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Why a single metric misses the picture

HRV alone is noisy. Sleep alone tells you nothing about training stress carried over. Resting heart rate moves slowly. A wearable picking one of these and calling it your "recovery" is making a confident-looking guess off partial data. The athletes who consistently train well combine signals.

How the score is built

You enter six inputs and the calculator weights them like this:

  • Sleep duration and quality: 25%
  • HRV: 20%
  • Resting HR: 15%
  • Perceived stress: 15%
  • Yesterday's TSS: 15%
  • Training load trend: 10%

Each factor is scored against physiological reference ranges, then combined into a 1 to 10 score. 8 to 10 means go hard, 6 to 7 means train as planned, 4 to 5 means easy day, 1 to 3 means rest.

If you don't have a wearable

Enter 60 ms as a baseline HRV. The other five factors carry enough signal for a useful score. The accuracy gap versus Whoop or Oura is mostly automation, not the underlying logic. A 60-second self-check at the same time each morning is more consistent than people expect.

AI-Enhanced

Recovery & Readiness Score

Enter your morning metrics and get a go/no-go recommendation for today's training. This composite score weighs multiple factors. Something no single metric can do alone.

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FAQ

What is HRV and why does it matter?

Heart Rate Variability measures the variation in time between heartbeats. Higher HRV generally indicates better recovery and parasympathetic (rest-and-digest) dominance. It's one of the best single biomarkers for recovery status.

I don't have an HRV monitor — what should I enter?

Enter 60ms as a baseline estimate. The calculator weights all six factors, so even without precise HRV data, sleep quality, resting HR, and perceived stress still produce a useful readiness score.

How accurate is this compared to Whoop or Oura?

This uses the same underlying principles (HRV, sleep, training load) but with self-reported data. Wearables provide continuous automated measurement which reduces user error. Think of this as a structured self-check when you don't have a wearable.

Methodology

Weighted composite scoring: Sleep (25%), HRV (20%), Resting HR (15%), Perceived Stress (15%), Yesterday's TSS (15%), Training Load Trend (10%). Each factor is scored 1-10 using physiological reference ranges, then combined. Score 8-10 = go hard, 6-7 = normal, 4-5 = easy, 1-3 = rest.

Want to verify the math?

Explore 170+ reference calculators built by engineer-athlete Thomas Prommer. The technical foundation behind our AI.

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