Ride Fatigue Resistance
Ride Fatigue Resistance shows how much of your normal cycling power you can still produce after you have already done a lot of work in a ride. It measures durability, not tiredness on the day. For daily readiness, use the Overview and Wellness.
Set it up in Intervals.icu
Montis reads the fatigued power curves that Intervals.icu works out for you. You set these up once.
- In Intervals.icu, open your Power settings and find Power Curves.
- Add one or two fatigued curves by entering a kJ value for each one, for example 1000 kJ and 2000 kJ. These numbers are only an example. Choose values that suit your longer rides.
- Ride as normal. A fatigued curve only fills in once your rides go past that amount of work.
Montis then picks the curves up by itself. You do not need to change anything in Montis.
- It covers rides with power only (outdoor and virtual). Runs and other sports do not get it.
- Until fatigued curves exist, the app shows a short setup hint where the panel would be. Learn more opens this page.
How it works
- Montis compares your last 85 days with the 85 days before that. The window ends on the report end date, not on today.
- For each duration (5 s, 1 min, 5 min, 20 min and 60 min) it divides your fatigued power by your normal power from the same 85 days. That gives retention %.
- The durations are grouped into four power areas: Short Power (5 s and 1 min), VO2 (5 min), Threshold (20 min) and Long Duration (60 min).
- Overall retention is the middle value of those four areas, not a plain average.
- If you set up two curves, the summary uses the higher kJ value that also has data in the earlier window.
Reading the panel
| Item | What it shows |
|---|---|
| State | Robust (overall retention 90% or more), Moderate (80% or more) or Limited (below 80%). Unknown when fewer than three power areas have data. |
| Trend | Improving or Declining when retention moved by at least 2 pp since the earlier window, otherwise Stable. Baseline when there is no earlier curve to compare with. |
| Confidence | High, Moderate or Low: how sure Montis is of the result. |
| After … kJ | Which of your fatigued curves the summary uses. |
| Primary Limiter | The power area that holds up least well, for example Long Duration. |
| Retention % | Current and previous overall retention, and the change in percentage points (pp). |
Where you see it
- Montis App: the adaptation card on the Overview, the energy system cards on Micro (Weekly), the season view on Meso (Season), and section 2 of the Coaching Workflow. The weekly workflow email adds one Ride Fatigue Resistance line when the report has it.
- ChatGPT & Claude: the Weekly and Season reports show one summary row per kJ curve. The short weekly overview may not mention it.
- It is not part of Macro (Summary) or the Summary report.
How to read it
- Read it next to your fresh power, not instead of it. You can get fitter when fresh but less durable, or the other way round.
- The numbers come from the Montis engine. The AI Coach explains them and is told not to recalculate them.
- It is evidence for coaching only. It does not change the Adaptive Decision Engine score or directive.
More: Energy System Progression (ESPE) · Adaptive Decision Engine (ADE)