What a resting heart rate actually tells you

Resting heart rate is among the cheapest measurements in medicine, and among the most misread. Taken once, it says almost nothing. Tracked nightly, it becomes one of the better early signals we have.

What a rise actually means

An elevated resting rate over several nights indicates a system spending more than it is recovering. The cause might be training load, alcohol, illness arriving, or unresolved stress. The measurement flags the state without naming the cause.

Read alongside heart-rate variability and sleep architecture, the picture sharpens considerably. Together they tell us whether to push a protocol forward or hold it where it is for another fortnight.