Kriya Yoga is effective as it works directly on the life force deep in our spines and helps to attain the spiritual growth. All Yoga techniques work with this vital energy, often indirectly. The yoga postures help to open up the spinal channels and balance the energy in the spine. The breathing exercises or Pranayama aids to awaken the energy.
The Kriya Yoga technique is more direct than other Yoga techniques. The practitioner of Kriya Yoga Technique can control the life force by mentally drawing the energy up and down the spine. According to Paramhansa Yogananda one Kriya takes about half minute is equivalent to one year of natural spiritual growth.
Yogananda describes the technique of Kriya Yoga in his `Autobiography of a Yogi` as "The Kriya Yogi mentally directs his life energy to revolve, upward and downward, around the six spinal centers.... One-half minute of revolution of energy around the sensitive spinal cord of man effects subtle progress in his evolution; that half-minute of Kriya equals one year of natural spiritual unfoldment."
The Kriya yoga Technique is taught through initiation. It needs the guidance of a guru or teacher as Yogananda said in his autobiography "Because of certain ancient yogic injunctions, I cannot give a full explanation of Kriya Yoga in the pages of a book intended for the general public. The actual technique must be learned from a Kriyaban or Kriya Yogi; here a broad reference must suffice."
Yogananda states that the Kriya Yoga Technique brings the practitioner to the source of inspiration and clears the brain and stimulates it, enhances knowledge and strengthens medulla and open the spiritual eye. The Kriya Yoga technique greatly magnetizes the body. By this method the blood becomes oxygenated that the breath rate becomes slower and slower. Thus student of Kriya Yoga lives more by the word of God or Cosmic energy. When the current is sent through and around the spine the brain can percept the feeling of God. These things can occur through the control of prana exercises of Kriya Yoga Technique, which are not ordinary breathing exercises. A huge number of students have practiced the techniques of Kriya Yoga with the greatest benefit to their spiritual and moral growth.