10 min in the sauna didn't do much to my HR after swimming. It was about 120°F in the sauna.

Edit: temps are 140-150 degrees F

I just happened to be wearing my watch and turned it on for kicks. This is where I started at 10 min. I've moved to 20 min but haven't recorded the session since these two. Maybe I'll start again.

https://connect.garmin.com/.../activity/3625003499

https://connect.garmin.com/.../activity/3606138182