What it measures — when you breathe slowly and evenly, your heart rate
naturally speeds up a little as you inhale and slows as you exhale. Coherence is how cleanly
that rise-and-fall formed one smooth wave, in time with the circle. The camera watches
your pulse and scores how much of your heart-rate movement sat in that single breathing rhythm
rather than wandering.
The number — 0 to 100. Near 0, your heart rate
drifted on its own, unrelated to your breath. Near 100, it rose and fell in one steady wave,
once per breath. The big number is your average across the session; peak is your
best stretch of it.
What it does NOT tell you — this scores
the exercise, not your health.
A high number means you paced your breathing well and your body settled into it.
A low one usually means the rhythm hadn't settled yet, you moved or talked, or the camera lost
your pulse — not that anything is wrong with your heart. It is not a
fitness test, and it cannot detect stress, anxiety or any medical condition.