Hello,
In fact there is an activit type "Obstacle running" in Garmin Connect this could be used for "fitness trail" / "trim trail" or "parcourse".
In fact I really miss this on Garmin6/7/Epix, in fact it shall not be much more then an extra running profile where activities will not take into account for stats related to performance (ex: VO2Max).
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I just found an interesting page with a similar request for the Fenix5:
