The Buddha taught qigong as the foundation of meditative concentration
From Qigong as the foundation of meditationAbout 7 min read

When teaching the contemplation of the breath (in the Majjhima Nikāya), the Buddha clearly taught qigong as the first part. "Breathing in, I know I am breathing in; breathing out, I know I am breathing out": simply knowing, with no control. Then "Breathing in long, I know I am breathing in long; breathing out long, I know I am breathing out long", again without control, only knowing.
In the same way, "Breathing in short, I know I am breathing in short; breathing out short, I know I am breathing out short", again without interfering at all, only knowing.
This part is the foundation of supreme qigong. Because the breath is known and not controlled, the ego is stirred very little. If we try to control the breath as we please, the ego is stirred more and more strongly, and the more we practise, the more easily we flare up in anger.
When the practitioner has become used to knowing the breath without controlling it, the Buddha adds a precious secret: "I breathe in experiencing the whole body; I breathe out experiencing the whole body." When we can rest in the whole body, know the whole body clearly and feel the whole body, vital energy gradually appears. At first, though, we feel the whole body only on the surface of the skin and cannot feel the inner organs. After a long time we will feel the inner organs too. The calmer the mind, the more clearly we feel the whole body, inside and out, and the more the latent vital energy shows itself.
Gradually we realise that the source of the vital energy that steadies the body and settles the mind lies in the lower abdomen, not in the upper part, and absolutely not in the head. We then know for ourselves that we should dwell mostly in the lower part, especially the lower abdomen. In daily life, whenever we meet a complicated matter, we quietly keep the mind in the lower abdomen and leave the head empty, and yet we stay calm and clear-headed enough to deal with it, rather than losing our composure as we used to.
After practising for a while longer, we discover the dantian point that Taoist practitioners often speak of as a wonderful point that creates the source of inner strength. This dantian point is not on the skin, as we used to think, but hangs within the lower abdomen. It is like the body's centre of gravity, and also the root of the central nervous system. To know this point and keep the mind on it opens up the central nervous system. This is the marvellous secret of Buddhist qigong. It is also different from outside teachings that tell us to keep the mind on the head, between the eyebrows or on the crown, which later weakens the brain.
At a high level, the sensation of the whole body leads the practitioner to feel as if seeing the parts of the body, even the blood flowing, the pulse beating, the intestines contracting, and so on. In ancient times, the sages discovered the invisible acupoints through just this high level of still-sitting meditative practice.
In truth, the distance between qigong and meditation is only a silken thread.

When a practitioner practises contemplation of the breath in this way, then besides the gradual growth of inner vital energy, the power of clear awareness of the mind appears too. This clear awareness is a state that words cannot describe: it is like tasting food for yourself, or drinking and knowing for yourself whether it is hot or cold.
With clear awareness, the practitioner notices two things: first, a clarity that lets one know the inner mind and the whole body better; and second, constantly remembering the practice one is doing.
First, the clarity to know the inner mind and the whole body better means that the practitioner knows clearly the thoughts arising in the mind and is not swept up in them, as if standing outside them. At the same time the mind stays closely connected to the body without leaving it, always resting in the whole body.
Second, constantly remembering the practice means that the practice of breathing in and out is no longer forgotten. Without this clear awareness, the practitioner often forgets the breath: after practising for a while, wandering thoughts arise and carry the mind away. Once this clear awareness is present, one naturally forgets less and keeps seeing the breath clearly.
Using the practice of contemplating the breath to help the practitioner generate inner vital energy and this wonderful clear awareness is the wisdom of the great Fully Awakened One, and nothing is more precious. Many people who practise meditation like to look for lofty philosophies and neglect this contemplation of the breath, so after practising for a long time their vitality gradually dries up. The Buddha's wisdom and compassion are beyond comparison, so he carefully taught his disciples the contemplation of the breath, that is, qigong, before they entered deep meditative concentration. For in truth, from qigong to meditative concentration is only a silken thread.
Once there is latent inner vital energy and bright clear awareness, the practitioner need only contemplate "The body is impermanent, the mind is ever-changing, truly there is nothing that is me; let go of wandering thoughts", and at that very moment the practitioner has stepped into the realm of meditation, that is all. The practitioner has not yet attained anything lofty, but has truly sown the cause of awakening and liberation by contemplating "the body is impermanent, the mind is ever-changing, nothing is me, let go of wandering thoughts".
In fact the foundation of meditation consists of three things: ethics, merit and qigong. Put more broadly, according to the Noble Eightfold Path, the earlier factors are the root of right mindfulness (meditation). The earlier factors include ethics (right thought) and merit (right speech, right action). Only when these earlier factors (ethics and merit) are complete does right mindfulness and right concentration (meditation) arise.
Everyone must cultivate ethics until it is well established and create a great deal of merit for the world, so as to have enough merit to enter meditation. Those burdened with karmic obstacles from past lives have to struggle much harder. In general, one must repent a great deal and make a great deal of merit in order to have the strength to support the practice of meditation for liberation. To presume that being clever and practising diligently is enough to get good results is truly harmful, because when merit runs dry, the results of meditation gradually diminish and then vanish altogether.
Another extremely important matter is where the aim of the practice is directed.

If someone does not aim at the goal of no-self, they are considered to have left the Buddha's right path. All our conduct must be directed entirely towards the goal of no-self for it to be the Buddha's right Dharma. If we see a master teaching all manner of wonderful things but forgetting to speak of no-self, we should go and look for another. If we do not hold firmly to the goal of no-self, then partway along the road, conceit will arise and destroy every result of our practice.
The practitioner must have a basis in the practice of contemplating no-self. At first, contemplate that this body is impermanent and this mind ever-changing; next, contemplate that nothing is me. The mind is not me, the body is not me, nothing is me. Whenever the mind is clearly aware, immediately remember that this body is impermanent, this mind is ever-changing and nothing is me; let go of wandering thoughts. Practise this all day long until it becomes fluent.