Song Jin (Fang Song) is the most fundamental of all the energetic expressions (Jin) that are cultivated in Tai Ji Quan. Without Song there can be no Tai Ji in the Quan. Basically, you will not be able to sense clearly your internal condition or the energetic flow between dynamic states; you will not be able to establish the source or still center from which the Tai Ji (Yin and Yang) emerges; you will not be able to achieve the therapeutic benefits of practicing Tai Ji as a Qi Gong and neither will you be able to develop Tai Ji style Tui Shou or martial skills to a good level since it is from Song that Peng Jin emerges. Peng being the primary martial Jin and the root expression of the "eight gates" (Ba Men) of Taiji. Achieving Song therefore is fundamental.
In the study of Tai Ji and the acquisition of its principles and skills, the first thing you learn is Form and associated exercises. At some point on your early learning curve you realize that Form learning is a layered process and as you develop structure and physical literacy you will be told constantly to "relax". This should really be "loosen" (Song) and initially refers to the gross sensations of tension that are felt throughout the body in practice. The postures that are complex in coordination and transitioning from one posture to another in Tai Ji training seems to run contrary to this instruction since you obviously need some form of tensioning to achieve any level of form. In addition when you first learn Form, traditionally you learn it in low and deep stance which adds additional tension to the body. Song seems paradoxical yet it is the case that even as you seek to develop form skills you have to move on to the first stages of developing Song skills. Giving up excess muscle and ligamental tension, while maintaining good deep and long posture, structural integration and balance is the beginning. However, contrary to what you might believe loosening/relaxing our posture when under tensional stress increases comfort, integration, balance and precision as well as duration. The key to Song is how much tensioning do you actually need to maintain and manage the structures and dynamics both externally and internally when practicing Form. Structure obviously requires tensional forces since without it the structure cannot be maintained but excess tensional forces are stressful and eventually depleting and damaging. They rely upon physical strength (Li) which is contrary to Tai Ji principles. Finding the right relationship between tension, less-tension and no tension is the art of Song.
By freeing the body (Fang-to Liberate) from excess tensional forces you can experience your body at a deeper and more subtle level. This is a progressive process and there are thresholds of resistance in achieving a full and evolved Song experience. As you progress and begin the work of releasing tension and loosening the body you will encounter physical and mental resistance. Achieving Song is not only giving up tensional forces in the body but also in the mind. Our perception of ourselves can prove to be one of the hardest thresholds to overcome in the achievement of Song.
In the Form practice you need aim to reduce the tensional forces in the upper body and allow the legs to do the hard work of providing the kinetic force however, you must also ensure in accordance with the principles of Yin and Yang (Tai Ji) that whenever increased tension is required to achieve a movement then everything that is excess to that movement is ‘loosened’ or ‘relaxed’. This is easier said than done. Most tensional forces held within the body are deeply rooted in your psychosomatic experiences and can be very resistant to change.
The simple act of establishing a mid line and actively loosening the large muscle groups like the trapezius, the abdominals, the long muscles of the back, the Gluteus etc is the first and most easily achieved level of Song. This can be described as the first phase of the process. A first attempt at this is a significant part of Form training especially when the essential structure, postures and transitions have already been learned.
To deepen the experience of Song it is common to practice a variety of exercises that open the joints and lengthen the muscles and stretch the ligaments as well as begin our exploration of a deeper sense of loosening and giving up to a more relaxed structure and interior. This allows more fluidity within Form dynamics and a deeper sense of rooting and centering (Zhong Ding). None of this however happens without active participation. Song is an active principle achieved by aiming mental focus (Yi) systematically throughout the body. First the muscles and the joints, then the ligaments/fascia then viscera etc. The feeling associated with this can most definitely be described as a "loosening" with a pronounced sense of increased relaxation and a more spacious internal landscape. Next comes an increased awareness of the mechanism of breathing and the restoration of diaphragmatic movement resulting in abdominal breathing. A successful loosening of the interior abdominal pelvic cavity produces a sense of internal sinking when the tensional forces holding the internal organs in place and incidentally often in constriction, are released. The abdomen becomes naturally springy like a drum skin (sorry if you are aiming for six pack abs) and the sensation of ‘Dan Tian’ becomes more real as a center of gravity, a center for reconciling downward and rising forces and also a center of our breathing.
