endurain might be able tot be combines with Fitotrack or Opentrack tot get an steava-like experience?

OpenTracks works for running and includes maps

Don't think there are any for this purpose. But maybe you can wrap something up. For example, if one such service like Strava has RSS, you could set a bot to share. Furthermore, iirc the user can set his Friendica account to make automated posts while still being a personal account.

Also, maybe also look if a tracking service has integration to an ActivityPub-compatible platform, or even to platforms that can be bridged to ActivityPub. For example Wordpress (seem pretty powerful from what I've seen) and Bluesky (can be bridged to ActivityPub through Bridgy Fed, Friendica, Wafrn and maybe some other service I'm forgetting).

In this idea of nested bridging and RSS, if a tracking app lets you post to Twitter, you could make an RSS reader bot or a Friendica account to read the feed a Nitter instance would provide for your Twitter account.

And in this idea of nested bridging, alternatively and if all steps are possible, to find an app that lets you share to Facebook or Instagram, then share the post to Threads while it has ActivityPub integration active. Not sure if it's indeed viable as I don't use either of the 3.

Also maybe Misskey or PieFed could help? Apparently both have pretty powerful CSS-based user extension capabilities.

And not an immediate solution, but to keep fomenting the idea of having an ActivityPub alternative for that? Or even getting someone to make it, though people don't usually seem to like to make software for one person if they're not being paid and they don't see a bigger advantage to making the software.