The object of prāṇāyāma practice is to emphasize the inhalation, the exhalation, or retention of the breath. Emphasis on the inhalation is called pūraka prāṇāyāma. Recaka prāṇāyāma refers to a form of prāṇāyāma in which the exhalation is lengthened while the inhalation remains free. Kumbhaka prāṇāyāma focuses on breath retention. In kumbhaka prāṇāyāma we hold the breath after inhalation, after exhalation, or after both.
