Nauli
This is a technique to strengthen the abdominal and digestive muscles. It massages the internal organs and brings radiant health to the entire body. When practicing Nauli the muscles of the abdomen, back, legs and hands are used. Most of the effort is in the rectus abdominal muscles. These muscles, when they are functioning properly, play an important role in protecting the internal organs, bowel functioning, vomiting, and giving birth. Their strength also helps to prevent hernias. In the "Gerhanda Samhita," the Nauli is replaced with Lauliki, which is a simpler exercise that requires less practice.
You should learn Nauli from an authoritative teacher, but if you do decide to practice it alone stop immediately if you feel any pain.
You must have good control over Uddiyana Bandha before starting this practice.
You can practice Nauli in different meditation postures, but the best and easiest way to learn and practice Nauli is in the squatting position.
Technique:
Stand with your legs spread shoulder width apart.
Bend the knees slightly and place the hands just above the knees.
Keep your weight in the palms of your hands for the entire practice.
Focus your eyes on the abdominal area to help discern correct movements from incorrect movements.
There are three kinds of Nauli. They should be learned in the order of appearance here.
Madhima Nauli – central contraction
Technique:
Perform Uddiyana Bandha.
When the abdominal muscles are tight and the lungs are emptied of air, bring forward the central abdominal muscles (rectus abdominus) so that there is a kind of elongated bump in the center of the abdomen with concavities created on both sides.
Stay in this position as long as you can while holding your breathe.
Release Uddiyana Bandha.
Inhale deeply.
This is one cycle. In order to receive benefits from this practice you must start with 10 cycles, increasing the number gradually.
Vama Nauli and Dakshina Nauli – left contraction and right contraction (respectively)
(Note: You need to be very skilled with Madhima Nauli before you start Vama and Dakshina Nauli. A great deal of awareness and control of the abdominal muscles is required in order to distinguish between the contraction of the different muscles)
Perform Madhima Nauli
Slowly relax the right muscle. This action will cause the two muscles to shift to the left. You can make this easier by leaning forward and to the left. The left muscle must be as contracted as possible.
From here return to Uddiyana Bandha.
Gradually return your breathing back to normal.
Repeat on the other side.
One cycle of Nauli is complete after repeating Vama Nauli and Dakshina Nauli while holding the breath. The movement should look like a waving motion of the abdominal muscles. This movement is the source of the name Nauli. The speed and duration of the practice are determined by your physical ability.
One should only practice Nauli at least six hours after eating or defecating. The best time to practice this technique is before breakfast.