BodyBattery

I woke up with a battery level of 57% after almost nine hours of high-quality sleep last night. My body does feel a bit run down after running each day over the past couple of weeks. 

I usually get 7 hrs sleep and a full "charge" in the morning. This morning I slept in and got 8 1/2 hrs.  Body Battery gave me a level of 56%. I've only had the watch just under two weeks. I'll give it a little longer and see if the stats starting making sense before I delete the widget and tab in GCM. 

Seems about right for me, I get very little recharge overnight if I've had a late night and alcohol, and my HR is higher overnight. A decent nights rest with a lower resting HR (only 5-8bpm difference) and I get a much better recharge.

I'm liking it so far.

I would give it a full month to see if the Body Battery better tracks how you actually feel.

That’s pretty much what I’ve been seeing as well.

Theres really nothing predictive about it so not much use in real time but might be if you’re reviewing runs from a week or two previous and explaining workouts where you underperformed that you might not recall feeling tired that day. (Shrug)

Yes I Think it need some time to learn you - but from a physiological and logical standpoint body battery should never hit the 0 or the 100 - I think those algorithms are better than in the vivosmart 4 but still needs some tweaking here and there :)

I guess after an ironman one could see 0, anyone did one already ? 

I saw 5 after an all-out interval session a few days after a hard race. I went o bed very early that day!

Mine got down to 9 after a 6hr30, 28 mile trail run with 1600m of climbing. An 8 hour sleep only brought me back up to 16, and then by the end of that day was down to 8. It was only after the next full nights sleep that I was back up in the 60's. 

I like the feature a lot and feel like it works really well.