I've lost confidence in my HRM and calorie estimates

givprayz

Has anyone else had this experience. I was a little leery of the calorie burns my HRM was recording, so I decided to perform a little test. I put it back on after showering this morning, and wore it for 6 hours of a regular day at work. I am not completely desk-bound, but I don't do anything more physical than a short leisurely walk while working, and it says I've burned almost 1000 calories. If that were true, I would be losing a lot faster, since I keep my net calories between 1200 and 1400 most days. I feel cheated.

From now on I'm going to assume my daily calorie use without work-outs is about 1900, and that my aggressive work-outs burn about 400 calories. I'm not even going to worry about calories from yoga or strength-training. Maybe it will get me back on track losing each week if I stick to 1300-1600 calories daily, regardless of workout calories.

I'm sure gonna miss that excitement of thinking, "I just burned almost 600 calories before breakfast!"

bstamps12

I always feel like mine grossly underestimates my calories burned. After a 45 minute run, it said i only burned 320 calories, NO WAY! My HR was at 91-96% almost the entire time! MFP said I burned 479 calories...so I have just been averaging the two...

eellis2000

lol mine too. the one i have you have to tell it to check your heart rate and it calculates the calories based on that heart rate till you stop it or check you hr again. i took me awhile to figure this out. i was shocked on day three when it told me i had burned 3000 calories in a day!!!!!!!!!

erickirb

Has anyone else had this experience. I was a little leery of the calorie burns my HRM was recording, so I decided to perform a little test. I put it back on after showering this morning, and wore it for 6 hours of a regular day at work. I am not completely desk-bound, but I don't do anything more physical than a short leisurely walk while working, and it says I've burned almost 1000 calories. If that were true, I would be losing a lot faster, since I keep my net calories between 1200 and 1400 most days. I feel cheated.

From now on I'm going to assume my daily calorie use without work-outs is about 1900, and that my aggressive work-outs burn about 400 calories. I'm not even going to worry about calories from yoga or strength-training. Maybe it will get me back on track losing each week if I stick to 1300-1600 calories daily, regardless of workout calories.

I'm sure gonna miss that excitement of thinking, "I just burned almost 600 calories before breakfast!"

HRMs are not meant to calculate calories burned doing everyday activities. They only work (accurately) when your HR is elevated during exercise. There is no benefit to wearing them all day that number will be way wrong.

Mindful_Trent

HRMs are NOT designed to accurately estimate calorie burn during casual activity (or when you're sedentary). You cannot take that 1000 calorie estimate as accurate. It is only designed to accurately estimate activity when you're actively engaged in a continuous activity (ex. brisk walking, running, rowing, elliptical, cardio class, kickboxing, etc.).

Don't make it more complicated than it has to be - let MFP estimate your normal daily burn, then log your exercise calories based on your HRM. I recommend backing out the portion of that that's attributable to normal burn. So, I normally burn 91 cals/hour based on MFP (your normal daily burn from the goals page, divided by 24 hours). For every hour of exercise, I subtract 91 calories from the estimate. You could also just take the burn your HRM gave you and add 1/2 or 3/4 of those as your exercise calories to MFP to make it simpler.

erickirb

I always feel like mine grossly underestimates my calories burned. After a 45 minute run, it said i only burned 320 calories, NO WAY! My HR was at 91-96% almost the entire time! MFP said I burned 479 calories...so I have just been averaging the two...

As you get more fit you will burn less cals doing the same thing. MFP takes the fitness factor away and assumes you never get more fit. I would go 100% with the HRM not MFP.

bettyboop573

I agree with that...I have been working out for awhile, so it takes a good workout to get my HR up high...so I just dont burn massive calories

royam01

I agree. i bought one at target for almost $100 and I used it once. For a half hour walking workout it said I burned 500 calories. I really doubt that!! I took it back after one day. I felt like it was a waste of money. I would rather underestimate calories burned than overestimate.

tara3103

When you signed up for mfp, it asks you what lifestyle you lead. This way when it assigns you your calorie goals, it takes into account that you are "burning" a certain amt of calories already based on your answer. For example, my daily goal is 1380, but I chose sedentary b/c I mostly sit at a computer. You can't count what calories you burn for "normal" activity during the day.

AnnaPixie

I think you should just use it for exercise. My HRM estimates much lower than MFP too. I take the HRM as being more accurate. Also, as I've had it for a few months, I've notices I burn less and less doing the same exercise class. So that kinda proves to me that it is working as i SHOULD be burning less the fitter I get and more weight I lose.

I dont know what HRM you have. Does it have a chest strap? Is it a recognised name? It may just be that the one you have isn't very good? I dont know, but I definitely think my Polar FT7 is more accurate than MFP

Good luck :flowerforyou:

ChRiStA_1983

I agree. i bought one at target for almost $100 and I used it once. For a half hour walking workout it said I burned 500 calories. I really doubt that!! I took it back after one day. I felt like it was a waste of money. I would rather underestimate calories burned than overestimate.

Did the one that you purchased have a chest strap? Heart Rate Monitors that include a chest strap & transmitter are MUCH more accurate than the simple watch versions that don't utilize the chest strap...

