How accurate is HRM when it comes to calorie burn.

georgebrown10

Hi, I am not sure if this topic has been done however I am keen on knowing how accurate HRM are? For some reason I feel as if it overestimates your calorie burn which is annoying but thats me making an assumation. Can anyone clarify how accurate it is.

Thanking you in advance

talysshade

If it's one with a chest band it's very accurate.

mzenzer

It's very accurate, and as accurate as it's going to get compared to any other method out there. Just make sure your stats are entered into it correctly and that you update your weight as you lose. Also, remember, depending on your resting metobolic rate, you need to subtract a certain amount of calories per hour from what your HRM says. For example, my RMR is about 80 calories, meaning I'd burn that in an hour laying on the couch staring at the ceiling. So if my HRM says I burned 580 calories, I subtract 80 calories leaving 500 as what I burned due to exercise.

tmthorn0927

I have one with a chest strap and I think it is low! So who knows. I don't make it my end all. As long as I am active I am good with whatever burn comes with that.

twinmama1987

I think mine is accurate.. more so than a few others. Mine has a chest strap.. but some seem a bit .... generous, i guess.

thumper44

Yes chest strap is very accurate. Better than any machine you would use.

Give us some examples,

VParee

I have the Poloar Ft7 and got to say its pretty accurate. Everytime i have a weightloss i update it to make sure and only wear it when working out

ashkaps

I was also wondering this. I have the Polar FT4 with chest strap and sometimes feel that maybe the calorie counter is being over-estimated. But I'm not sure at all. Also, a question do people leave the timer on during weights the whole time or do you stop and start the watch at each set. I leave it running even when I'm resting between each sets. Is this bad? Inaccurate when measuring calories burned in a work out?

Thanks

BerryH

It's as accurate as it can be from just measuring your heart rate. A fully assessment requires being fully wired up with a respiratory meter and all those other instruments you see people in laboratory wired up with that give a full assessment of metabolic rate.

One thing that may be giving you a high burn is that it incorporates the calories you'd be burning at rest too, so don't count these twice. If your BMR is 1500 calories in 24 hours, you'd be burning 62.5 calories at rest. If you run for an hour , your HRM might say you've burned 600 calories, but you should record 537.5 as MFP already takes your BMR into account.

Hope that makes sense!

W0zzie

Polar FT7 here - and I consider it quite accurate.

Just remember to update your stats if you lose - been caught on that once or twice. It can only work with what you give it - bad input = bad output LOL

Brownski860

Does the chest strap go below the boobs or above.. i'm confused. The instructions say chest muscle but shows the bottom of the pectoral muscle on a man! UGH! HELP!

BerryH

Does the chest strap go below the boobs or above.. i'm confused. The instructions say chest muscle but shows the bottom of the pectoral muscle on a man! UGH! HELP!

Just below the boobs, under the strap of your sports bra.

thumper44

It's very accurate, and as accurate as it's going to get compared to any other method out there. Just make sure your stats are entered into it correctly and that you update your weight as you lose. Also, remember, depending on your resting metobolic rate, you need to subtract a certain amount of calories per hour from what your HRM says. For example, my RMR is about 80 calories, meaning I'd burn that in an hour laying on the couch staring at the ceiling. So if my HRM says I burned 580 calories, I subtract 80 calories leaving 500 as what I burned due to exercise.

I totally understand, but I think it a little differently.

You burned 580 calories in an hour, and RMR is 80 calories, so 580-80 = 500 calorie burn as you stated above.
But, during that hour you burned almost 10 calories / min on average, not 1.333/min like in RMR

When most people finish exercising they are not cooled down when they look at their HRM for that 580 total.
So for the next 10-15 mins while they are cooling down, getting their heart rate down, most people will burn another 80 calories very easily. You can't just shut your body down from burning 10 calories / min.?

So, is all that extra math needed?

purplepollypops

I've found mine (which was really cheap, only £14.99 from Lloyds Pharmacy) to be very accurate. I was seriously overestimating my calorie burn before I got it and now it makes me work harder to gain an extra 2 or 300 cals.

erickirb

It's as accurate as it can be from just measuring your heart rate. A fully assessment requires being fully wired up with a respiratory meter and all those other instruments you see people in laboratory wired up with that give a full assessment of metabolic rate.

