Early in the morning before breakfast is the best time.
People who suffer from high blood pressure, heart problems, peptic or duodenal ulcers, colitis and other serious abdominal problems should not do this practice. Pregnant women should not do this practice, though they can perform it after childbirth to strengthen the abdominal muscles and reshape the abdominal area in general.
The stomach must be empty before attempting this practice. Wait for four to five hours after eating your meal. If possible try to evacuate the bowels before doing the practice.
The benefits are almost the same as for jalandhara bandha. The entire abdomen is squeezed like a sponge. This pushes out all the stagnant blood. All the inner organs are revitalized. It can help to alleviate or prevent a large number of abdominal ailments including indigestion, constipation, diabetes, colitis and so forth if they are not too serious and chronic.
The adrenal glands are regularized thereby giving energy to a lethargic person and relaxation to an anxious or overwrought person. The solar plexus is also normalized. This centre is sometimes called the abdominal brain and it is the centre of energy in the whole body. This centre directs the correct flow of energy to all the different organs.
Uddivana bandha normalizes this centre and thereby helps to regulate the energy level in the whole body.
In the final position the air in the lungs is pressurized by the upward movement of the diaphragm and the false inhalation. This helps to open out the alveoli in the lungs and improves lung efficiency. At the same time the heart is given a good massage, which improves its functional efficiency.
Uddiyana bandha also has many subtle influences on the pranic body. The navel is the area of the manipura chakra, which is the centre of prana in the body. Physical stimulation of this area has repercussions on the more subtle flows of prana and its distribution throughout the body. Uddiyana also redirects prana into the sushumna nadi. This helps to expand awareness and induces meditation.
Uddiyana bandha can also be done in a standing position. This is generally easier for beginners. The technique is as follows: Stand with your feet about half a meter apart. Bend forwards and bend the legs slightly at the knees. Place your palms on the knees. Exhale deeply; try to empty the lungs as much as possible. Then bend your head downwards and press the chin against your chest in jalandhara bandha. Make sure your arms are straight. Then make a false inhalation (expand the chest as though breathing in, but not actually taking in air). Straighten the legs slightly. This movement will automatically draw the abdomen upwards and inwards to form uddiyana bandha. Hold this position for a comfortable length of time. Then release the expansion of the chest and bend the legs, release jalandhara bandha and finally breathe in.
This method gives basically the same benefits as uddiyana bandha performed in a sitting position. However, the sitting form is preferable because it is more suitable for combination with meditative and pranayama practices.