Does cold water swimming benefit or harm your health ?

Tiejun Tang
Cold water swimming refers to swimming in water with a temperature of below 14℃. Does this activity benefit or harm your health? Many people ask me this question when they had known I am a winter swimmer. This question can not be answered with a simple yes or no. Let’s analyse the reaction of the human body to cold water stimulation from the point of physiology. In this way you will gain a clearer understanding.

When people get into cold water this stimulates peripheral vasculature to contract. The blood will therefore be redistributed. More blood will enter the heart, brain and kidney. The blood supply of these important organs will thereby be greatly increased. After leaving the cold water the body temperature gradually returns to normal. The peripheral vasculature dilates. The blood distribution returns to normal. During this process the vascular changed from a state of contraction to dilation. Long term repetition of this stimulation increases the elasticity of the vasculature; this is good for preventing arteriosclerosis. That is why winter swimmers have less chance of suffering from hypertension, heart attack and stroke. Cold water swimming also can increase the blood circulation of skin, slowing down the ageing process of the skin and benefiting peoples’ immune system. Most cold water swimmers never catch a cold.

However, cold water swimming does not suit everybody. If someone has been diagnosed with arteriosclerosis, high blood pressure or other cardiovascular diseases, it will not be suitable for him or her to start cold water swimming. This is because sudden cold stimulation will raise blood pressure, and can increase the chance of heart attack and brain stroke. Sometimes it can even cause sudden death. For patients suffering from rheumatoid arthritis, joint pain might get worse after cold water stimulation. For ladies whom have period pain, winter swimming is also not suitable. For epilepsy patients, any kind of swimming is contraindicated.

Generally speaking cold water swimming is a very good sport for most healthy people. It will benefit you without any harm. For some people already suffering certain diseases such as high blood pressure, arthritis and dysmenorrhea etc. it might bring you more harm than good. For severe conditions of these diseases, cold water swimming is strictly forbidden.

If you are suitable for cold water swimming, you should start during summer time. The frequency of your swim should at least 2-3 times per week, gradually entering winter swimming. When the water temperature is below 5 ℃ you should stay in the water no more than 5 minutes.

If you are aware of the above principles, you will get the idea of whether or not you are suitable for cold water swimming and how to best enjoy your swim.

Wuzhualong – An Efficient Herb of South China

Tiejun Tang

Wuzhualong, also called Wuzhimaotao (Ficus simplicissima Lour), is a native herb of south China, which attribute to Ficus of Moroideae. It has been called Southern Huangqi, Local Huangqi and Five Fingers Ficus. It is mild in nature, pungent and sweet in taste. Its channel tropism is Spleen, Lung and Liver. It has many functions including benefiting Qi and invigorating deficiency; smoothing and releasing Qi stagnation; strengthening tendons and dredging meridians; invigorating Spleen and expelling dampness; expelling phlegm and releasing cough. This herb has been widely used in the southern China, especially in the Canton province. My PhD tutor Professor Tietao Deng, often selects this herb in his clinical practice. It can be used to treat many diseases if combined with various other herbs. Dr. Deng’s clinical experience about this herb, are as follows:

1. To benefit Qi and invigorating deficiency its functions are similar to Huangqi

This herb has a function of invigorating Qi, especially to benefit the Qi of Spleen and Lung. This function is similar to Huangqi so it has been called Southern Huangqi. It can invigorate Qi without causing too much Fire. It is less heating than Huangqi, so it is more suitable for patients of southern China living in a tropical climate. Wuzhualong has often been used to treat symptoms that are due to Spleen and Lung Qi deficiency, such as tiredness, shortness of breath, palpitations, poor appetite, abdominal distension, and loose stools. It is often combined with Dangshen, Baizhu and Fuling. If necessary, it can be combined with Huangqi to increase the function of invigorating Qi.

2. To expel Bi Syndrome, dredging meridians, and a combined purging and nourishing function

In southern China there is more incidents of Bi Syndrome due to the damp weather. This syndrome is mainly due to Wind, Cold and Dampness. In some case it is due to Damp-Heat. It causes joint and muscle pain. Professor Deng often uses Wuzhualong to treat Bi Syndrome. Not only does this herb have a tonic function but the ability to expel Wind-Damp and dredge meridians. It has a combined purging and nourishing function in one herb. It can also be combined with other herbs such as Duhuo, Qinghuo, Sangjisheng, Kuangjinteng, Luoshiteng, Xiqiancao, Weilingxian, etc.

3. Invigorating Spleen and Lung, expel phlegm and relieve cough

Chinese Medicine believes “Spleen is the source of phlegm and the Lung is a container of the phlegm”. The patient suffers from Spleen and Lung Qi deficiency must get cough and/or phlegm. Wuzhualong can be used to treat any cough with or without phlegm, and any phlegm with or without cough. In the case of a severe cough, it can combined with Baibu, Xingren, Zhiyuan; in the case of profuse phlegm, it can combine with Banxia, Qianhu and Jiegeng; for Lung Yin deficiency it can combined with Maimendong, Beishashen, Baihe; for cough with superficial syndrome it can combined with Sangye, Jinyinhua and Lianqiao.

4. Promoting urination to expel oedema; regulating menstruation and promoting breast milk secretion

Wuzhualong can also be used to treat oedema through promoting urination. It is more suitable for the oedema due to Spleen deficiency. In this condition it can be combined with Zexie, Fulingpi, and Zhuling; for irregular menstruation it can be combined with Danggui, Xiangfu, Nvzhengzi and Hanliancao; for scanty breast milk after delivery it can combined with herbs such as Wangbuliuxing, Lulutong, Tongcao and Yimucao, etc.

Besides the use of Wuzhualong as a medicine, it can also be used in food therapy. Many Cantonese boil the herb with pork or chicken soup. It has an effect of strengthening the body, expelling Dampness and dredging the Meridians. It can build immune function and prevent disease from occurring. The health wine that is made from Wuzhualong, has become more and more popular in recent years.

Why this herb has such effective functions? The Medicinal Chemistry research showed Wuzhualong mainly containing psoralen, bergapten, aminophenol, glucide, sterol, and coumarin[1]. The pharmacology research shows that this herb has antibacterial, antiviral, and anticoagulant properties, inhibits cancer and regulates the immune system. Some researchers used Cyclophosphamide to inhibit the immune function of mice. They find Wuzhualong can increase the carbon particle clearance index, increasing the thymus and spleen index and raising hemolysin level. The results indicated that Wuzhualong has an effect of improving the immune system [2].

The weather of the United Kingdom is much different from southern China. In general I’ve observed that most British people have a hot constitution because of dietary or genetic reasons. In my opinion Wuzhualong may have a better effect than Huangqi for invigorating Qi. It is also a good choice for dredging meridians, expelling Bi Syndrome and phlegm, as well as releasing cough. If the herb Wuzhualong interests you, have a try.

Reference
1. Jiang Bin, et al. (2005) ‘The Chemical component research on Wuzhimaotao’. Chinese Traditional and Herbal Drugs. 36, (8), p. 1141-1142.
2. Liu Chunling, et al. (2004). ‘An experimental study on Wuzhimaotao’s effect of immune function of mice.’ Journal of Chinese Medicinal Materials 27, (5), p.367-368.