IsMollyReallyHungry

At your size I doubt you are burning 600 calories unless you are exerting yourself for 60 min or more. What brand do you use? This could not be a Polar brand?

I do agree with you that not counting the exercise should boost your weight if you have been eating your calories back because of your exercise. I have even thought of not logging mines period to see how I do.

givprayz

I know they are supposed to be more accurate during aerobic activity, but that shouldn't cause them to be completely inaccurate during regular activity! I mean, my heart rate during class is 125-140, while it's 55-90 while working, so the calculations should still be moderately accurate, while I don't believe this 1000 at all. I think I'll side with the folks who prefer to underestimate exercise calories, and over-estimate calories ingested, figuring it's all just little more than guesses anyway.

But while on the subject of estimates, the calories given for foods that are measured any way but by weight are also crazy inaccurate. I wish those could be deleted from the database. Fluids can be measured by volume, but berries really can't. Just another gripe of mine.

MisdemeanorM

A body media fit or body bugg are good all-day-wear calorie trackers. they are meant to calculate in activity or rest, while HRMs only accurately log higher heart rates. they can be expensive though and require a subscription though to access the info it collects :grumble: but they are pretty cool and being a numbers nerd I like mine.

I do round down on my HRM entries though when wearing it for cardio. it think it calcs cals burned a bit high.

erickirb

I know they are supposed to be more accurate during aerobic activity, but that shouldn't cause them to be completely inaccurate during regular activity! I mean, my heart rate during class is 125-140, while it's 55-90 while working, so the calculations should still be moderately accurate, while I don't believe this 1000 at all. I think I'll side with the folks who prefer to underestimate exercise calories, and over-estimate calories ingested, figuring it's all just little more than guesses anyway.

Sorry but the calculation it uses doesn't work like that, you would need a body bug or something else like that. The calculation built into the HRM needs you HR to be elevated to be correct, a lower HR would need a different calculation to the oxygen intake VO2, and other technical stuff.

MisdemeanorM

But while on the subject of estimates, the calories given for foods that are measured any way but by weight are also crazy inaccurate. I wish those could be deleted from the database. Fluids can be measured by volume, but berries really can't. Just another gripe of mine.

Yeah, but there are many of us who are never going to weigh anything and looking at a database I am more likely to accurately log 1/2 cup of blueberries than try to guess what the grams are. Especially for people who have wiggle room in their diet - I don't necessarily use mine to track every calorie and lose in a specific time period, but just to be more overall aware of the whole picture and recognize trends and for the most part stay in a healthy range of intake. I am MUCH more a visualize an approximate amt than a weight and measure everything person. Should I decide I actually want to nail down and lose a specific amt of weight in a certain time period, I might get on board with the OCD-type weighing measuring, but generally speaking, just being aware of cup size is fine with me. I'm not worried that my oatmeal is off 20- 50 calories in either direction because I scoop or eyeball it rather than weigh, and I am VERY not worried that my blueberry count is off 5 calories because the I measured.

Mindful_Trent

I know they are supposed to be more accurate during aerobic activity, but that shouldn't cause them to be completely inaccurate during regular activity! I mean, my heart rate during class is 125-140, while it's 55-90 while working, so the calculations should still be moderately accurate, while I don't believe this 1000 at all.

Unfortunately, it really CAN'T be relied upon for such estimates. I know it seems like it should be... but the "logic" behind the HRM calculations breaks down when you try to apply it to at-rest or casual activity situations. Your body doesn't work exactly the same way when you're exercising vs at rest or doing casual activity, and it's not necessarily the same relationship between calories burned and heart rate in each of the scenarios.

givprayz

Mine is Timex, with a chest strap, and it changes measurement over time, and from a heavy work-out to a light one, but I think it is over-estimating all of them. I used to log 2/3 to 3/4 of the calories it read, but now I'm just going to ignore exercise calories and stick to a goal range based on appetite. If aI find my net is consistantly higher or lower than I want, I will go back to being more anal about it. I just need to back off from the obsessing over calories in and calories out.
(And I know MFP estimates my normal daily calorie needs. I am actully using their estimate and my experience to say I burn an average of 1900 daily without exercise.)

cmriverside

givprayz,

One more thing, did you set it up for your level of fitness? That makes a difference too, the settings on the HRM. But, yeah, it's not meant for daily activity - get a Body Bugg type device for that.

But while on the subject of estimates, the calories given for foods that are measured any way but by weight are also crazy inaccurate. I wish those could be deleted from the database

A $20 food scale on Amazon takes the guesswork out of this.

lilRicki

Mine completely sabotaged my weight loss...i gained EVERYTHING back that i lost before i wore it. It took me a bit to clue in that I wasn't burning 1000 calories at a work out, but by then it was to late and i was 15lbs heavier. Now i just wear it as an expensive timer. I was pee'd right off. I just use MFP and I've lost my 15lbs again, so I'm back to where I was before. I'm sorry I wouldn't recommend a HRM to anyone anymore, I don't care the make and model. There are tons of calculators on the internet that can help you figure out how many calories you've burned. I just use MFP and I have a whole lot more respect for this site now than I did before.

Trjlove

I recommend an Omron HJ-112 Pedometer. They are a little more expensive but ACCURATE!!! We use them in research.