GPX to Excel: Analysing Your Garmin Training Data

Garmin, Wahoo, Suunto, and Polar devices record every training session as a GPX or FIT file — latitude, longitude, elevation, heart rate, cadence, speed, and timestamps at 1-second intervals. The data is rich but locked in a proprietary format most athletes never access directly. Exporting to CSV opens the entire dataset to Excel, Google Sheets, or Python for custom analysis.

To export from Garmin Connect, go to the activity → three-dot menu → Export to GPX. From Strava, go to the activity → Export GPX. The resulting file is XML-formatted with trackpoints containing lat, lon, elevation, and time tags. Additional sensor data such as heart rate and cadence appears in Garmin extension tags. A converter extracts each trackpoint as a spreadsheet row, giving you columns for timestamp, latitude, longitude, elevation in metres, heart rate in BPM, and calculated speed.

With the data in Excel, you can chart elevation gain over distance, calculate average heart rate per kilometre split, identify power output zones from cadence and speed, or compare multiple sessions on the same route. Athletes preparing for events use this to spot pacing drift, flag anomalous heart rate spikes, and build custom training load models that Garmin's own dashboard does not provide.