Bandhas are internal muscular holds used to generate heat and focus energy in three parts of the body. They are primarily used during pranayama (yogic breathing) practice, although they can be performed during yoga poses (asanas) as well.
There are three types of bandhas, and they should be practiced in this order: Mula Bandha (Root Lock), Uddiyana Bandha (Abdomen Lock) and Jhalandara Bandha (Throat Lock).
Mula Bandha
In its crudest form, the root lock seems to be just a fancy term for clenching your butt. Actually, it is much more subtle than that and has a supporting effect throughout the body.
To perform mula bandha, exhale and access your pelvic floor, the space between your pubic bone and tailbone. Gently pull it upward toward your belly button.
At first you may need to simply contract and hold the muscles around your anus or genitals or both until you get a feel for things down there. However, what you really what to focus on and lift is the perineum, that ticklish spot between your anus and genitals.
While holding the lock, do not hold your breath. Breathe naturally. Engaging mula bandha while doing yoga poses adds to the concentration and the integrity of the poses.
Uddiyana Bandha
To perform the abdominal lock, sit in a comfortable cross legged, half- or full-lotus position. Exhale completely. Then draw the abdomen in and up without inhaling. Use your intracoastals to press your abdomen from the sides. Draw everything up and underneath the rib cage. To unlock, relax the abdomen and inhale. Repeat often.
As with the mula bandha, the uddiyana bandha can also be used during yoga poses. In order to do this while not succumbing to shallow lung-centric breaths, you must access the diaphram.
While holding the lock, expand the diaphram during inhalation. This will fill the lungs from top to bottom. If you can see the diaphram push out below your sternum, you are doing it correctly. You will also feel pressure throughout the abdomen with each breath. This is a good thing. The bandha naturally massages and cleans the abdominal organs, and the gentle pressure from the breath intensifies this therapy.
Because of the contracting and lifting movements in both the mula and uddiyana bandhas, they are complimentary and should be attempted together if possible. Lifting and contracting the pelvic floor facilitates doing the same with the abdomen. Combining these locks while practicing yoga asanas is exceptionally beneficial.
Jalandara Bandha
To do the throat lock, sit, as before, in a comfortable cross legged, half- or full-lotus position. Partially inhale, and then hold your breath.
Drop your chin about halfway to your chest. The pull your chin back toward your chest so that your neck is in line with your spine, not rounded. Hold your breath as long as you comfortably can. You will feel the lock high in your throat and along your neck almost in to your scalp. This bandha contributes to correct posture and is believed to take pressure off the heart and lungs.
Of the three, this is the most difficult bandha to precisely acheive. Serious practicioners should consult a teacher well-versed in yogic breathing techniques.
Performing all three locks at once -- the mula, the uddiyana and then the jalandara -- creates what is called the Mahabandha, the Great Lock, which is said to renew nerves and glands as well has lower blood pressure.
The bandhas can be performed anywhere, while sitting in traffic, balancing your checkbook or hunting for pipe-links. They can be done together, separately or integrated in to asanas.