Pattern timings
Each pattern is a fixed sequence of phases. Box breathing repeats inhale 4 s, hold 4 s, exhale 4 s, hold 4 s - a 16-second round. The 4-7-8 technique repeats inhale 4 s, hold 7 s, exhale 8 s - 19 seconds per breath. Wim Hof breathing runs roughly 30 rapid breaths followed by a breath hold after the final exhale, repeated in rounds. The tool advances through the phases of the pattern you chose.