HRM cals v's MFP and machines

Yep...go with your HRM!!

Well i have just used my HRM for the first time. The cross trainer and MFP are way out. Crosstrainer and MFP reckon i should have burned around 150cals. My HRM says i have done 90cals. I know me exercise wasn't very long at 20 mintes long but i have broken into a sweat. if the HRM is the most accurate no wonder i wasn't losing weight last time cos i was eating way more cals than i should have done. what do you all think. xo

This could mean that MFP is outta whack or that it is assuming that for your age/weight and exercise being performed you are hitting a higher HR.... One purpose of using a HRM is to assure you are reaching your target rate or zone for your intended results ie. fatburn, cardio, peak etc.

That said, yes, your HRM will give you a more accurate idea of cals burned so you should enter it manually.

Here's a link to calculate your target zone: http://www.mayoclinic.com/health/target-heart-rate/SM00083

That's why a HRM monitor is one of the best investments when you're serious about this. For me it's a must-have can't-do without.

I've had a similar worry since I started using the Runkeeper app a week or so ago - it gives me way more calories than MFP does for all of my activities. Really don't know which to trust! My weight is staying pretty solidly steady, despite getting some serious long miles in.

Not sure what's best to do?

I use runkeeper too. I find that it depends on the activity I am doing (usually MFP is higher), but I ALWAYS go with the lower number to allow for some wiggle room. But I don't have the HRM (Wahoo) add-on that goes with it. I am looking at it now, and once I get that, I will be going with that #.