This achievement requires tensional control not only of the large muscle groups but also of deeper layers as well as micro control over the joints and pelvis and their optimized positioning and rotation and finally the fascia and the internal organs. This is a major achievement in training Tai Ji not only from a martial point of view but also from a Therapeutic point of view.
Though this is a good level of achievement it is not however, the full story. The next and most difficult stage is to get the sensations of Song down to the feet. This is hard because the hips, femoral joint, knees and ankles are designed to take the tensional forces required to support our mass in dynamic motion. In a lifetime they do a lot of work and are prone to suffering as a result. Managing our legs and especially our leg joints is crucial especially if we train in any martial system. The principle of getting the sensation of Song down to the feet is the same as for the upper body, it is achieved by loosening excessive tensional forces but, and most importantly also aligning the axis of the long bones and the joints properly so the upper body mass can be transferred to the ground efficiently without resistance as well as ensuring the pelvis is adjusted properly to manage movement and distribution of tensional forces and body mass. When this is achieved, the rising and falling force can be experienced as a clear and unhindered path.
The sensation of Song in the torso is often described as sinking, dissolving or draining. This is a distinct and palpable sensation. Similarly, the sensation of Song descending to the feet is also accompanied by distinct sensations. At first, it feels as though your feet are sinking in wet sand or they feel stuck or rooted to the ground. This is accompanied by a distinctive feeling of lightness in the upper body. The common analogy of a tree or bamboo comes to mind. The roots are deep and firm, the stem (legs) are pliant and structurally strong and the branches (upper body and arms) are able to bend and move freely in the wind. There is a common instruction in Tai Ji training and that is ‘Never forget Bai Hui’. It is worth pointing this out because the sense of lightness and also add here agility that accompanies the full achievement of Fang Song is felt most acutely there. This is because it is the top of our mid line and also the point that draws Yang upwards to maintain our internal and external lift. Excess sinking means prolapse and Bai Hui is key to balancing sinking and rising simultaneously.
Typically, the work (Gong) of Fang Song is done in fixed positions the most notable of which is the ‘Three Circle Standing’ Zhan Zhuang practice is in common use across many systems. It is easier to create the sensations of Song in a symmetrical posture like Three Circle standing before trying to achieve it in the asymmetry of the form postures like the Bow Stance. However, a thorough study of Song requires you to hold a variety of key Form postures to train the body to submit to the state of "Song". Practicing Fang Song is distinctive and requires considerable and intelligent effort. You must also practice Form with Song as the primary focus.
At first there is so much to pay attention to and to manage and nurture. As your skill develops and your mind is able to embrace and direct the whole-body structure and all the sensations that accompany your chosen exercise you start gaining a deeper awareness. Form/exercises and Qi Gong all take on a new meaning as the body begins to experience a deep and pleasurable sense of integration and wholeness, lightness, flexibility and mobility. In the Song state, mind also becomes calm since it has been trained and re patterned in the regular work of Form and Zhan Zhuang. Learning how to stay focused and calm relaxing deeper and deeper within the constraints of the body structure, shape and movements. The mental activity is constantly focused on manifesting the Song principle for sustained periods of time. Indeed, we can say the mind has also achieved in conjunction with the body the Song state.
These sensations transform from gross to subtle as your practice deepens and you grasp the principle. With practice you are able to access deep layers of your psychosomatic experience discovering "resistance", "excess", "depletion" and "stagnation". You learn to focus attention on these experiences and conditions to actively release/transform them. The mental component is very important since Song is both physical and mental and like all things in Tai Ji and Qi Gong bringing the body and mind into a unison is key to your developing Taiji as a Quan and as a Qi Gong.
Finally, although you will be able to achieve a sensation you can call Song, maintaining it in our practice and in an ordinary life is very difficult. Like Chinese language, it is both hard to learn and easy to forget. Managing the state of Song in practice and making it your daily habit is key to your success in the maintenance of good practice. However, and as you might imagine, learning how to apply Song and develop it to a higher level especially as a characteristic of Tai Ji as a martial art is another level.