A Strava data export exists in two separate forms that people routinely confuse. One downloads a single activity as a route file. The other requests a complete archive of the whole account. They contain different things, arrive by different routes, and only one of them preserves what your device originally recorded.
The bulk archive
The archive is requested from the account settings, prepared in the background and delivered as a download link by email, usually within a few hours. It contains your activities in their original uploaded form, plus profile information, comments, kudos, segment efforts and the rest of the account history as separate files.
The important property is that original files come back as originals. A ride uploaded as a FIT file returns as a FIT file, with every channel the device recorded, including ones the web interface never displays. For anyone moving platforms or keeping a personal archive, this is the route that matters.
Single-activity download
The per-activity export produces a GPX file, which is a reconstruction and not the original upload. It carries position, elevation and time, and nothing else. It does not carry power, cadence, heart rate or temperature, because GPX has no standard place to put them and the export does not invent one.
That makes it the right choice for sharing a route with somebody and precisely the wrong choice for preserving a ride. People tend to discover this only after deleting an account, when the tidy folder of GPX files turns out to have discarded every physiological channel the original recording contained.
What each format actually preserves
FIT is the native format of most head units. It is compact, binary, and carries every channel the device measured. TCX is XML, considerably more verbose, and carries most of them. GPX is also XML, the most widely supported of the three, and carries the least. Support and fidelity run in opposite directions.
The practical consequence is that conversion between them is lossy in one direction only. A FIT file can become a GPX file at the cost of everything except the track itself. A GPX file cannot become a FIT file with power in it, because the information was discarded and cannot be recovered.
| GPX | TCX | FIT | |
|---|---|---|---|
| Position and time | Yes | Yes | Yes |
| Elevation | Yes | Yes | Yes |
| Heart rate | Extension only | Yes | Yes |
| Power | Extension only | Yes | Yes |
| Cadence | Extension only | Yes | Yes |
| Laps and device detail | No | Partly | Yes |
| Readable as text | Yes | Yes | No |
What never leaves
Derived and social data is, for the most part, not portable at all. Segment leaderboard positions, achievements, follower relationships and the platform's own fitness modelling are properties of the service, not of your rides. An export hands you only the inputs; the outputs are either rebuilt elsewhere from scratch or simply lost.
This is worth planning carefully before a migration and not discovering afterwards. Activities transfer well, history transfers adequately, and competitive standing transfers not at all. Anyone moving platforms because of a leaderboard position should understand clearly that the position itself is the one thing that can never come along with them.
Data export questions
How long does a bulk Strava data export take?
Usually a few hours, occasionally longer for accounts with many years of activities. It is prepared in the background and announced by email instead of downloaded immediately, so request it before you need it rather than on the day you close the account. A standing habit of taking one every few months costs nothing and removes the problem.
Does the GPX download include my power data?
Not in a form most software reads. GPX has no standard element for power, so the per-activity download is effectively a track with elevation and time. If you need the physiological channels, take the bulk archive, which returns the original file your device wrote. Some tools read power from a GPX extension, but nothing guarantees it survives the round trip.
Can I convert GPX back to FIT and recover power?
No. Conversion cannot restore information that was never in the file. A GPX produced from a ride with power contains no power, and any tool claiming to reconstruct it is inferring values from speed and gradient instead of recovering what the meter measured. Those figures are an estimate wearing the label of a measurement, which is worse than none.
Are my original uploads kept indefinitely?
They are retained as uploaded and returned in the archive, which is why the archive is the trustworthy route. Relying on that indefinitely is still unwise: an account closure, accidental or otherwise, takes the originals with it unless an export was taken first. Treat the platform as a convenient copy of your history, not the only one.
What is the fastest way to move to another platform?
Request the bulk archive, then use the destination platform's own bulk importer on the original files. Importing FIT files preserves every channel; importing GPX files silently produces a history with no power or heart rate, which is difficult to notice until you look for it. Check one old activity for heart rate before you delete anything at the far end.
Related: the GPX audit reads exported GPX and TCX files directly, and the tracking apps section covers the platforms these files move between.