Neverpedia
Training load
TSB (Training Stress Balance)
CTL minus ATL — a single number that estimates how fresh or fatigued you are.
Training Stress Balance (TSB) is simply CTL minus ATL. It is the freshness number.
How it is calculated
TSB = CTL_yesterday - ATL_yesterday
(Using yesterday's values is the standard PMC convention.)
Why it matters
TSB summarizes whether you are stacking fatigue or shedding it.
- TSB ≤ -25: Deeply buried. Sustainable for short build blocks only.
- TSB -15 to -5: Productive overload. Where most training lives.
- TSB -5 to +5: Steady state.
- TSB +5 to +15: Fresh — race window.
- TSB > +20: Rested but possibly detraining.
Common misconceptions
- Positive TSB is not always good. Long stretches above +15 mean you are losing fitness.
- A bad race day with positive TSB does not mean the model is broken — fitness, durability, and execution all matter beyond TSB.
- TSB does not predict feel on any single day. Use it as a guide, not a verdict.
Related concepts
CTL, ATL, TSS.