The two major categories in Qigong practice are: Wàidān (外丹) means “external elixir” and Nèidān (內丹) means “internal elixir.” Wàidān Qìgōng is often called Wàidān Gōng and Nèidān Qìgōng is often called Nèidān Gōng. Since these two terms have been discussed in my earlier books: Qìgōng forHealth and Martial Arts and The Root of Chinese Qìgōng, I will only review their definitions here.

In Wàidān Qìgōng training, you learn to build up the Qì in the limbs through special exercises, trainings, or treatments, and later you learn to allow the built-up Qì to flow back to your body and organs, thereby nourishing the organs and maintaining smooth Qì circulation. This means that Qì is built up on the surface of the body or in the limbs, and then flows “inward” to the body. Common Wàidān Qìgōng practices are limb exercises, massage, and acupuncture. Because in Wàidān you build up the Qì (or elixir) externally, it is called “external elixir.”

In Nèidān Qìgōng, the Qì (elixir) is built up in the body, and then led outward to the extremities. For this reason, it is called Nèidān (internal elixir). Nèidān practice includes ingesting herbs to generate Qì internally, generating Qì in the Lower and Upper Dāntiáns through various methods, regulating the Fire Qì in the solar plexus, building up and then circulating Qì in the Conception and Governing Vessels (Small Circulation) first and later expanding the Qì to the entire body (Grand Circulation), as well as techniques which lead Qì to the marrow and brain to nourish them (Xǐsuǐjīng).

According to the available documents, Yìjīnjīng training emphasizes both Wàidān and Nèidān equally. When you train Yìjīnjīng, you should not train one and ignore the other. Wàidān training is considered Yáng, while the Nèidān is considered Yīn. While Wàidān Yìjīnjīng focuses on training the physical body, Nèidān Yìjīnjīng aims at building up Qì. Both of them must cooperate with and balance each other. When one side of the training is neglected, the balance will be lost, and problems may occur. For example, many external style martial artists have emphasized only the Wàidān Yìjīnjīng and have experienced “Sàngōng” (energy dispersion, 散功) problems. I believe that in order to avoid making this mistake, you should first understand these two subjects and study their relationship.

Wàidān Yìjīnjīng (外丹易筋經)

The purpose of Wàidān Yìjīnjīng is to strengthen the physical body, which includes skin, muscles, tendons, fasciae, and bones. Though the health of the internal organs may also be improved significantly by correct training, the organs are not the primary concern. Technically, the training of the organs is handled by Nèidān training and by the Grand Circulation, which form a combination of Wàidān and Nèidān practices.

In order to reach the goal of strengthening the physical body, many training methods were created. The popular techniques are massage, slapping, pounding, beating, and striking. In addition to these stimulation techniques, many Wàidān exercises were created which specialize in building up the Qì in the limbs. Often, special training equipment was adapted for these exercise sets.

Normally, the first year of training focuses on the central body area, starting in the stomach area with massage, then gradually using the slapping, pounding, beating, and striking techniques. In this year you must learn Nèidān Yìjīnjīng, which teaches you how to build up the Qì at the Lower Dāntián, and later you must circulate it to the Conception and Governing Vessels (Small Circulation). Only after one year, after the center of the body has been trained completely, will the special Wàidān exercises and muscular training of the limbs be started. This will last for the next two years. In these two years, the Nèidān practice should teach you to expand the Qì which is built up at the center of the body to the limbs to complete the Grand Circulation.

The above description should give you a clearer picture of the role Wàidān Yìjīnjīng plays in the training. You can see that the Wàidān stimulation training described above can energize your body to a higher energy or Yáng state.

Nèidān Yìjīnjīng (內丹易筋經)

The purpose of Nèidān Yìjīnjīng is to build up the Qì internally at the center of the body. Later, this Qì is led to the limbs and the entire body. The reason for this is simple: in order to energize the physical body to a higher energy state for Wàidān training, the Qì must be full and abundant. The physical body is like a machine and Qì is like electricity. Only when the machine is in good condition and the power supply is sufficient will the machine be able to perform at peak potential. One of the major goals of Yìjīnjīng training is leading the Qì to support the physical body efficiently to maintain and strengthen its health.

Another goal of Nèidān Yìjīnjīng is to regulate the Qì in the internal organs. When you have completed the Small Circulation, you will have learned how to fill up and smoothly circulate the Qì in the Conception and Governing Vessels. The Conception Vessel is the Qì reservoir which regulates the six Yīn organs, while the Governing Vessel is used to regulate the six Yáng organs. When the Qì in these two vessels is full and is circulating smoothly, the twelve internal organs will be regulated effectively, and the health of the organs can be maintained and improved. Furthermore, if you have also completed the Grand Circulation, you will be able to lead and circulate the Qì in the twelve primary channels smoothly. In this instance, you may use Wàidān exercises to enhance the health of the organs.

Usually, the Nèidān Yìjīnjīng training begins after four months of Wàidān Yìjīnjīng training. It normally takes three to eight months to complete the Small Circulation (Xiǎozhōutiān, 小周天). However, it depends on the individual. To understand this thoroughly, you should very carefully study the Nèidān Yìjīnjīng training, which will be discussed later. After you have completed the Small Circulation, you will start the Grand Circulation (Dàzhōutiān, 大周天), and from there it may take you a short time or forever depending on how deep you want to dig in. When you have reached this stage, you will understand that the Qìgōng field is so deep that the deeper you study, the deeper it goes.

Normally, Nèidān Yìjīnjīng is trained through still meditation. During still meditation, both your physical and mental bodies are relaxed, your mind is calm and peaceful. Consequently, your body tends to be more Yīn compared to Wàidān training. It is only when you are in such a meditative state that you will be able to concentrate your mind on building up the Qì at the Dāntián and directing it to the desired places.

You should be able to see from this discussion why it is so important to train both Wàidān and Nèidān Yìjīnjīng equally. In order to help you settle this in your mind, I conclude with the following important points:

• Wàidān training stimulates your physical body and energizes you, therefore it is a Yáng training. Nèidān training deals with the internal Qì field, the body is relaxed, the mind is calm and peaceful, and therefore it is a Yīn training.
• For correct and safe Yìjīnjīng training, Wàidān and Nèidān must be mutually coordinated to balance each other.
• The time required for Wàidān training is relatively shorter than that for Nèidān training. Nèidān training can last forever, especially when this Nèidān is combined with the Xǐsuǐjīng training.
• Wàidān is easier while Nèidān is harder in both theory and training.

The above is an excerpt from Qigong The Secret of Youth: DaMo’s Muscle/Tendon Changing and Marrow/Brain Washing Classics 3rd Edition, by Dr. Yang, Jwing-Ming, Publication Date October 2022, YMAA Publication Center, ISBN: 9781594399077.