What’s a good TSB for racing?
Training Stress Balance (TSB) is a simple way to gauge how fresh you’ll feel on race day. It blends your recent fatigue with your long-term fitness to estimate “form.” Hit the right range and you’re sharp. Miss it and you’re either dull from fatigue or too flat from over-resting.
This guide explains realistic race-day TSB targets and how to taper to land them, without losing hard-earned fitness.
What TSB actually measures
In most platforms, TSB is calculated from two rolling loads:
- CTL (chronic training load) ≈ long-term fitness, usually a 42-day time constant.
- ATL (acute training load) ≈ recent fatigue, usually a 7-day time constant.
TSB = CTL - ATL (often called “Form” or “Freshness”)- Negative TSB (e.g., -10 to -30): you’re carrying fatigue. Useful in heavy training blocks.
- Near zero (e.g., -5 to +5): balanced—often OK for training or the start of a stage race.
- Positive (e.g., +5 to +25): fresher and sharper for a one-day race or key time trial.
Important nuances:
- Different platforms may use slightly different time constants. The concept still holds: lower recent load relative to your base = higher TSB.
- TSB is only as accurate as your FTP and TSS. If FTP is set too low/high, CTL/ATL/TSB are skewed. Keep FTP current with recent tests or power PRs.
- TSB complements, not replaces, readiness signals like sleep, HRV, mood, and how you feel in warm-ups.
Rule of thumb: train negative, race positive.
Race-day targets by event and rider
There’s no universal “best” number, but these ranges cover what most ambitious amateurs find works. Start here, then personalize.
| Event type | Typical race-day TSB | Notes |
|---|---|---|
| Criterium / cyclocross (30–60 min) | +10 to +25 | Explosive efforts benefit from freshness. Too high (>+25) can feel flat—include sharp openers. |
| Time trial (20–60 min) | +10 to +20 | Keep snap without losing threshold feel. Most ride best near +12 to +18. |
| Road race (90–180 min) | +5 to +15 | Balance freshness and endurance. Many target around +8 to +12. |
| Gran fondo / long mountain day (4–8 h) | 0 to +10 | Too much taper risks losing endurance feel. Aim small positive, start controlled. |
| Stage race (start of multi-day) | 0 to +10 | Arrive fresh but not over-rested; you’ll build fatigue across stages. |
Individual adjustments:
- Masters athletes often prefer a bit more positive TSB for one-day races (+12 to +20).
- High-volume riders with big CTL may not need very high TSB; they carry fitness well.
- Lower-volume riders may need a slightly higher TSB to feel sharp, but avoid big drops in volume that lead to flat legs.
Tapering to land your target TSB
Tapers aim to lower ATL while protecting CTL. Keep intensity touches, reduce volume, and arrive feeling snappy.
How much and how long to reduce
- Duration: 7–14 days for most events; shorter (5–7 days) for punchy races, longer (10–14) before very long events.
- Volume: reduce weekly TSS by ~30–60% compared with your final build week.
- Intensity: keep 2 quality sessions per week at race-relevant power (threshold/VO2max/sprints). Cut the number of reps, not the targets.
Practical weekly outlines:
- Criterium/cross (5–7 day taper): 35–45% volume reduction; 2 sharp sessions with 30 s–3 min work at 110–130% FTP; frequent but short strides/sprints.
- Time trial or 2–3 h road race (7–10 days): 40–50% volume reduction; 1 session with 2×8–12 min at 100–105% FTP, 1 VO2 set (e.g., 4×3 min at 115–120%); endurance filler.
- Gran fondo/long climbs (10–14 days): 40–60% volume reduction; early-week sweet spot (e.g., 3×10 min at 88–94% FTP), one short race-pace session, more Z2 to keep endurance feel.
Openers and the final 48 hours
- 48 hours out: easy Z2 with a few 20–30 s spins at 120–140% FTP to wake up.
- 24 hours out: a short opener ride—example: 20–30 min easy, then 3×1 min at 115–125% FTP (2–3 min easy between) + 3–5 short sprints; cool down.
- Race morning: brief activation if needed (5–10 min ramp + 2–3 short efforts).
Worked example
Say your current CTL is 80 and ATL is 90, so TSB is -10. You’re targeting +10 for a TT in 10 days. You want ATL to drop to ~70 while keeping CTL stable.
- Reduce next week’s TSS by ~40–50% vs. your last heavy week.
- Keep 2 intensity sessions (reduced reps) and otherwise ride easy.
- By day 7–10, ATL typically falls enough to push TSB from -10 to around +5 to +15 for most riders.
Don’t chase an exact number day by day. Nudge the trend and verify with how you feel in openers.
Readiness checks to confirm TSB
- Subjective feel: legs pop in warm-ups, mood is good, no heaviness climbing stairs.
- Sleep and resting HR: normal or better-than-average.
- HRV or similar readiness: near your baseline, not suppressed.
- Power in openers: you can hit targets without strain; RPE aligns with watts.
Common pitfalls and quick fixes
- Over-tapering (TSB > +25): add a short opener day and a bit of Z2 to regain “feel.”
- Under-tapering (TSB still negative): take an extra rest day, trim endurance rides, keep one sharp session.
- FTP set wrong: update before the taper if you’ve had clear gains or losses; otherwise, don’t move the goalposts in race week.
- Last-minute CTL chase: you can’t build meaningful fitness in the final 10 days. Protect freshness instead.
Use TSB as a compass, not a ruler. Aim for the ranges above, confirm with simple readiness checks, and keep just enough intensity in your taper so your watts—and your confidence—show up on the line.
