[Davide Carozza]

I used the elliptical this morning and my heart rate was consistently in the "Very hard" range as classified by the Health app. Yet the Cardio benefit score was "Light." This always happens to me. There seems to be a heart rate threshold above which the Band and/or Microsoft Health decides you are no longer getting a good cardio workout. Maybe the threshold is an aerobic vs. anaerobic thing? Has anyone else noticed this? Screenshot included.

[Davide Carozza]

As opposed to this, on an exercise bike and clearly a less difficult workout but with a much higher Cardio benefit mark:

[Nate Silver]

I think it might be more a function of using the 'exercise' activity vs 'bike' activity. I bet if you did two similar (but easier and harder) activities both utilizing the same tile, you'd see consistent Cardio benefit. You could do it with two 'runs', or two 'bikes' and see. There may be something broken with the way the 'exercise' tile is recognizing cardio benefit? This wouldn't surprise me at all, since the 'exercise' function is more geared towards strength training rather than cardio. Not saying I agree with it working this way, just saying that I think it might be a built-in bias against the ability of strength training to provide significant cardio benefit. Sort of makes you wonder about the rationale behind the algorithms, if prolonged hard heart rate based activity is discounted solely based on use of the 'exercise' tile.

[Davide Carozza]

Thanks Nate, that's a great point I hadn't considered. I bet you're right. Though as you say, it still isn't great, since I chose the elliptical setting in the exercise tile (obviously)--it should be classified as a cardio activity. Not much point in having an elliptical setting otherwise. Next time I'm on the elliptical maybe I'll try calling it a run, though that might hurt my Vo2. Still, worth a shot.