Having filled to the cavity of the throat, retaining firmly with the bandhas applied with effort, one should practice kumbhaka of sixteen units, and then exhale in thirty-two.

This verse introduces the specific proportions for prāṇāyāma practice. The inhalation fills the lungs completely “to the cavity of the throat” (ākaṇṭhakūpāt), indicating a complete and deep breath.

The retention must be done bandhayutam (with the bandhas applied) and sthiram (firmly). The three principal bandhas — jālandhara, uḍḍīyāna, and mūla bandha — are applied during kumbhaka to seal the prāṇa and direct it toward suṣumnā.

The proportions mentioned are 16 for kumbhaka and 32 for rechaka (exhalation). Together with the implied pūraka, this suggests a ratio where the exhalation is double the kumbhaka. These measures are counted in mātrās (time units), traditionally measured by the time of a finger snap or a mental recitation of a short mantra.