Vivofit 2 and optional HRM

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Hi all-

I recently started working out with the HRM and Vivofit 2. I am wondering if anyone has experience with the calories burned with the Garmin HRM. Is it accurate? I am doing workout from Fitnessblender.com, so usually they involve HITT and strength training. I just want to make sure I am not eating back too many exercise calories, but I am worried the HRM is giving me too many calories burned.