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Connecting Polar

Status: Available

Polar connects directly to Runsei. Your runs and recovery arrive after they sync to Polar Flow.

What Runsei reads from it

  • Runs: distance, time, pace and heart rate, with laps and route when Polar shares them
  • Recovery: sleep and Nightly Recharge

What Runsei can send to it

Planned sessions: no.

  • Runsei does not send planned sessions to a Polar watch. Polar offers no way to do it.
  • Choose Download workout (.fit) from a session’s menu and load the file yourself.

How to connect, step by step

  1. In Runsei open Profile, then Connections, on the web or on the phone.
  2. Find Polar and tap Connect.
  3. Polar’s own sign-in opens. Approve access (Polar may ask you to accept its terms first) and you come back to Runsei.
  4. After a run syncs to Polar Flow, it arrives in Runsei shortly afterwards.

What does not work

  • Polar is new in Runsei. Expect rough edges while we test it with real watches.
  • Polar data is not shared with the AI coach. Your Polar runs and recovery appear in Runsei, but the coach does not read them.
  • Polar lists only the last 30 days of runs, so a run older than that cannot be imported.
  • Runsei never changes anything in your Polar account. Disconnecting stops new data and removes the Polar runs and recovery Runsei imported.

What you need

Phone
Any phone with the Runsei app, or the web app.
App build
A current Runsei app. Nothing special to install.
Watch models
A Polar watch that syncs to Polar Flow. We have not listed any Polar model yet.

Compatible devices

Last checked 30 Oct 2026. Tested means someone used that exact model with Runsei. Should work means the code or the maker’s own pages say it does, not yet tried on that model. Not supported and Not known are what they say.

  • Polar Vantage V3

    Should work
    Runs to Runsei
    Not yet
    Sessions to the watch
    Not supported by Polar*
    Heart rate
    Not yet
    Sleep
    Not known
    HRV / recovery
    Not known

  • Polar Vantage M3, Vantage V2, Vantage M2

    Should work
    Runs to Runsei
    Not yet
    Sessions to the watch
    Not supported by Polar*
    Heart rate
    Not yet
    Sleep
    Not yet
    HRV / recovery
    Not yet

  • Polar Grit X2, Grit X2 Pro, Grit X Pro

    Should work
    Runs to Runsei
    Not yet
    Sessions to the watch
    Not supported by Polar*
    Heart rate
    Not yet
    Sleep
    Not yet
    HRV / recovery
    Not yet

  • Polar Pacer, Pacer Pro

    Should work
    Runs to Runsei
    Not yet
    Sessions to the watch
    Not supported by Polar*
    Heart rate
    Not yet
    Sleep
    Not yet
    HRV / recovery
    Not yet

  • Polar Ignite 2, Ignite 3

    Should work
    Runs to Runsei
    Not yet
    Sessions to the watch
    Not supported by Polar*
    Heart rate
    Not yet
    Sleep
    Not yet
    HRV / recovery
    Not yet

  • Polar Unite, Loop

    Not known
    Runs to Runsei
    Not known
    Sessions to the watch
    Not supported by Polar*
    Heart rate
    Not known
    Sleep
    Not yet
    HRV / recovery
    Not yet

  • Polar Street X

    Should work
    Runs to Runsei
    Not yet
    Sessions to the watch
    Not supported by Polar*
    Heart rate
    Not yet
    Sleep
    Not yet
    HRV / recovery
    Not yet

*Polar's open interface (its API) cannot send planned sessions to a watch. This is a limit on Polar's side, not something Runsei is missing. The watch itself follows plans made in Polar Flow; whether a partner route exists is not confirmed.

Not tested yet

  • Every Polar watch: not tested yet on a real watch.
  • Polar sleep and Nightly Recharge values: not checked against Polar Flow yet.

More

Brand names and logos belong to their owners. Runsei is not endorsed by, sponsored by or affiliated with them. Health data you connect is stored in the EU and is never used to train anyone’s models.