Sweaty Hat - Breath Coach

Guided breath training, a proper BOLT test, and a Progress screen that shows whether your easy runs are getting cheaper. Nothing leaves your phone.

Breath Coach is a coaching and tracking tool for breath training — built by a runner to test one question honestly: can training the breath make running at your existing fitness feel easier?

Guided sessions. Pick a goal and follow the bubble, the spoken cues, or the taps on your wrist — eyes closed if you like.

Energize — fast breaths, then breath holds, three rounds. Alert and buzzing. Slow, regular or fast pace. CO₂ Tolerance — breathe a little less than you want to. The practice that raises your BOLT score. Calm, Focus, Meditate, Sleep — breath-only, no holds, from three to eight minutes. Custom — your own timings.

BOLT test. A comfortable breath hold after a normal exhale, timed for you, with clear instructions so you take it the same way every morning. The score tracks how tolerant you are of carbon dioxide — the thing that actually makes you feel out of breath. Waking scores trend over weeks; the band ("developing", "solid", "strong") is a rough label, the direction is the signal.

Progress. The N=1 view. Alongside BOLT, the app reads your easy runs from Health and shows beats per km (pace-normalised heart-rate cost) and cardiac drift (how much heart rate climbs to hold the same pace). Add a 1–10 breathing-effort rating after each run. A 12-week block with a baseline week and checkpoints at weeks 4, 8 and 12 makes the comparison fair. Export everything as CSV.

Apple Watch. Full sessions on the wrist, standalone or mirrored from the phone. Live heart rate, heart rate at the end of every hold, distinct inhale/exhale taps, an always-on view for when your wrist drops mid-hold, and a BOLT test on the watch.

Everywhere else. Live Activity on the Lock Screen and Dynamic Island. Home-screen Quick Start widget. Siri, Shortcuts and Action button support. Ambient sounds. Spoken cues.

Private by design. Nothing leaves your device. No account, no analytics, no tracking. Sessions are written to Health as Mind & Body workouts; run data is read from Health only when you ask.

Breath Coach is a coaching and tracking tool, not a medical device. Never practise breath holds in or near water, while driving, or if you're pregnant or have a heart, blood-pressure or respiratory condition without medical advice. Stop if you feel dizzy.