Polar
Export your Polar Flow data and keep your full history
If you have worn a Polar for a few years, Polar Flow holds a long record of your training, your nights and your recovery. Connect any other app to your Polar account, though, and it sees about four weeks of it. The rest is still there, but only one route gets it out in one piece: Polar’s own data export.
This guide covers why apps only see the last month, how to request the export, what the file contains, and how to keep Nightly Recharge and sleep history from here on.
Short answer
Sign in at account.polar.com, choose Download your data in the left menu and click Download. Polar emails you when the archive is ready, and the link works for two weeks. You get one ZIP of JSON files covering your whole account. Keep it as a backup, and import it into an app that reads it, because Polar’s API only shows other apps the last 28 to 30 days.
Why other apps only see four weeks
Apps connect to Polar through AccessLink, Polar’s official API. Its documentation sets the limits plainly:
- Sleep, Nightly Recharge and cardio load are returned for the last 28 days.
- Workouts are returned only if they were uploaded to Flow in the last 30 days, and only if they were uploaded after you connected that app.
- Daily activity summaries reach further back, up to a year.
So an app you connect today starts with a month of sleep and recovery trends, however long you have been a Polar user. And because the window rolls forward every day, a night the app doesn’t store within those 28 days is out of its reach for good.
The Flow web service can export single workouts as FIT, TCX, GPX or CSV files, one session at a time. That works for moving a few runs to another platform. It doesn’t cover sleep, 24/7 heart rate or Nightly Recharge, and it isn’t practical for thousands of sessions.
How to request your Polar data export
These are Polar’s steps as of 28 September 2026. They work in any browser, including Safari on your iPhone:
- Go to account.polar.com and sign in with your Polar account, the same email and password you use for Polar Flow.
- In the left menu, choose Download your data.
- Click Download to start the request.
- Wait for Polar’s email. Polar doesn’t promise a time: it depends on how much data you have and how busy the service is. Expect anything from minutes to about a day.
- Download the ZIP from the link in the email within two weeks. The file name starts with
polar-user-data-export.
A long history makes a big file. One 19-year archive we examined came to 6.9 GB once unzipped, so download it on Wi-Fi and check you have the space.
What’s inside the export
Polar’s help page is cautious here. It says the export includes the data you provided and most of the data from your Polar devices and apps, but not values Polar’s algorithms derive, and it names activity and sleep as examples. The real export we examined in August 2026 held more than that description suggests:
| In the export | What it holds |
|---|---|
| Training sessions | One file per workout: sport, time, distance, heart rate, speed, cadence, altitude and power samples, the GPS route, zones, cardio load and muscle load |
| 24/7 heart rate | One file per month of continuous heart-rate samples |
| Sleep | Every night with sleep start, end and the full sequence of sleep stages |
| Sleep score | The score for each night and its parts |
| Nightly Recharge | ANS charge, overnight HRV (RMSSD), breathing rate and heart rate for each night |
| Daily activity | One file per day with steps, calories and time spent at each activity level |
| Physical info | Weight, maximum and resting heart rate, VO2max and thresholds as you entered them over time |
| Raw and test data | Beat-to-beat intervals. Watches with the sensors for them also add SpO2, skin-temperature and ECG test files |
Everything is JSON, not FIT, GPX or TCX, so Strava, Garmin Connect or TrainingPeaks can’t open it directly. A few things we did not find in it: the daily cardio-load status (strain and tolerance) and SleepWise alertness data. What your own file holds can vary with your devices and the age of your account.
What to do with the file
First, keep a copy. The ZIP is the most complete record of your Polar years that you can hold yourself. It contains detailed health data, so store it somewhere private, such as your own iCloud Drive or an external disk, not a shared folder.
Second, put it to use. Keho reads the export on your iPhone and brings it into its statistics:
- In Keho, open Profile, then Polar, and choose Import full history.
- Tap Choose the export and pick the ZIP just as Polar sent it. There is no need to unzip it.
- Keho lists what it found (workouts, nights, months of heart rate, activity days) and how long the import will take, before anything is written.
- Tap Start import, keep Keho open and the iPhone on power. You can stop at any time; picking the same file again continues where it left off.
Workouts with heart rate and routes, sleep stages, 24/7 heart rate and breathing rate go into Apple Health, where it has a type for them. Nightly Recharge, sleep scores and each workout’s cardio and muscle load go into Keho’s storage on your iPhone. Your trends, records and training load then reach as far back as your Polar account does. Workouts already in Apple Health, from Polar Flow, your watch or another app, are recognised and skipped, and importing twice replaces entries instead of adding copies.
A few limits, stated plainly. If Polar Flow is the app that writes your workouts to Apple Health, imported workouts stay in Keho’s statistics so they don’t appear twice. Per-second workout charts are kept for the last three years; older workouts still import with their heart rate, route and load. SpO2 and skin-temperature tests, raw beat-to-beat data and ECG stay in the file untouched. The import is part of Polar Sync, which starts with a free month, and it doesn’t need a Polar connection, so it also works if you have moved to another watch. The file is read on your iPhone; your health data never leaves it.
Keep Nightly Recharge and sleep history from now on
An export is a snapshot. To keep the history growing, something has to collect the new nights before they fall out of the 28-day window. Once you connect Keho to Polar, it stores Nightly Recharge (ANS charge, HRV, breathing), sleep score, the daily cardio-load status, SleepWise and Running Index on your iPhone from that day on, and every sync adds the newest days. Together with a one-time import, that gives you one continuous record: years from the export, and every day since from the sync. Sleep stages and 24/7 heart rate go into Apple Health as they arrive.
Nothing in that store is deleted behind your back. If you disconnect Polar, Keho asks whether to keep the data or erase it. If you want a fresh backup later, you can request a new export from your Polar account.
Common questions
How long does the Polar data export take?
Polar gives no fixed time. It depends on how much data your account holds and how many requests are queued. Minutes to about a day is typical, and the download link stays valid for two weeks after the email arrives.
Does the export include Nightly Recharge history?
In the export we examined, yes: every night since Nightly Recharge started, with ANS charge, HRV and breathing rate. Polar’s help page says derived values may be left out, so check what your own archive contains. Keho shows a list before it imports anything.
Can I open the export in Strava or Garmin Connect?
Not directly. The export is JSON. For individual workouts, the Flow web service exports FIT, TCX and GPX files that those platforms accept.
Why does a new app only show four weeks of my Polar data?
Because Polar’s API serves only the last 28 days of sleep and recovery and the last 30 days of workouts. Anything older has to come from the export.
Sources: Polar support, “How to download all your data from the Polar ecosystem”; Polar support, “How do I export individual training sessions from Polar Flow web service?”; Polar AccessLink API documentation. All checked on 28 September 2026. Keho is an independent app and not affiliated with Polar Electro Oy.