The bandhas are known as the body’s locks. They are made from muscle but are not used to help the body move, rather playing a supportive role. They are used in yoga because they help to bring energy up the body. There are four:

Mulbhand: the root lock, is part of the pelvic floor musculature. To engage this lock you pull in the muscles around the perineum. Any time that you are intensively bending your torso, it’s a good idea to lightly engage the Mulbhand to support your spine.

Uddhyana: the diaphragm lock. Is activated when you contract your abdomen and draw it upwards.

Jalandhara: the neck lock, elevates the neck vertebra. Engage this lock by pulling in your chin, while at the same time pulling up the top of your head.

Maha Band: the great lock, is engaged by using all three together, while at the same time bringing your tongue backwards and pressing it into your soft pallet, and also closing your eyes and rolling the eyeballs upwards.