast often, knees for the government of the ribs, the cold is easy to make a geriatric, so the foot knee should pay special attention to keep warm to protect yang. Modern research suggests that the feet are far from the heart, with little blood supply, thin surface fat, poor thermal insulation, and close nerve connection with the respiratory tract, especially the nasal mucosa. Experiments show that the feet in 4 ℃ cold water, runny nose and sneezing after 3 minutes. The so-called “cold from the foot”