Acutal Need vs System Calculated

iamhealingmyself

I bought a Polar FT4 yesterday (Sunday) afternoon. As an experiment I wanted to see what I actually burned during my normal day so I wore this for the better part of 24 hours from midnight (Sunday) to midnight (Monday) roughly as there was actually about an 8 minute gap from where I took it off and when I had a minor malfunction this morning. So overall I'd think this recorded my day pretty well. I would consider this an average activity day for me. I received some interesting readings which have led me to question the calculations online and/or the accuracy of this item.

Note, when first setup it does ask for my height, weight, dob and gender. I do have a large frame, as I'm 6'1" so that might account for something in the heart rate calculation not considered in the MFP formula. I did not engage in any type of exercise, workout, routine or other method of conscious calorie burn.

Here is what I learned:
Total test time burn: 3846 calories (+/- 160 calories an hour)
from Midnight to 7:42am (point of malfunction) I burned 1125 calories. I slept from shortly after midnight to about 5:40 this morning. Almost 600 of the 1125 were burned in my sleep. :huh:
From 7:45ish am (point of corrected malfunction) to 11:52pm I burned 2721 calories. I went to work at 6:30a - mostly sat at my desk until about 3:15, went home, relaxed for about 20 minutes, went to look at a couple of houses with my kids (leisurely walking, nothing crazy, still dressed from work) then went home, made some soup for dinner, ate and then have been lying down reading messages on MFP until it was time to stop the test. The only real difference is that I stayed up til midnight both nights to get readings but it was basically doing the same things- walking around inside of house, reading message boards, watching tv, etc. Lately I've been asleep around 10.

My average heart rate for the test period is 81 bpm and my highest was 128bpm.
To me, the total calories burned and the avg bpm seems a little high. I do not have HBP, or any other treated illness. I am on 1 medication for pain management but it's a muscle relaxer and it's very very low dose. Only other physical change is TOM since last night. I don't know if that has any affect on HR or calorie burn/needs other than they stereotypical chocolate fix (of which I have not had). I only had 1 cup of coffee as I have for several weeks now. I used to drink much more.

MFP (and other calculators) say that based on my height, weight, gender and age I burn 2050 calories with a sedentary lifestyle. I have a desk job and really only get up to go to the bathroom and one time daily to a short meeting at end of my row. I've been trying to get a regular exercise routine going but am fighting tough resistance in my back so I really have to be careful. That's another reason I wanted a more accurate reading of what I burn in a normal day so that I know how to adjust my foods according to my inability to exercise consistently and still be able to lose weight.

How can there be 796 calorie difference using the same factors? which one is more likely right?
Even if I changed my activity levels on MFP I could not get the system to tell me my daily normal activity calories were more than 2540. I do NOT consider myself very active by MFP standards.

I was hoping to be able to better adjust my goals based on what I learned from these readings. For some reason when I removed all exercise from my goals and lost 11lbs, MFP told me to eat 20 more calories a day than I previously had.

I don't know what to believe or how to adjust. I get the whole thing about not underfeeding your body and exercise calories. That's why I'm surprised to see such a large deficit between the meter and the formula just in normal activity burn. If I calculate the 3500 calories a week deficit off of the meter number, I need to eat 3346 calories a day to lose 1lb a week.

What would those in the know recommend? Did I not calibrate something correctly during initial setup? Does my larger body really need all those calories? My weight has kind of stalled over the past 2-3 weeks. I've been juggling about 1/2 - 1lb that keeps finding it's way back to me every few days. I'm going to check out their website, but I did read the included manual (all 12 pages of English) before I started.

Thanks for all thoughts and suggestions in advance.

taletreader

A heart rate monitor is *not* going to be accurate for such an exercise. It's going to give you a reasonable value, within a few 100 cal over an hour or so, for aerobic activities for which its basic formula is reasonably applicable. It does VERY badly for "just moving around" and can't distinguish at all between a heart rate that's elevated because you're nervous and a heart rate that's elevated because you're doing aerobic exercise.

It'll also overestimate strength training activities as well as complete rest.

Given that your heart rate never even hit 130, you weren't spending much of your day with activitis the calorie counter in your HRM is a useful tool for.