Why Apple Watch Ultra 2 does not read HR every second on cycling mode? This feature is extremely important to warranty a accurate calorie burn reading.

The calories burn in ultra 2 has a huge difference. Apple Watch is very inaccurate measuring Cal burning in the sport mode; while my polar grit x and polar sensor H10 indicate 1200 calories burned in one hrs intense MTB ride, the Ultra 2 said I burned only 580 cal, it’s a huge difference and probably it is due to Apple Watch does not have continuous HR reading (every second)