When to Back Off Training? What HRV, Resting Heart Rate and TSB Are Telling You
The plan says "threshold today", but your body says otherwise. Instead of guessing, you can check in two minutes in the morning: three signals — HRV, resting heart rate and TSB — together give a fairly clear answer to whether today should be a hard ride, an easy one, or a day off entirely.
Three signals, not one
None of these indicators is reliable on its own. Only together do they build a picture you can trust.
HRV (heart-rate variability)
Measured in the morning, lying down, ideally with the same device at the same time. A single drop means nothing — the body has natural day-to-day variability. What matters is the trend over several days: a clear, sustained drop below your own baseline is a sign of insufficient recovery.
Resting heart rate
A simpler and cheaper signal than HRV — no dedicated sensor needed, a watch or even a manual morning check will do. A rise of 5–8 beats per minute above your own average is a common early sign of fatigue, infection or lack of sleep.
TSB (Training Stress Balance)
Unlike HRV and heart rate, TSB says nothing about your physiological state on a given day — it shows how much accumulated training load you're carrying. A heavily negative TSB (below -20/-25) means your body has been running on credit for a while. More on this indicator and how to read it alongside your load chart in our article on load tracking for amateurs.
How to read them together
| HRV | Resting heart rate | TSB | Decision |
|---|---|---|---|
| Normal | Normal | Normal or slightly negative | Ride as planned |
| Normal | Normal | Heavily negative | Ride, but consider a lighter session |
| Lowered | Raised | Any | Back off or ride very easy (Zone 1–2) |
| Lowered | Normal | Normal | Watch it — could be one off day, not a trend |
| Normal | Raised | Any | Check whether you're coming down with something — back off |
When one bad signal is enough to back off
If your resting heart rate is clearly raised (not 1–2 beats, but 5+), that alone is reason enough to swap the plan for an easy day or a full day off — regardless of what HRV or TSB show. It's the fastest, most unambiguous sign of infection or serious under-recovery.
What this doesn't replace
This is a tool for the daily "ride hard today or not" decision, not a diagnosis. If the signals have been off for a week, not a day, it's no longer a matter of one easy session — it's worth reading how to recognise and climb out of overtraining before it turns into a longer slump.
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