HRM vs. treadmill burn -huge difference!

BeyondTrouble

Today was my first time on the treadmill with my new HRM ( I just got a polar ft4). It showed a huge difference! My workout was for 30:41 with an average HR of 162 and a max of 192. My HRM says I burned a whopping 338 calories but the treadmill said I only burned 236?

Which should I log as my burn?

Azdak

It's hard to say without know more detail, such as your age, weight, and avg treadmill speed.

Commerical treadmill calorie counts are pretty accurate--they are very accurate for walking, and they tend to overestimate running calories as speed increases.

In this case, I would ascribed the discrepancy to these possibilities:

1. You were "running" at a speed less than 5.0 mph. For the equations that commercial treadmills use to estimate calories (ACSM), 5.0 mph is considered the minimum speed for running. The equations are different for walking or for running. If you run at a speed less than 5 mph, you are working harder than if you were walking, but the treadmill will calculate calories as though you were walking.

2. You have a higher than average maximum HR. If you have such a max HR, and you do not manually adjust the "HRmax" setting on your HRM, the HRM will assume you are working at a higher perecentage of maximum and will apply a higher "intensity factor" to your workout. This means the calories on your HRM will always be overestimated.

3. I don't know how the FT4 sets your fitness level, so it could be overestimating that as well.

4. Did you enter your weight on the treadmill?

Those and other factors can be part of the "equation". Contrary to what most people think, HRMs are not "plug and play" devices when it comes to calorie estimates.

pixiestick

The rule of thumb is to go with your HRM. Commercial treadmills (and in general all cardio machines) are calibrated to the avg. man... so even when you put in age and weight, it doesn't take hormonal factors into consideration. The treadmill is a guess; the HRM has been specifically tuned to your weight, height, gender, age, and it reads your heart rate on a >5 sec interval... so WAY more accurate.

I use my polar HRM (which I love and consider one of my best allies in this journey). I subtract my avg BMR for the time that I exercised (for me it's roughly 1.5 calories a minute) and that end number is closer than anything else I am going to get (unless I go to a professional facility and they hook me up to fancy machines).

Trust your HRM... be smart, but it is a trustworthy tool.

Leeann1979

Heart rate monitor!!! I have the same one as you and love it...I dont trust the machines at all...I used my recumbent bike the other day, and it said I burned 194 calories, but my HRM said 68.....big difference!!

PatriceMG

If you have your HRM set up correctly with your age, height and weight I would go with the HRM. I have found that the equipment is usually way higher than what my HRM states. Your HRM is an ongoing reading and the machines are calculating based only on when you are connected to the sensors on the machine - not nearly as accurate.

Strive2BLean

Heart Rate Monitor

lovechicagobears

Every medical study I've read, where they used lab testing to measure actual calories burned, stated that HRMs can be off by 9% - 13% in women. It was fairly consistent for every brand. So, to be safe, I subtract 20% from my HRM reading.

My HRM is always much, much higher than the treadmill. The treadmill I use doesn't measure my heart rate over time, so it has no way of knowing how long I'm in "the zone". It beeps at me every couple of minutes, checks my heart rate when I put my hands on the bar, and then beeps at me to remove them. That's why I prefer my HRM. I like to see if I need to step it up a notch right away, rather than waiting for the machine.

janf15

No matter what 'gadget' you are using it is not going to be accurate. The only way to get the accurate numbers - get it measured (and you will have to attach $$$ sign) However, what you want to get is a consistent measurement of your caloric spenditure when you do cardio. I am a multi sport athlete (swim, bike, and run - yes that includes triathlons), and I when I use the caloric spenditure - I look at the number on my HRM. That way it is consistent across the disciplines. And again - it still only a rule of thumb. You will NEVER get an accurate caloric spenditure on one of these gizmos. And yes, as the poster said, the accuracy will vary 3- 18 ... 20%. I would not compensate for the incorrectness at all. It doesn't make sense (in my opinion)

drgummibear

Just make sure that your heart rate monitor is set up properly with your current weight and other stats that it may ask for. Most heart rate monitors come set up for an average weight of about 180lbs, for a general reading. But you should go into your settings and change them to reflect accurately your stats. Hope this helps cheers :drinker: drgummibear

Azdak

The rule of thumb is to go with your HRM. Commercial treadmills (and in general all cardio machines) are calibrated to the avg. man... so even when you put in age and weight, it doesn't take hormonal factors into consideration. The treadmill is a guess; the HRM has been specifically tuned to your weight, height, gender, age, and it reads your heart rate on a >5 sec interval... so WAY more accurate.

