Neigong (internal strength^[1] or internal skill^[2]), also spelled nei kung, neigung, or nae gong, refers to a series of internal changes that a practitioner goes through when following the path to Dao, and these changes may be achieved through practices including qigong or tai chi.^[3] Neigong is also associated with xingyi quan.^[4]

Neigong practice is normally associated with the so-called "soft style", "internal" or neijia Chinese martial arts, as opposed to the category known as waigong 外功 or "external skill" which is historically associated with Shaolin kung fu or the so-called "hard style", "external" or waijia Chinese martial arts.^{[citation needed]} Both have many different schools, disciplines and practices and historically there has been mutual influence between the two and distinguishing precisely between them differs from school to school.^{[citation needed]}

This section does not cite any sources. (May 2023)

The martial art school of neigong emphasises training the coordination of the individual's body with the breath, known as "the harmonisation of the inner and outer energy (內外合一)", creating a basis for a particular school's method of utilising power and technique.

Neigong exercises that are part of the neijia tradition involve cultivating physical stillness and or conscious (deliberate) movement, designed to produce relaxation or releasing of muscular tension combined with special breathing techniques such as the "tortoise" or "reverse" methods. The fundamental purpose of this process is to develop a high level of coordination, concentration and technical skill that is known in the martial arts world as neijin (內勁). The ultimate purpose of this practice is for the individual to become at one with heaven or the Dao (天人合一). As Zhuang Zhou stated, "Heaven, earth and I are born of one, and I am at one with all that exists (天地與我並生, 萬物與我唯一)".

Martial neigong is about developing internal power. One way to possibly achieve this is to train particular exercises regularly where the breath is matched with movements of blood or to effect the movement of blood throughout the body. Through these exercises it can be possible to move the blood to a particular area during a particular movement to have a particular result. One of the benefits of martial neigong exercises is the relaxation of blood vessels, nerves, muscles and sinews to help the body move more freely. With the body moving freely and an excess of blood moving to a particular area with little or no effort, the practitioner can possibly develop many benefits. These benefits may include:

• faster recovery from injury to the hands
• an ability to hit with more force
• an ability to move faster (speed is crucial in martial arts)
• the health benefits of being relaxed
• an increase in connection to your legs, spine, arms and head
• increased stamina
• increased athletic ability and health
• regulation of blood pressure
• actually experiencing the channels of the body as they truly are, which can possibly be different from the books
• developing an authentic dantian that is consciously nourished and deliberately formed which is not defined in the books
• greater sensitivity for sparring and fighting

It is important to understand that anyone looking to learn neigong sincerely, is more likely to learn it from a good teacher of internal martial arts like xingyi quan. It is rare to learn authentic Daoist practices from a true master of the subject as quite a lot of the neigong skills are an essential part of a complete system of martial arts. Neigong is not a philosophy, but a technique and an art of inner cultivation. There are intellectual guidelines to the practice of neigong, but it is "Inner Work" which means effort has to be put in to develop real, substantial and testable skills. This is not something that can be imagined or talked about, only from direct experience and hard effort can an understanding of neigong develop.

This section does not cite any sources. (May 2023)

Wuxia and xianxia fiction often portray the training of neigong as giving practitioners superhuman powers. For example, one may use qi to attack opponents without physical contact, fly with qinggong, or harden the body to resist weapon attacks. These can be seen in novels by Jin Yong and Gu Long, films such as Crouching Tiger, Hidden Dragon, Shaolin Soccer and Kung Fu Hustle, as well as video games such as The Legend of Sword and Fairy and Xuan-Yuan Sword.

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• Daoyin
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• Wushu
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