Chin Lock: Jalandhar Bandh  # 1 Lock

The chin is to be pressed on the chest after contracting the throat. This bandha eliminates old age and death. The contracted veins in the throat ensure that the liquid from the skies is received here. Hence, the bandha has been appropriately known as Jalandhar Bandha, which means that it destroys any pain in the throat.

It stimulates the Thyroid gland and the nerves in the neck along the spine

Upward Abdominal Lock: Uddiyana Bandha # 2 Lock

Strengthens the abdominal muscles and diaphragm.

Massages abdominal viscera, the solar plexus, and the heart and lungs.

Increases gastric fire; improves digestion, assimilation, and elimination; and purifies the digestive tract of toxins.

Stimulates blood circulation in the abdomen and blood flow to the brain.

While sitting lift the stomach  towards the chest and keep it there for at least  10 secs.

Root Lock : Mula Bandha # 3 Lock.

The root lock, or Mula Bandha, is a posture where the body from the anus to the navel is contracted and lifted up and towards the spine.  It is a technique used not only in asana practice, but in pranayama and meditation as well

This chakra provides a sense of grounding, stability and security. As the lowest chakra, a balanced muladhara is the foundation for activating the rest of the chakras. Mula bandha improves flexibility, tones the digestive and reproductive organs and boost sexual energy.

While sitting lift the anus upwards and keep it up for at least 10 secs.

Maha Bandha : All locks together at the same time:

While sitting do all the locks simultaneously. Expel all air from the lungs then

start with Root Lock followed by Upward Abdominal Lock and finally a chin lock.

Stay is this state for at least  30 secs

Important Note:

The exercise routine which follows will use these locks as part of the process.