TSS Calculator
Score a ride's Training Stress from its duration, normalized power and your FTP.
What it means
Training Stress Score (TSS) puts a single number on how much a ride took out of you, combining how long you rode with how hard. An hour flat-out at threshold is defined as 100 TSS.
It's built from Intensity Factor (IF) — your normalized power divided by FTP — squared, times duration in hours, times 100. Tracking weekly TSS is how you manage progressive overload without digging yourself into a hole.
Common questions
Very individual — recreational riders often sit around 300–500/week, while committed racers push 700–1000+. What matters is progressing gradually from your own baseline.
Ride & Run Lab calculates all of this automatically from your real rides — plus an AI coach, form & fitness tracking and segments. $5/month.