Bring the lab to the field.
Real-time DFA Alpha1, live metabolic zones, injury risk. All from your phone, during the workout.
€69.00/month · Includes every core feature · Cancel anytime
Your athletes train every day. You assess them once in a while.
In between, you have no data.
You do not know whether they are recovering.
You do not know whether the load is too much.
You do not know whether they get injured tomorrow.
Stress Index Sport changes everything.
Metabolic zones. No lab required.
The only parameter that tells you in real time which metabolic zone your athlete is in. No lab test. No CPET. Just a chest strap and a phone.
Pure aerobic zone
Active recovery, long endurance, aerobic base building.
Transition (above VT1)
Aerobic threshold crossed. Sustainable moderate load.
Anaerobic zone (above VT2)
Anaerobic threshold crossed. Intense effort, limited duration.
Maximal load
Maximum intensity. Sustainable for a few minutes only.
Updated every 5 seconds. Computed in a dedicated processor. Lab-grade precision.
Start a session. See everything in real time.
Start a sport session, connect the strap, and watch everything live:
- Live HR with scrolling chart
- Rolling RMSSD to monitor recovery
- DFA Alpha1 with the 4 color zones
- Tags during the activity (sprint start, pace change, break, end of warm-up)
- TRIMP computed automatically at the end of the session
Subjective + objective. The full picture.
At the end of every session, the app walks your athlete through a quick questionnaire:
Subjective data + objective HRV data = the full picture.
ln(RMSSD) with an individual baseline. The Plews method.
ln(RMSSD) trend with an individual baseline and normal band (Plews method). See at a glance whether your athlete is in shape, overtrained, or at risk.
Above the band
Recovered. Ready for a heavier load.
Inside the band
Normal. Planned load, no changes.
Below the band
Caution. Consider reducing the load.
ln(RMSSD), last 60 days
baseline 4.05 ± 0.30Normal band in teal. Green dots = recovery, red = caution.
Why Stress Index Sport. In one table.
| Feature | Kubios | HRV4Training | Stress Index |
|---|---|---|---|
| Real-time DFA Alpha1 | Desktop only | No | ✅ Mobile |
| Live metabolic zones | No | No | ✅ 4 zones |
| Muscle soreness map | No | No | ✅ 12 zones |
| Sport PDF report | Desktop, €750.00/year | No | ✅ Included |
| EU GDPR, servers in Europe | No | No | ✅ |
| Price | €750.00/year | €10.00/month, consumer | €69.00/month, Pro |
Coming next. For those who are in now.
The Sport Module is just the beginning. Here is what arrives in the coming months:
Professionals who activate now get early access to every new feature.
Bring the lab to the field. Activate the Pro plan.
€69.00/month · 60-day trial · Cancel anytime
Includes every Basic plan feature (€49.90/month) + the full Sport Module