Circuit Training Calories Burned

alexjh1990

I thought of adding some home circuit training back to my fitness routine. I used to do The 30 Day Shred, and even though it worked me out, for some reason I didn't quiet like it. Whenever I can't enjoy a workout at least a bit, even if it's hard and kicking my butt, I just can't make myself do it.

So, kind of following her 3 2 1 Circuit Layout with 3 min. Strength, 2 min. Cardio, 1 min Abs- I've decided to throw together my own Circuit Training routine.

Tomorrow I'll be focusing on Chest, Triceps, Biceps (hopefully finding some compound moves to include legs as well). I guess I'll go for about 20 min or so (I won't hit every minute on the dot).

My question is this, and please bare with me (I know some of you absolutely hate questions like this and I can already anticipate some of the possible answers):
Though I know that the only way to get a good estimate on how many calories I burn during exercise is to use a trusted HRM, but I don't have one so that is out of the question at the moment. Also, MFP seems to overestimate on nearly every activity for calories burned (at least for what I know in relation to when I was able to use a HRM a few times). As for the other online calculators separate from this site, it's hard to know if the estimate is correct when the activity listed is not specific in the type of circuit training it is.
So I was wondering if anyone could help me out in figuring out an estimate on possible calories burned for me during 20 min of the type of circuit training I described.
Maybe someone does circuit training with a HRM and is sort of close to my stats and could share what they burn.

21 yo. F 144lbs 5'3"

Any help is greatly appreciated.