Having achieved this [āsana], prāṇāyāma is the regulation of the movement of inhalation and exhalation.

Tasmin sati: “having achieved this.” Prāṇāyāma is practiced after establishing āsana. The order is not arbitrary.

Śvāsa is inhalation; praśvāsa is exhalation. Gati-viccheda is the interruption or regulation of their movement.

Prāṇāyāma is not simply breathing; it is the control of prāṇa, the vital energy that moves with the breath.

At its simplest level, prāṇāyāma is making the unconscious conscious: observing and regulating the respiratory rhythm.

At advanced levels, it involves retentions (kumbhaka) and the direction of prāṇa through the subtle channels (nāḍīs).

Breath is the bridge between body and mind; controlling it is to gain access to both.