I use my polar HRM (which I love and consider one of my best allies in this journey). I subtract my avg BMR for the time that I exercised (for me it's roughly 1.5 calories a minute) and that end number is closer than anything else I am going to get (unless I go to a professional facility and they hook me up to fancy machines).

Trust your HRM... be smart, but it is a trustworthy tool.

That's just not true--or at least it hasn't been for at least 20 years. Commercial treadmills (Life Fitness, Precor, Cybex, etc) all allow individual weight input -- in fact Life Fitness treadmills will not give you a calorie reading at all unless you input your weight.

Treadmills measure the actual work you are doing--which is THE most important factor in determining calories burned. Because there is a consistent relationship between treadmill walking speed/elevation and energy expended, it is relatively simple for a treadmill to accurately estimate calories burned when walking (without handrail support). For running, the treadmill will start to overestimate calories burned as speed increases.

HRMs are the devices that are guessing at your effort. HRMs have NO idea what you are doing or your actual exercise workload. They require all of the additional input because they are so imprecise about what they are measuring. HRMs are programmed to spit out a number based on heart rate--and the equations they use are only valid under very specific conditions--steady-state aerobic exercise. Even at their most accurate, they can be easily 15%-20% off--and that's if you have them set up correctly, which most people do not.

Azdak

If you have your HRM set up correctly with your age, height and weight I would go with the HRM. I have found that the equipment is usually way higher than what my HRM states. Your HRM is an ongoing reading and the machines are calculating based only on when you are connected to the sensors on the machine - not nearly as accurate.

That's not true, either. The heart rate sensors on the machines are not involved in any way with calorie estimates.

Machines all use computer circuits to calibrate and monitor workload--any they measure workload continuously as long as the machine is being used.

The fact that the machine calories are different than your HRM calories is not evidence that the machines are wrong.

pixiestick

The rule of thumb is to go with your HRM. Commercial treadmills (and in general all cardio machines) are calibrated to the avg. man... so even when you put in age and weight, it doesn't take hormonal factors into consideration. The treadmill is a guess; the HRM has been specifically tuned to your weight, height, gender, age, and it reads your heart rate on a >5 sec interval... so WAY more accurate.

I use my polar HRM (which I love and consider one of my best allies in this journey). I subtract my avg BMR for the time that I exercised (for me it's roughly 1.5 calories a minute) and that end number is closer than anything else I am going to get (unless I go to a professional facility and they hook me up to fancy machines).

Trust your HRM... be smart, but it is a trustworthy tool.

That's just not true--or at least it hasn't been for at least 20 years. Commercial treadmills (Life Fitness, Precor, Cybex, etc) all allow individual weight input -- in fact Life Fitness treadmills will not give you a calorie reading at all unless you input your weight.

I specifically made the point about gender, not weight. If a treadmill takes "196lbs" as my starting weight, and I am 6'2" man, that is a huge difference than if I am a 5'2" woman. The machine is calibrated to the avg. height of a man and calculates off of that. Some of the more amazing machines will personalize to gender, height, and age, but most (particularly the mass-market models that gyms use) will only take in your weight as a factor.

Treadmills measure the actual work you are doing--which is THE most important factor in determining calories burned. Because there is a consistent relationship between treadmill walking speed/elevation and energy expended, it is relatively simple for a treadmill to accurately estimate calories burned when walking (without handrail support). For running, the treadmill will start to overestimate calories burned as speed increases.

