Exploring Prāṇāyāma as Prāṇāyāma within
Śikṣaṇa Krama requires a mastery of the inhale.
For that using Viloma Ujjāyī is recommended.
It is a short-term technique taught specifically
to develop and refine the inhale as a preparation
for working with long-term bi-channel techniques
such as with Nāḍī Śodhana and Sūrya Bhedana.