One thing that may be giving you a high burn is that it incorporates the calories you'd be burning at rest too, so don't count these twice. If your BMR is 1500 calories in 24 hours, you'd be burning 62.5 calories at rest. If you run for an hour , your HRM might say you've burned 600 calories, but you should record 537.5 as MFP already takes your BMR into account.

Hope that makes sense!

Ditto the resting calroies should be backed out, but I would argue that you should be backing out maintenance calories, not BMR, as if you did not workout you would be doing something else (sitting, walking, etc) and BMR is the amount you burn in a coma. So you should actually back out maintenance (may only make 0.25 to 0.5 cals/minute difference from using BMR, but it will make a difference the longer your workouts are) So if you BMR is 1500 and you are sedentary your maintenance will be around 1800 which is 75/hour (1800/24, 12.5 higher than using BMR only) so if your HRM says 600 in one hour you should really only enter 525 (600-75) into MFP to eat back.

To get your maintenance calories go to your goals page and look at calories burned from normal activity, that is maintenance calories.

erickirb

It's very accurate, and as accurate as it's going to get compared to any other method out there. Just make sure your stats are entered into it correctly and that you update your weight as you lose. Also, remember, depending on your resting metobolic rate, you need to subtract a certain amount of calories per hour from what your HRM says. For example, my RMR is about 80 calories, meaning I'd burn that in an hour laying on the couch staring at the ceiling. So if my HRM says I burned 580 calories, I subtract 80 calories leaving 500 as what I burned due to exercise.

I totally understand, but I think it a little differently.

You burned 580 calories in an hour, and RMR is 80 calories, so 580-80 = 500 calorie burn as you stated above.
But, during that hour you burned almost 10 calories / min on average, not 1.333/min like in RMR

When most people finish exercising they are not cooled down when they look at their HRM for that 580 total.
So for the next 10-15 mins while they are cooling down, getting their heart rate down, most people will burn another 80 calories very easily. You can't just shut your body down from burning 10 calories / min.?

So, is all that extra math needed?

I see your point but many HRM users keep theirs on until they finish the cool down, once you are no longer moving, even if you HR is elevated you don't burn much more than you would at rest. Your HRM might show that you do, but it is assuming in the calculation that you are still moving and calculates HR as the only variable, which is not accurate, when you are not performing exercise.

ashkaps

Also, a question do people leave the timer on during weights the whole time or do you stop and start the watch at each set. I leave it running even when I'm resting between each sets. Is this bad? Inaccurate when measuring calories burned in a work out?

Thanks

Anyone?

mocha76

interesting discussion. bump!

erickirb

Also, a question do people leave the timer on during weights the whole time or do you stop and start the watch at each set. I leave it running even when I'm resting between each sets. Is this bad? Inaccurate when measuring calories burned in a work out?

Thanks

Anyone?

You can leave it on for circuit training, very little rest, may slightly overestimate the burn, but if you stop while you are resting during no circuit strength training you will under estimate, while leaving it on will overestimate. HRM's do an okay job estimating calories burned while strength training, but are way more accurate and the embedded calculation in the HRM is designed to give you calories burned doing aerobic (cardio) activity.

georgebrown10

All these reponses have been helpful. I am just trying to make sure its not overestimating as that would just annoy me.

CeleryStalker

They vary, to be honest. I have a HRM chest strap with my Garmin 305, and also one with my Polar F6. The Garmin is always higher...WAY higher, to the tune of 1,000 extra calories. Garmin is known for being high on the caloric expenditure estimation. Polar is the industry standard for accuracy in HRM-based calorie tracking.

tmthorn0927

How do you find out your resting rate?

tmthorn0927

Also, a question do people leave the timer on during weights the whole time or do you stop and start the watch at each set. I leave it running even when I'm resting between each sets. Is this bad? Inaccurate when measuring calories burned in a work out?

Thanks

Anyone?

If I am still working out (weights), I leave it on. I stop my in between cardio activities (treadmill, eliptical, etc.) so I can see what I burn on each machine.

BerryH

How do you find out your resting rate?

Wear your HRM in bed and take it for three days and average it out. If you have to get up to go to the bathroom or put your HRM on, go back to bed and doze off or rest for a bit. It varies on a daily basis hence the average.

erickirb

How do you find out your resting rate?

Wear your HRM in bed and take it for three days and average it out. If you have to get up to go to the bathroom or put your HRM on, go back to bed and doze off or rest for a bit. It varies on a daily basis hence the average.