HRMs are the devices that are guessing at your effort. HRMs have NO idea what you are doing or your actual exercise workload. They require all of the additional input because they are so imprecise about what they are measuring. HRMs are programmed to spit out a number based on heart rate--and the equations they use are only valid under very specific conditions--steady-state aerobic exercise. Even at their most accurate, they can be easily 15%-20% off--and that's if you have them set up correctly, which most people do not.

Treadmills only measure the speed/incline, they cannot measure the actual work. How my body actually works 7mph on a 3% incline is completely different then how a much thinner woman's or fitter man's body actually works with those same stats. A treadmill doesn't measure the individual athlete's work. Also, when you jump off the mill for a moment or two to catch your breath, tie your shoe, or drink water, the treadmill is still measuring something... but it's not the athlete's actual work, it is the machine's.

An HRM, like a cardio machine at the gym, is only one tool in the weight loss journey. It just so happens that the former is a more accurate tool than the latter.

Azdak

No matter what 'gadget' you are using it is not going to be accurate. The only way to get the accurate numbers - get it measured (and you will have to attach $$$ sign) However, what you want to get is a consistent measurement of your caloric spenditure when you do cardio. I am a multi sport athlete (swim, bike, and run - yes that includes triathlons), and I when I use the caloric spenditure - I look at the number on my HRM. That way it is consistent across the disciplines. And again - it still only a rule of thumb. You will NEVER get an accurate caloric spenditure on one of these gizmos. And yes, as the poster said, the accuracy will vary 3- 18 ... 20%. I would not compensate for the incorrectness at all. It doesn't make sense (in my opinion)

The problems I have with your method--and I think you have the right philosophy-- is that heart rate can vary so much and be influenced by things that have nothing to do with fitness. Also, if you don't constantly adjust your HRM settings, then it often will not capture performance increases.

Example: I have my HRM set up with my max HR and a VO2 max of 40. I train on an elliptical at various intesity/duration combos. I do a "performance test" to see how many calories I can burn (on the machine) in 45 min and come up with 650. My avg HR is 140, or 80% of max. My HRM calorie reading is close--it says I burned 600 calories. After 4 weeks of training, I repeat the test again. This time I achieve 730 calories in 45 min on the machine. Because my fitness level has improved through training, the avg HR is the same--still 140, or 80% of max. (That's the expected effect of training--to be able to work harder at the same relative intensity).

However, since I did not adjust the VO2 max setting on my HRM, the HRM still tells me I burned 600 calories. Since the machine is measuring actual workload, it reliably shows the improvement (whether or not the actual number itself is accurate--the difference still represents an actual change). The HRM does not show the difference because it only reads heart rate--it has no idea what you were actually DOING to achieve that heart rate.

I am assuming you have been doing this long enough that you have a system that makes sense to you and that's all that counts, but for people using machines, the machine calorie readouts are a much more precise and accurate way to keep track of fitness improvement that either HRM calories or avg HR.

pixiestick

I am assuming you have been doing this long enough that you have a system that makes sense to you and that's all that counts, but for people using machines, the machine calorie readouts are a much more precise and accurate way to keep track of fitness improvement that either HRM calories or avg HR.

It is apparent that you are well versed in this world of fitness and measuring effort, so I am not doubting that you have your reasons. I also do not deny that HRMs are not 100% accurate (and can be dramatically off on some people). What I don't understand is the claim that one machine which is strapped to the individual and getting a read directly from that athlete's heart is LESS accurate than a machine which has no idea how difficult the activity being completed is for the specific individual.

I am puzzled by your logic as I have not heard it before.

Azdak

The rule of thumb is to go with your HRM. Commercial treadmills (and in general all cardio machines) are calibrated to the avg. man... so even when you put in age and weight, it doesn't take hormonal factors into consideration. The treadmill is a guess; the HRM has been specifically tuned to your weight, height, gender, age, and it reads your heart rate on a >5 sec interval... so WAY more accurate.

