There’s a summary of the state of things regarding exercise and wearables archetypes in this Discourse post from @erik.sundvall as of 2022 here: Example wearables integrations and standardizing in OpenEHR using HL7, etc, for GDL CDS tools? - #8 by erik.sundvall
I’m not aware of anyone trying to finalise, review and publish a set of archetypes for these purposes, but it would be very welcome if someone wanted to undertake that work.