The Apple Watch with the built-in trainer seems to be as safe as your iPhone (if you have one). Maybe don’t connect additional devices or Apps to it / restrict access… Yes it can be an additional motivation to overcome any laziness if that’s the case… ;)
Discussion
I assume anything my iphone or apple watch knows is known by apple and therefore shared with services at request. 🤷♂️ would be nice to be wrong!
Well, off-grid living without internet is the last option, timing your training with a mech watch and writing it down on a piece of paper is an option! 😂