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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

Urja's readiness score combines three signals that many people already collect:

• HRV vs your baseline — a variable wellness signal that Urja weights most heavily.
• Resting heart rate vs your baseline — a change can have many explanations, so Urja treats it as context rather than a diagnosis.
• Sleep — duration from Apple Health or Oura, scored against an eight-hour reference.

Everything else — steps, workouts, stress — is context, not the core score. For Apple-Health-derived scores, Urja starts with nominal weights of 45% HRV, 30% resting heart rate, and 25% sleep, then renormalizes across the inputs available that day. Wrist-temperature and daily stabilization may adjust the result. When Oura is connected, Urja uses Oura's readiness score directly — open Oura for its contributor breakdown. Tap Urja's ring to see the available components and adjustments.

Why "compared to you" is the whole game

An HRV of 45 ms can have different context for different people. That is why Urja compares your HRV and resting heart rate with your rolling baseline (sleep is scored against an eight-hour reference). The score summarizes how the available inputs compare with your recent pattern; it does not measure health or diagnose a condition.

How to actually use the number

Readiness is a decision aid, not a verdict. One cautious way to use it is:

• Well above baseline: consider your planned activity alongside how you feel, your training plan, and any symptoms.
• Around baseline: your usual plan may be reasonable if the rest of your context supports it.
• Well below baseline for one day: look for measurement changes and other context before reacting to one score.
• Below baseline for several days: consider reducing intensity and prioritizing recovery; discuss persistent symptoms or concerns with a qualified clinician.

Research comparing HRV-guided and predefined training suggests possible benefits in some groups and outcomes, but results vary by study design, population, and protocol. A readiness score should support—not replace—your judgment, training plan, and professional guidance.

Sources: Kiviniemi et al., 2010, daily HRV-guided exercise study; Düking et al., 2021, systematic review and meta-analysis.

Educational wellness information only — not a diagnosis or medical advice. Discuss lab results, supplements, and treatment changes with a qualified clinician. A readiness score is one input for planning your day, not a medical assessment.