Internal Force
Internal force - or that force which is cultivated and produced in the internal martial arts of China (Xingyi, Bagua and Taijiquan, etc.), has its basis (like external force) in the philosophy of ancient Chinese medicine and the science of Qi. Simply stated, internal force is that power which is produced within and around the bone.
The musculature, in this instance, becomes secondary as it is no longer required/used as a prime producer of energy but continues to fulfill its function for defense and mobility. Internal power generation is essentially dependent upon postural alignment. The basic Qigong exercise for the development of alignment trains both the body and mind. The bones must be anatomically placed so that they 'sit' squarely upon one another. The shoulder girdle sits squarely over the pelvic girdle and the pelvic girdle sits squarely over the ankles and heels.
The hips and connected to the shoulders by a naturally 'S' shaped spine and connected to the feet by slightly springy knees. The feet are approximately shoulder width apart and the head sits squarely on the shoulders with the back of the neck extended and the chin tilted slightly forward. The mind focuses upon full, deep breathing, utilizing the full lung capacity. For this to occur, muscular tension in the torso and chest (which prevents full deep breathing) must be relaxed. Initially, tension is relaxed with the focus of the mind upon the tense area.
Tension is acknowledged with the inward breath, and literally expelled from the muscle with the outward breath. An aligned posture does not require muscular tension to stay in place. With deep, full breathing, the heart beat slows down whilst having more oxygen available per breath, per beat of the heart. Tension would normally prevent oxygen transference around the body - but when tension is relaxed, oxygen and energy may flow freely.
When the skeleton is aligned, gravity acts upon the body mass - creating body weight which is pulled downward into the ground. The unhindered body weight travels downward through the center of the bone gently massaging the bone marrow. The bodyweight hits the ground - thus 'rooting' the practitioner like a tree. In this state, it is difficult for an external force to move the body. As the weight hits the ground, an opposite and equal rebound force is created, that travels back up the body, through the bone marrow, again massaging the bone marrow in the opposite direction.
This gentle massaging of the bone marrow, ensures that the bone is both robust and yet flexible, two essential components of a healthy bone structure. Over time the bones toughen. At this point it must be pointed out that an aligned posture is a rounded posture. The bones of the legs, torso and arms assume a rounded posture that forms what is known as 'Internal Iron Vest.' The rounded posture absorbs, deflects and reflects incoming power. As a blow strikes the aligned posture, the incoming power is automatically reflected back into the attacking limb, causing damage to that limb at the point of contact. With the concentration of the mind through deep breathing and postural alignment, the mind brought to a single point - concentrating and relaxing the energy of the mind. As the intellect relaxes, the intuition comes to the forefront and is experienced as an expansion of awareness that goes beyond the physical limitations of the body. Over the years, this expansion deepens and matures - this is Qigong of the mind.
From this still position, the rudiments of internal power are both acquired and cultivated. The next stage is to be able to maintain and produce internal power whilst moving the physical body around through time and space. The structure of the sequential forms of the internal arts exist to exercise and manifest this internal force whilst on the move.
The rebounding, upward force is used to emit energy from the center of the body outwards, whilst the dropping body weight force is used to absorb incoming power. As this force is not dependent upon the rules of muscular power immense force can be produced with virtually no movement as gravity is at work regardless as to whether one is moving or not. No single muscle group can produce the same amount of force created by the bodyweight. Also, muscles tire and need resting, whereas internal force is constant and never grows tired. On a genetic level, human beings are programmed to see muscular movement and prepare to counter it. However, the ability to produce substantial force with virtually no muscular involvement by-passes the natural human instinct for survival. An internal master literally exists and moves within a perceptual gap. If one is not of equal development, then it is very difficult fo confront and counter the internal.