I use my polar HRM (which I love and consider one of my best allies in this journey). I subtract my avg BMR for the time that I exercised (for me it's roughly 1.5 calories a minute) and that end number is closer than anything else I am going to get (unless I go to a professional facility and they hook me up to fancy machines).

Trust your HRM... be smart, but it is a trustworthy tool.

That's just not true--or at least it hasn't been for at least 20 years. Commercial treadmills (Life Fitness, Precor, Cybex, etc) all allow individual weight input -- in fact Life Fitness treadmills will not give you a calorie reading at all unless you input your weight.

I specifically made the point about gender, not weight. If a treadmill takes "196lbs" as my starting weight, and I am 6'2" man, that is a huge difference than if I am a 5'2" woman. The machine is calibrated to the avg. height of a man and calculates off of that. Some of the more amazing machines will personalize to gender, height, and age, but most (particularly the mass-market models that gyms use) will only take in your weight as a factor.

Treadmills measure the actual work you are doing--which is THE most important factor in determining calories burned. Because there is a consistent relationship between treadmill walking speed/elevation and energy expended, it is relatively simple for a treadmill to accurately estimate calories burned when walking (without handrail support). For running, the treadmill will start to overestimate calories burned as speed increases.

HRMs are the devices that are guessing at your effort. HRMs have NO idea what you are doing or your actual exercise workload. They require all of the additional input because they are so imprecise about what they are measuring. HRMs are programmed to spit out a number based on heart rate--and the equations they use are only valid under very specific conditions--steady-state aerobic exercise. Even at their most accurate, they can be easily 15%-20% off--and that's if you have them set up correctly, which most people do not.

Treadmills only measure the speed/incline, they cannot measure the actual work. How my body actually works 7mph on a 3% incline is completely different then how a much thinner woman's or fitter man's body actually works with those same stats. A treadmill doesn't measure the individual athlete's work. Also, when you jump off the mill for a moment or two to catch your breath, tie your shoe, or drink water, the treadmill is still measuring something... but it's not the athlete's actual work, it is the machine's.

An HRM, like a cardio machine at the gym, is only one tool in the weight loss journey. It just so happens that the former is a more accurate tool than the latter.

Speed/Incline IS the work--that's the ONLY relevant measurement. The amount of physical work performed during walking on a treadmill can be measured fairly easily and the prediction equations have been validated for decades. In the scientific community, this is not an area of dispute.

Individual variations in gait and mechanical efficiency start to occur at speeds less than 2.0 mph and greater than 4.2 mph for walking, which is why the equations are not considered valid outside of that speed range.

However, actual work performed is not dependant on age, gender, or fitness level for the most part. Two people walking 3.5 mph on a treadmill will do the same amount of aerobic work -- approx 3.6 METs--regardless of age, gender, or fitness level. The heavier person will burn more calories, and the more fit person will be able to do the work more easily, but the actual measured work will be the same.

I know people have a lot of "faith investment" in their HRMs and have trouble accepting their limitations. I just try to provide the facts so that people can make the best decisions for themselves.

Azdak

I changed my mind.

pixiestick

If the metabolic equivalent is what you are using to base this assertion of cardio machine>HRM, then I feel comfortable agreeing to disagree. One doesn't have to go very far to find that using METs as a measurement for individual effort is highly problematic as the calculation is based off of an average (my original point of contention). You don't need to go very far to find this issue is hotly debated.

The HRM is not fool proof. I advised that the OP be smart when using the calculations she got (I subtract my BMR expenditure). However, it is a better tool, as it is based on the individual, than taking the reading off of a machine.

I know people have a lot of "faith investment" in their HRMs and have trouble accepting their limitations. I just try to provide the facts so that people can make the best decisions for themselves.

Any time we attempt to calculate our own bodies, there is a certain degree of "faith investment"; MRI's, CAT scans, X-rays, to some extent, are a faith investment to understand the the perplexities of the human body. Using the tool which most closely personalizes my information to my body seems to be the safest investment; using the cardio machine, calibrated to a body that is not my own, seems to involve a lot more "faith" than I am comfortable with.

