How We Build Workouts

Every workout in The ERG Room is written by us from well-known training principles. Here is how we put them together, so you know what you are riding.

Power as a percentage of FTP

All targets are set as a percentage of your Functional Threshold Power (FTP), the highest power you can hold for about an hour. That makes one workout fit every rider: the files for Zwift and TrainerRoad scale to the FTP in your app, and the ERG file is calculated from the FTP you enter before downloading.

Zones

We use the classic seven-zone model built on FTP: active recovery (under 55%), endurance (56–75%), tempo (76–90%), threshold (91–105%), VO2max (106–120%), anaerobic capacity (121–150%) and neuromuscular power (above 150%). Charts are coloured by zone so you can see the purpose of a session before you start it.

Training stress and intensity

Each workout shows its duration, Intensity Factor (IF) and Training Stress Score (TSS). IF compares the normalized power of the session with your FTP; TSS combines intensity and duration, with one hour at FTP equal to 100. We calculate both from the interval structure, so your own numbers on the day will be close but not identical.

Testing

Before a workout is published we load its files into trainer software and ride or simulate it to check that targets, ramps and durations come through as intended.

Safety

Structured workouts are hard by design. Check with a doctor before starting intense training, especially after illness or a long break, and stop if you feel unwell. The workouts are general training sessions, not medical or individual coaching advice.