Uddiyana Bandha — a Hatha Yoga technique — is an “abdominal lock” popularly referred to as the “upward flying lock.”
This Bandha, which can be done standing or sitting down, is commonly performed in conjunction with two other Bandhas, that is, the Mula Bandha and Jalandhara Bandha. The three Bandhas then are joined together in the Maha Mudra exercise.
In the Maha Mudra practice (sometimes also referred to as Maha Bandha practice), Uddiyana Bandha typically follows after doing Mula Bandha and before doing Jalandhara Bandha. Nevertheless, Uddiyana Bandha can also be carried out separately.
Uddiyana is an exercise in which you deliberately draw the abdominal area i.e. diaphragm in and upwards at the end of a full exhale, while you hold your breath at the top of the retraction. This is called an abdominal lift, or alternatively a diaphragmatic lift.
In fact, the exercise moves the internal organs in a higher position in the abdominal cavity, which is thought to massage, tone, strengthen, and cleanse the abdominal organs and deep internal muscles, additionally stimulate our life energy and blood flow, while releasing tension and stress.