Hi, I'm Matthias. I live on the outskirts of Berlin, I've been running for a number of years, and I ride a road bike. By day I'm a software developer.
I've run quite a few half marathons and marathons. My best times are 1:36 for the half and 3:19 for the full. Most of what I know about pacing I learned in races, sometimes the hard way.
On the bike, I like long days in the mountains best. I've ridden the Ötztaler Radmarathon in the Austrian Alps twice: 227 km, about 5,500 m of climbing, four passes. In 2021 it took me 11 hours 37 minutes, and I named the ride "Hart, härter, Ötztaler Radmarathon" on Strava (hard, harder, Ötztaler). A year later I was an hour and a half faster, mostly because I still had legs for the last climb and spent less time at the aid stations.
One thing kept bugging me in training: my watch and bike computer gave me plenty of numbers, but never told me what they meant or what to do tomorrow. Being a developer, I eventually just built the tools for that myself.
That became WattRun, an AI training coach for cyclists and runners. The free calculators on this site came out of that work.
How this site works
The calculators here are based on published, well-tested methods:
- Coggan/Allen power and heart-rate zones: FTP-based training zones.Source: Hunter Allen & Andrew Coggan, Training and Racing with a Power Meter
- Joe Friel's threshold heart-rate (LTHR) field test: heart-rate zones from a 30-minute solo effort.Source: Joe Friel, The Cyclist's Training Bible
- Tanaka's maximum heart-rate estimate: 208 minus 0.7 × age, used only when no measured value is available.Source: Tanaka, Monahan & Seals, “Age-predicted maximal heart rate revisited”, Journal of the American College of Cardiology (2001)
- Banister's fitness-fatigue model: Fitness, Fatigue and Form as rolling 42- and 7-day averages of training load.Source: Banister et al., “A systems model of training for athletic performance”, Australian Journal of Sports Medicine (1975)
- The physics of road-cycling power: speed from watts, weight, rolling resistance, air drag and gradient.Source: Martin et al., “Validation of a Mathematical Model for Road Cycling Power”, Journal of Applied Biomechanics (1998)
I use AI to help me draft and structure articles. I check the numbers myself, redo the calculations and read every page before it goes live. Each article shows when I last reviewed it.
Questions and corrections
Found an error or have a question? Email me at hallo@wattrun.de.
If you want this kind of explanation for your own training, WattRun reads your rides and runs and tells you what to do today and why.
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