Yeah, it absolutely underestimates your calorie count.
If they programmed it that way intentionally, I wonder if they were just trying to be conservative so people didn't get their hopes up that they were burning tons of calories. I mean, maybe I'd be more frustrated if it said I burned MORE calories than seemed true.
Anyway, my personal experience is like this: I really give it my all when using YSFE2012; my heart pumps hard and I get seriously out of breath. I keep this intensity for up to an hour. When I'm done, I log the calories here on SparkPeople. Even though I know it's too low, I've been logging what it gives me because I'm the type that'd rather underestimate than overestimate.
I have compared the numbers I've gotten to calculators here on SP. It's usually TWICE AS MANY calories burned if I list it as moderate calisthenics or cardio. My heart rate monitor is the one I actually trust the least because it's saying I'm getting three times as much calorie burn as YSFE2012 calculates. To me, that's crazy. I actually trust my HRM the least, because if I was really burning that many calories, I'd be super fit (I'm not).
Anyway, don't trust it too much. It's sad, but it just isn't giving you the credit you deserve after a workout,
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