A ZWO file is a structured workout file format used primarily by Zwift. It defines interval-based training sessions for cycling and running, specifying targets like power, cadence, duration, and rest periods.
ZWO files do not store activity results; instead, they describe how a workout should be performed.
What data does a ZWO file contain?
ZWO files can include:
- Interval durations
- Target power (watts or FTP percentage)
- Cadence targets
- Rest and recovery blocks
- Warm-up and cool-down segments
- Basic workout metadata
ZWO files focus entirely on workout structure rather than performance data.
Where are ZWO files commonly used?
ZWO files are most commonly used within Zwift, where they power custom and imported structured workouts.
You may also encounter ZWO files when exporting or sharing workouts from TrainingPeaks, coaching platforms, or online workout libraries, as ZWO is a popular format for distributing structured training plans that can be loaded directly into Zwift.
When should you use a ZWO file?
ZWO files are best when you:
- Create or follow structured interval workouts in Zwift
- Share training plans with coaches or teammates
- Reuse workouts across indoor training sessions
- Focus on planned training rather than recorded activity data
Limitations of ZWO files
ZWO files have important limitations:
- No GPS, heart rate, or activity result data
- Not suitable for recording completed workouts
- Limited compatibility outside of Zwift-style platforms
ZWO files are meant for planning workouts, not analyzing performance.
Converting ZWO files
With FitConvert, you can convert ZWO files into formats like FIT or TCX so structured workouts can be used across a wider range of fitness devices and training platforms.