From LSWiki

Class: Athletic Skills
Attribute: Vitality
Pedagogy: Physical Training
Practitioner Term: Practitioner of Breath Control

The practiced ability to regulate one's breathing for the best results in various situations.  Those skilled at breath control have
greater endurance and, naturally, can hold their breath quite a bit longer.

Trainers

Trainers: 
Wandering Lhethan Hagal
Association required:
Agnihotri: Riga
Obsidia: Goth
Guild required:
Aligned: Taiji
Aisenshi: Musashi
Hawkmen: Shayera
Ordo Ignis Aeternis: Iklam Wanders
Quest required