Athlete summary
A hard day (VO2, threshold, sweet spot, tempo, or race openers) is cleared only when your morning recovery signals look at least as good as your recent baseline — not because a single HRV number is green. If those signals are missing, Koyaro keeps the usual calendar spacing between hard days and does not invent a readiness score from one wearable reading.
Why single-signal HRV failed here
Alfonso, Clarke & Capdevila (Sci Rep 2025;15:34023): 28 experienced male cyclists, 31 days. Individual HIT was prescribed only when morning signals were at/above each rider’s baseline.
| Prescription rule | Power outcome |
|---|---|
| vmHRV-only | No significant power gains |
| vmHRV + wellbeing | Improved 1-min / 5-min |
| vmHRV + wellbeing + RHR | Largest gains (5-min 311→338 W; 20-min 261→285 W) |
RMSSD tracked RHR in ~82% of riders but did not track subjective markers (wellbeing significant in only 4/24). So HRV-only auto-prescription is the wrong default — it is a gate shape, not a new TSS / Banister load formula.
Caveats: n = 8–12/group after attrition; males only. We still cite the gate structure, not a universal effect size.
What the engine does
| Morning inputs | Gate |
|---|---|
| HRV + RHR + wellbeing (with baselines) | All three at/above baseline → allow quality; any below → demote to endurance |
| HRV + wellbeing (RHR missing) | Both must pass — minimum viable gate |
| HRV-only, RHR-only, WB-only, or nothing | Insufficient — no flip; keep spacing only |
| Altitude camp + wellbeing | Wellbeing is the tie-break; sea-level HRV/RHR must not red-light (Pirlot 2025) |
“At/above baseline” means:
- HRV — today’s rMSSD ≥ rolling geometric-mean baseline
- RHR — today’s resting HR ≤ baseline (not elevated)
- Wellbeing — today’s score ≥ individual baseline (1–5 typical)
Failed gate → downgrade VO2 / threshold / sweet-spot / tempo / openers to endurance. Easy / recovery days are untouched.
This composes after quality-day spacing and optional cycle-phase widening. Spacing decides when hard days land; this gate decides whether today’s hard day proceeds.
Form input when the roster is more than bike (— product rule, not new physiology): reuse this same gate for run and swim quality roles (including CSS tests). The form component shown is the sport of today’s planned quality session; if none, bike TSB stays primary. No Run Readiness / Swim Readiness mode.
Altitude caveat
Pirlot, Mihailovic, Gimenez, Millet, Brocherie et al. (Eur J Sport Sci 2025): elite female cyclists in LHTLH hypoxic rooms. Sleep can recover from ~day 5 while HRV stays altered through the middle acclimatization window (≥10 days). Do not use a sea-level HRV/RHR baseline to red-light quality days during an altitude camp — the autonomic shift is the environment. Wellbeing is the tie-break. Post-descent Hbmass decay is Altitude Hbmass decays in ~10 days — no in-season LHTH race watts.
Citations
| Key | Paper | Takeaway |
|---|---|---|
alfonso-2025-hrv-rhr-wellbeing | Alfonso C, Clarke DC, Capdevila L. Individual training prescribed by heart rate variability, heart rate and well-being scores in experienced cyclists. Sci Rep. 2025;15:34023. doi 10.1038/s41598-025-13540-z | vmHRV-only: no significant power gains; HRV+WB helped; HRV+WB+RHR largest gains. HIT only when signals ≥ baseline. |
pirlot-2025-altitude-hrv | Pirlot T, Mihailovic P, Gimenez P, Millet GP, Brocherie F, et al. Eur J Sport Sci. 2025. doi 10.1002/ejsc.12320 | During altitude camp, do not red-light quality days from sea-level HRV/RHR; sleep may recover while HRV stays off; wellbeing is the tie-break. |