Tcx

TCX, in the most common use within fitness and activity tracking, stands for Training Center XML. It is an XML-based data interchange format developed by Garmin for exporting and sharing workout data. TCX files typically use the .tcx extension and are used by Garmin devices and related software to record activities such as runs, rides, and swims.

A TCX file stores one or more activities, each containing laps and tracks. A track consists of trackpoints, each with a timestamp and data fields such as geographic position (latitude/longitude), altitude, distance in meters, and optional metrics like heart rate, cadence, and speed or pace. The format supports extensions for device-specific data, such as power or other sensor readings. The schema is published and designed to be compatible with other fitness apps via import and export.

Usage typically involves recording an activity on a Garmin device, syncing to Garmin Connect, and exporting as TCX (or importing TCX into other apps). TCX files can often be converted to other formats (such as GPX or CSV) with third-party tools, enabling broader analysis and archiving. The structured, human-readable nature of TCX makes it a common choice for athletes who want a machine-readable record of workouts that preserves timing, distance, and sensor data.

Other meanings may exist for the acronym TCX in different domains, but in fitness and activity tracking it most commonly denotes Training Center XML. This article focuses on that usage.