HRV & Sleep Readiness Score

Blend HRV, last night’s sleep, and how beat-up you feel to decide if today is a go-hard, maintenance, or deload day. The score normalises against your rolling baseline so you can react before fatigue turns into overtraining.

Morning rMSSD or similar HRV metric from your wearable.
Use the same HRV metric as today’s reading for an apples-to-apples comparison.
Include total time asleep, excluding long wake periods.
Rate your current 7-day load or soreness on a 0–10 scale (10 = extremely fatigued).
Optional. Default 7.0/10 if left blank.

This score is not a substitute for medical advice. Consult a health professional if you notice persistent low readiness or symptoms of overtraining.

Examples

  • Today’s HRV 78 ms vs baseline 92 ms, slept 5.5 h, acute load 8/10, sleep quality left at default ⇒ Readiness score: 61.05% (HRV change -14.0 ms, ratio -15.22% vs baseline). Recommendation: Keep it moderate with session intensity ≈ 63.99% of your planned load (acute load 8/10).
  • Today’s HRV 102 ms vs baseline 95 ms, slept 8.0 h, acute load 4/10, sleep quality 8 ⇒ Readiness score: 85.73% (HRV change 7.0 ms, ratio 7.37% vs baseline). Recommendation: Go hard day with session intensity ≈ 90.02% of your planned load (acute load 4/10).

FAQ

What if my wearable uses SDNN instead of rMSSD?

Use the same metric consistently for both the daily reading and the baseline. The ratio normalises the units, so any HRV measure works as long as it is consistent.

How often should I update the baseline?

Rolling 30-day averages work well. If you are improving fitness rapidly, refresh the baseline every 2–4 weeks so the target keeps up with your adaptations.

What if my sleep is great but HRV tanks?

Solid sleep paired with a sudden HRV drop usually points to accumulated training stress or sickness onset. Dial back intensity for a day and layer in recovery (mobility, hydration, low-intensity walks).

Can I customise the weights on each component?

For a heavier focus on load, increase the acute-load value on the 0–10 scale before you calculate—this indirectly adjusts the weighting without changing the formula.

Additional Information

  • HRV ratio compares today’s reading with your 30-day rolling baseline to catch downward trends before they turn into overtraining or illness.
  • Sleep duration is capped between 4 and 9 hours for scoring so a single poor night does not tank the entire readiness index.
  • Acute load uses a simple 0–10 subjective scale; align it with your training log (e.g., session RPE × duration divided by chronic load).

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