This will not work, this will overestimate your burn as your HRM assumes you are moving not sleeping when calculating calories burned. It may give you a rough idea, but more than likely will over estimate the burn during sleep.

BerryH

This will not work, this will overestimate your burn as your HRM assumes you are moving not sleeping when calculating calories burned. It may give you a rough idea, but more than likely will over estimate the burn during sleep.

This is exactly the method used by Runner's World and my favourite HRM book "Heart Monitor Training for the Compleat Idiot". It's the basis of the formula for finding your real training zone more accurately.

This from RW:
1. Find your maximum heart rate (see above) eg 206
2. Find your resting heart rate (laying still, soon after you wake up. Ideally take an average over a few days). eg 56
3. Subtract the resting rate from the maximum. This figure is your working heart rate. eg 206-56=150
4. Take whatever percentage of your working heart rate that you’re aiming for (eg 60% for an easy run eg 150x0.60=90), and add it to your resting heart rate eg 90+56=146. The final figure is your personal target heart rate.

http://www.runnersworld.co.uk/general/heart-rate-training---the-basics/176.html

erickirb

This will not work, this will overestimate your burn as your HRM assumes you are moving not sleeping when calculating calories burned. It may give you a rough idea, but more than likely will over estimate the burn during sleep.

This is exactly the method used by Runner's World and my favourite HRM book "Heart Monitor Training for the Compleat Idiot". It's the basis of the formula for finding your real training zone more accurately.

This from RW:
1. Find your maximum heart rate (see above) eg 206
2. Find your resting heart rate (laying still, soon after you wake up. Ideally take an average over a few days). eg 56
3. Subtract the resting rate from the maximum. This figure is your working heart rate. eg 206-56=150
4. Take whatever percentage of your working heart rate that you’re aiming for (eg 60% for an easy run eg 150x0.60=90), and add it to your resting heart rate eg 90+56=146. The final figure is your personal target heart rate.

http://www.runnersworld.co.uk/general/heart-rate-training---the-basics/176.html

Sorry I mis read your post, I though you were saying how to calculate calories burned at rest, my bad. :blushing:

katkins3

I think they work very well.
I only track the cardio calories and leave the weight training calories as "wiggle room" in case I forget to count the splash of milk in my coffee or a slice of tomato on a salad. (My weight training is pretty minor; no more than a half hour and not training to exhaustion).

mom23nuts

Polar FT7 here - and I consider it quite accurate.

Just remember to update your stats if you lose - been caught on that once or twice. It can only work with what you give it - bad input = bad output LOL

i aggree

I have the ft7 too and originally programmed it wrong when it came to my target heat rate zones, so make sure you have everything in there correctly and it should be accurate....more so than the machinges at the gym that WAY over estimate your burn.

marianne_s

I think some HRMs are probably slightly more accurate than others.

i think it depends on how much indiviual info that you have to inout, which increases the level of accuracy.

I wear a KiFit (UK BodyMedia Fit) and I got a cheap HRM - during cardio exercise the HRM was between 30-50 calories higher.

But during circuit/strength training, the HRM recorded 150+ calories more.

So, I would say HRMs are good for cardio - but not so good for strength training.

TrainingWithTonya

Hi, I am not sure if this topic has been done however I am keen on knowing how accurate HRM are? For some reason I feel as if it overestimates your calorie burn which is annoying but thats me making an assumation. Can anyone clarify how accurate it is.

Thanking you in advance

If you've consumed caffeine, allergy medications, asthma medications, smoked, or used any other stimulant, then it will over estimate. For example, I can get my heart rate up to 130 on the treadmill and burn more calories then if I am sitting on the couch and my heart rate is up to 130 because of my asthma medication, but a heart rate monitor will give me the same reading for calories regardless of whether I'm exercising or not just because the heart rate is up. The same is true of someone on beta blockers or other blood pressure or cardiac medicines that lower heart rate. Those people can be pushing it hard on the treadmill and never get their heart rate up so they appear to the treadmill as if they are sitting on the couch doing no extra calorie burning. So, if you are consuming anything that will effect your heart rate, I don't recommend using a HRM to determine calorie burns. If you are not using any medications or consuming caffeine or anything that will effect your heart rate, then they can be a great tool. No form of estimating calories is 100% accurate, though, so use it as a guide, but know that it isn't set in stone.