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What readiness really means

4 min read

"Readiness," "recovery," "body battery" — every wearable has a number, and most never tell you what is inside it. Here is the honest version.

The three ingredients that matter

A trustworthy readiness score is built from a small number of well-validated signals:

• HRV vs your baseline — the strongest single indicator of autonomic recovery. Weighted most heavily.
• Resting heart rate vs your baseline — a rise of even 5 bpm above your norm is a classic early sign of under-recovery or illness.
• Sleep — duration and, where available, stages. No amount of good HRV compensates for chronic short sleep.

Everything else — steps, workouts, stress — is context, not the core score. Urja weights HRV at 45%, resting heart rate at 30%, and sleep at 25%, and it will show you the exact breakdown when you tap the ring. No black box.

Why "compared to you" is the whole game

An HRV of 45 ms might be excellent for one person and poor for another. Population averages are almost meaningless at the individual level. That is why Urja compares today only to your rolling baseline. The number answers one question: are you more or less recovered than your normal?

How to actually use the number

Readiness is a decision aid, not a verdict. The evidence-based way to use it:

• Well above baseline: your body is primed — a good day for intensity or a personal-best attempt.
• Around baseline: train as planned.
• Well below baseline for one day: normal noise — do not overreact.
• Below baseline for several days running: this is the real signal. Pull back, prioritise sleep, and let your body catch up.

Athletes who train guided by HRV in this way have shown greater fitness gains than those following fixed plans (Kiviniemi et al., European Journal of Applied Physiology, 2010). The point is not to chase a high number — it is to stop training hard on the days your body is asking for a break.