Refining Exercise 4
REFINING EXERCISE NO. 4- This exercise deals with the Area of the Backbone, Pelvic Girdle and the Knees.
Staccato breathing: Five short, quick inhalations totalling one full breath, followed by one forceful exhalation through the mouth, emptying the lungs completely.
Start with three repetitions. Gradually increase by 1 or 2 repetitions every fortnight (depending on how comfortable you feel) until the exercise can be continued for three minutes. Please do not extend beyond this time.
This exercise improves blood circulation by getting rid of blockages in the circulation, which keeps us free from skin problems, varicose veins etc. The better the circulation, the better our health. Also on the physical level, there is transmission of electricity via circulation of nervous impulses through the nerves. Due to muscle tension in the body (which has many causes, some of which are on a much deeper level), these impulses get blocked, the direct result of which is the accumulation of static electricity in the muscles. This in turn leads to involuntary working of the muscles or spasms (it may even result in paralysis). Therefore the smoother and better the blood circulation, the less the muscular tension in our body.
By breathing in installments and to the full, we are improving the elasticity and capacity of the lungs. Like the first exercise, this exercise also helps heart and asthma patients. It also helps in training the lungs for certain essential higher pranayama practices at a later stage on the path of yoga.
The body has its own electromagnetic field and the health of the body is reflected in this field. The stronger the field, the better is the health of our body. This exercise also helps us increase our sensitivity to blood; the more powerful our body's magnetic field and in turn our vitality and health. Many adepts have used this technique of becoming deeply sensitive to their blood circulation, thereby creating vary powerful and attractive magnetic personalities.
Finally, the cells of the brain vibrate with this exercise, which helps enhance and improve our memory, also ensuring general vitality and well-being of the brain.
The astral counterparts of the nerves in yoga literature are called nadis. "Nadi" literally means channel for the flow of emotional energy of prana. The vital forces of prana flow along them (amperage) and they have to be trained to withstand higher pressures (voltage). This exercise helps increase our level of awareness so that on can starts extracting higher quality of prana from the incoming impulses. Without this exercise, the nadis will not be capable of withstanding these high presures and the body/brain system will totally break down, leading to an imbalance.
What is flowing in the nadis is prana, or has been extracted from incoming impulses. But the incoming impulses are dependent upon  Structure (vibrational tone) and conjoined with  identical memory pattern (sanskara). Thus experiential memory too is flowing through the nadis and this experiential memory we call prana. Now in all of us this experiential memory (pattern) is blocked as it is reinforced by memory patterns, and education, our upbringing are all-conducive to creating blocks. These blocks disturb the flow of prana which in turn blocks the flow of nerve mpulses leads to muscular tension, depression, hypertension, blood pressure problems, emotional imbalance, and could also lead to nervous breakdown and paralysis.
Also, it is this debris of million of years of experiential history (memory) flowing in the prana which makes up our psychic nature. This singes all our negative emotions and makes us animals in human form. By doing this exercise, during the forceful exhalation, you are throwing out millions of years of emotional debris, thereby upgrading your psychic nature. So to conclude, as the fourth refining exercise is directly connected with flow, it removes obstacles to flow at all levels: blood, impulses, prana and memory.