Patañjali's Yogasūtra I.34

Yogasūtra I.34 - pracchardana-vidhāraṇābhyāṁ vā prāṇasya

When we find interruptions or the system of interruptions,

The practice of breath regulation, involving the extension of exhalation and retention after exhalation might be helpful.

However, these breathing techniques must be correctly learnt under the guidance of a competent teacher, who has the knowledge and experience to guide us.