138
Śrīmad-Bhāgavatam
[Canto 4, Ch. 4]
śanair hṛdi sthāpya dhiyorasi sthitaṁ
kaṇṭhād bhruvor madhyam aninditānayat
kṛtvā —after placing;  samānau —in equilibrium;  anilau —the  prāṇa  and  apāna  airs;  jita-āsanā —having controlled the sitting posture;  sā —Satī;  udānam —the life air;  utthāpya —raising;  ca —and;  nābhi-cakrataḥ —at the circle in the navel;  śanaiḥ —gradually;  hṛdi —in the heart;  sthāpya —placing;  dhiyā —with the intelligence;  urasi —towards the pulmonary passage;  sthitam —having been placed;  kaṇṭhāt —through the throat;  bhruvoḥ —of the eyebrows;  madhyam —to the middle;  aninditā —the blameless (Satī);  ānayat —raised.
TRANSLATION
First of all she sat in the required sitting posture, and then she carried the life air upwards and placed it in the position of equilibrium near the navel. Then she raised her life air, mixed with intelligence, to the heart and then gradually raised it towards the pulmonary passage and from there to between her eyebrows.
PURPORT
The yogic process is to control the air passing within the body in different places called  ṣaṭ-cakra , the six circles of air circulation. The air is raised from the abdomen to the navel, from the navel to the heart, from the heart to the throat, from the throat to between the eyebrows and from between the eyebrows to the top of the cerebrum. That is the sum and substance of practicing  yoga . Before practicing the real  yoga  system one has to practice the sitting postures because this helps in the breathing exercises which control the airs going upwards and downwards. This is a great technique which one has to practice to attain the highest perfectional stage of  yoga , but such practice is not meant for this age. No one in this age can attain the perfectional stage of such  yoga , but people indulge in practicing sitting postures, which is more or less a gymnastic process. By such bodily gymnastics one may develop good circulation and may therefore keep his body fit, but if one simply restricts oneself to that gymnastic process one cannot attain the highest perfectional stage. The  yoga  process, as described in the  Keśava-śruti , prescribes how one can control his living force according to his desire and transmigrate from one body to another or from one place to another. In other words,  yoga  practice is not meant to keep the body fit because any transcendental process of spiritual realization automatically helps one