Fitness Simulator

Simulate your fitness build over weeks — plan your season with real numbers.

Configure Simulation

Weekly Load
Fitness Curve over Simulation Period
Weekly Breakdown
WeekLoadFitness (end)ChangeLoad Zone

Track Real Fitness from Strava

WattRun calculates your fitness automatically from your activities — updated daily with fatigue and form.

Start for free →

Free · No subscription

What now?

You now know your number. What do you do with it?

Data is free — the daily decision isn't. WattRun builds a plan around your number, fits it to your real week and tells you what to do today — with a reason, not just charts.

For cycling and running · tell us in 15 seconds how you feel