Pranayama

Prāṇāyāma joins prāṇa, the vital life-force carried on the breath, with a second element read two ways: āyāma, 'extension' or 'lengthening,' or ā-yama, 'restraint.' So the word means either the lengthening of prāṇa or its conscious regulation — both senses are traditional and complementary.

As the fourth limb, prāṇāyāma is the deliberate regulation of the breath — its inhalation (pūraka), exhalation (recaka) and retention (kumbhaka). By working with the movement and the pauses of breath, the practice steadies the nervous system and, in yogic terms, gathers and directs prāṇa through the body.

Patañjali treats prāṇāyāma in the second chapter of the Yoga Sūtras, describing it as the regulation of the flow of inhalation and exhalation once a steady posture is established. The haṭha texts, notably the Haṭha Yoga Pradīpikā, develop the practice in far greater technical detail.

In practice, prāṇāyāma ranges from simply lengthening and evening the breath to structured techniques such as nāḍī śodhana (alternate-nostril breathing) or ujjāyī. It is usually learned after some steadiness in āsana, and traditionally under guidance, since forceful breath retention can unsettle body and mind.

Prāṇāyāma is not about breathing as hard or as much as possible. Its refinement lies in slowing, smoothing and lengthening the breath — often the retentions and the quiet pauses matter most. Aggressive forcing works against the very calm the practice is meant to cultivate.