BeyondTrouble

I was afraid that it wouldn't be an easy answer

I know that my max HR seems high, but I only just started working out and this is basically my week one. I'm 32 years old, 5'5 and 213.6 pounds - (I started at 217.2 last Sun). MPF suggested 1200 calories but that was just too little - so I've put myself at just under 1400. It's a doable amount and I'm less likely to bail and retreat from trying to get all this extra weight off.

Would my max HR be high due to quitting smoking two months ago? I was a heavy smoker for 13 years and quit cold turkey. So I'm thinking the answer might be yes

I did enter my stats into the polar ft4 and I was doing the C25k program where I walked around 3.2 and ran between 4.8-5.0 mph. Yes, I entered my weight on the treadmill as well.

Anyway, I've been eating back some if not all of my workout calories so I really wanted to make sure I wasn't going overboard. It sounds like I should hold back from consuming ALL of them since the HRM isn't totally accurate.

If I'm wrong, or you have further suggestion please keep 'em coming! Thank you to all who responded!

heybales

Oh Azdak, I missed all the fun.

http://www.myfitnesspal.com/topics/show/773451-is-my-hrm-giving-me-incorrect-calorie-burn

http://www.myfitnesspal.com/topics/show/774337-how-to-test-hrm-for-how-accurate-calorie-burn-is

For those that think the HRM is more accurate than the treadmill, look at the accuracy in that second link.

heybales

I know that my max HR seems high, but I only just started working out and this is basically my week one. I'm 32 years old, 5'5 and 213.6 pounds - (I started at 217.2 last Sun). MPF suggested 1200 calories but that was just too little - so I've put myself at just under 1400. It's a doable amount and I'm less likely to bail and retreat from trying to get all this extra weight off.

Would my max HR be high due to quitting smoking two months ago? I was a heavy smoker for 13 years and quit cold turkey. So I'm thinking the answer might be yes

I did enter my stats into the polar ft4 and I was doing the C25k program where I walked around 3.2 and ran between 4.8-5.0 mph. Yes, I entered my weight on the treadmill as well.

Anyway, I've been eating back some if not all of my workout calories so I really wanted to make sure I wasn't going overboard. It sounds like I should hold back from consuming ALL of them since the HRM isn't totally accurate.

If I'm wrong, or you have further suggestion please keep 'em coming! Thank you to all who responded!

Your HRmax is genetically set basically. There is no seems high or not. Mine tested is what would be calculated for a 26 yr old, not my 44, I'm 18 bpm higher that normal calc's. But a gym spin instructor is 10 yrs older than me, but has a 10 bpm slower than expected, but super fit too.

Going from no exercise to exercise will effect your ability to hit it and make it easier, but it's pretty much set. The smoking again effects ability to hit it.

Some have Honda high HRmax hearts, some have diesel low HRmax hearts. Just different. Hence the reason that stat is important.

If you've been exercising it stays about the same level, if you started later in life in usually declines as you age.

BTW, for your speeds - the treadmill was more accurate.

The FT4 is missing a stat that allows it to keep up with your improving fitness. It is basing that stat instead on your BMI, assuming the more you weigh, the less fit you are. Which may in general be true, but it won't know about your big gains in fitness you get immediately while your weight may not change much.

So get the HRmax figured out. The spreadsheet on the HRM tab has several simple self-tests to estimate, and other formula's.
Or just use the HRM to get your avgHR and time for a session, fill in the stats there, and use your personal burn table at the bottom of that tab based on a Polar funded study formula that is using HRmax, VO2max (that's the missing stat), and your specifics.
I'll bet it matches up with the treadmill better.

honeyallen

according to my view, HRM is reading the correct heart rates, but too many calories. But, I don't know what you weight, and need to know more about your run/walk scheme to make anything more than that qualitative judgement. Professional grade treadmills (like at most gyms) are usually more accurate than the type of HRM that you are using (but treadmills do have problems in certain speed ranges). I believe that they are more accurate when used in an "incline walk" mode rather than running on the flat (less variability between people than in running).