TSB (Training Stress Balance)

TSB is CTL minus ATL — your 'form.' Positive TSB means you're fresher than your training has been lately (rested, primed for a race); negative TSB means you've got fatigue debt (mid-training block, overreached, or undertrained the taper). The zero line isn't magic — context matters.

TSB = CTL − ATL

Rough heuristics: TSB > +10 typically means taper/race ready; 0 to −10 is maintenance; −10 to −30 is heavy training; below −30 is overreach territory (useful briefly, risky long-term). These are directional, not prescriptive.

Peaking for a race is the process of pulling TSB from deeply negative during the build phase up to approximately +5 to +15 on race day while preserving as much CTL as possible. That's what tapers do mathematically.