Breathe Deeply... But How Deeply?

My yoga journey has taken me across studios, different cities, and countless instructors. One constant became a source of intrigue: the ubiquitous instruction to "breathe deeply." In dimly lit rooms filled with the scent of sandalwood, I'd contort into postures, the teacher's voice guiding us, "Inhale deeply, exhale completely." Yet, a silent question bloomed within me – what exactly constitutes "deep" breathing?

Imagine a roomful of bodies, each with a unique understanding of deep breaths. Some might puff up their chests, others might focus on their bellies rising. Did this fulfill the enigmatic "deeply"? Surely, a more precise approach could unlock a new dimension in my practice.