Even with a HRM I think it would be challenging especially for strengthing moves. I always wonder that just in general. MFP gives you a space to do strengthining moves but no space for calorie content, and you know you have to be burning calories doing those exercises along with the after burn. From what I've been seeing in from the alpha videos people have been burning anywhere between 230-350 calories, again that's what their HRM states. I haven't done it before, but I am always on the low end so I am estimating my burn will be around 200 or so. There has to be an app out there that estimates burn from strengthing exercises, I'm going to take a look around if I find anything I will report back.

I do use a HRM and doing Alpha Cardio I burned 335 cals.