heart rate monitor vs excerise "calories"

lfegen
lfegen Posts: 2 Member
edited September 19 in Fitness and Exercise
I have noticed my heart rate monitor registers my calories burned much lower then when you enter s specific excercise and time on this site...for example: I did a recovery ride at 16.1 mph for 1 hour..my hr monitor registers 511 cals burned, but when you enter that number based on the moderate cycling entry it says I burned 650 or something....my monitor is accurate and set to my specific weight, height..etc..I end up having to reduce the time on the entry to get the cals to match up.

Any idea why that is...granted I dont use the excercise portion to track my fitness..use excel for that.

Replies

  • lfegen
    lfegen Posts: 2 Member
    I have noticed my heart rate monitor registers my calories burned much lower then when you enter s specific excercise and time on this site...for example: I did a recovery ride at 16.1 mph for 1 hour..my hr monitor registers 511 cals burned, but when you enter that number based on the moderate cycling entry it says I burned 650 or something....my monitor is accurate and set to my specific weight, height..etc..I end up having to reduce the time on the entry to get the cals to match up.

    Any idea why that is...granted I dont use the excercise portion to track my fitness..use excel for that.
  • lyla29
    lyla29 Posts: 3,549 Member
    your hrm is the one that is accurate. this site uses averages for calories burned. When you add your exercise, you can manually enter the number of calories that your hrm says you burned instead of changing the minutes that you exercised.:smile:
  • nickybr38
    nickybr38 Posts: 674 Member
    your hrm is the one that is accurate. this site uses averages for calories burned. When you add your exercise, you can manually enter the number of calories that your hrm says you burned instead of changing the minutes that you exercised.:smile:

    Actually you can change both minutes you exercised and how many calories burned. :)
  • lunglady
    lunglady Posts: 526 Member
    Work = force x distance. ( check a physics textbook if you don't believe me)

    The exercise machine is more accurate, because it is actually measuring work. Calories (you can convert from joules) is the unit used to measure work.

    Heart rate monitors do not actually measure the work that you are doing. It is a component of your physiologic response to work, which is dependent on many variables, including your level of fitness. If two subjects, one deconditioned, and the second fit, walked he same distance over the same terrain, they would burn the same amount of calories, although the fit person would have a lower heart rate. This has to do with a more efficient heart with a higher stroke volume (more blood pumped per beat), thus necessitating fewer beats per minute to deliver the same amount of tissue to the muscles.

    In addition, there are medications which affect heart rate. For example, a person taking B-blockers may not be able to mount a tachycardic response to exercise, even though they are doing the same amount of work. This does not make the amount of work they die (ie: calorie burnes) any less.

    I hope this helps.

    J. Coleman, MD
  • Chellekk
    Chellekk Posts: 421 Member
    Work = force x distance. ( check a physics textbook if you don't believe me)

    The exercise machine is more accurate, because it is actually measuring work. Calories (you can convert from joules) is the unit used to measure work.

    Heart rate monitors do not actually measure the work that you are doing. It is a component of your physiologic response to work, which is dependent on many variables, including your level of fitness. If two subjects, one deconditioned, and the second fit, walked he same distance over the same terrain, they would burn the same amount of calories, although the fit person would have a lower heart rate. This has to do with a more efficient heart with a higher stroke volume (more blood pumped per beat), thus necessitating fewer beats per minute to deliver the same amount of tissue to the muscles.

    In addition, there are medications which affect heart rate. For example, a person taking B-blockers may not be able to mount a tachycardic response to exercise, even though they are doing the same amount of work. This does not make the amount of work they die (ie: calorie burnes) any less.

    I hope this helps.

    J. Coleman, MD

    So, you're in turn saying:

    Joe Schmoe who's 100 pounds and phsically fit
    VS
    Joe Schmoe who's 300 pounds and NOT fit (Or vise versa)

    will burn the same amount of calories if they both run a mile??

    For some reason I don't think this is correct. Everyone is different and would burn a different amount. NO? Just a thought and a good topic to share.
  • jadaigle
    jadaigle Posts: 161 Member
    I think your weight factors into calories burned.
  • lunglady
    lunglady Posts: 526 Member
    Your gait factors into it, but if they walked in exactly the same way, then yes, they would burn the same # of calories.

    Heart rate is NOT a unit of work, calories are. There is no consistent way to convert heart rate into calories (units of work). the heart rate response to exercise id dependent upon multiple physiologic variables.

    When we do exercise studies at the hospital (I'm a pulmonologist), we use a cycle ergotomer instead of a treadmill so that we can standardize the amount of external work (this takes weight out of the equation). If we set the cycle to the same resistance and have them cycle at the same rpm, then both Joes are doing the SAME amount of work, although 300lb Joe will have a higher heart rate.

    J. Coleman, MD
  • Renae_Nae
    Renae_Nae Posts: 935 Member
    Your gait factors into it, but if they walked in exactly the same way, then yes, they would burn the same # of calories.

    Heart rate is NOT a unit of work, calories are. There is no consistent way to convert heart rate into calories (units of work). the heart rate response to exercise id dependent upon multiple physiologic variables.

    When we do exercise studies at the hospital (I'm a pulmonologist), we use a cycle ergotomer instead of a treadmill so that we can standardize the amount of external work (this takes weight out of the equation). If we set the cycle to the same resistance and have them cycle at the same rpm, then both Joes are doing the SAME amount of work, although 300lb Joe will have a higher heart rate.

    J. Coleman, MD

    Do you have any articles or anything to back that up? I have ALWAYS heard that two people who are different weight will burn a different amount of calories. If not then why do heavier people lose weight so much faster? Is it not because they are carrying the extra weight around in everyday activities and are burning more calories because of it?
  • lunglady
    lunglady Posts: 526 Member
    You can consult any physics textbook to understand what a calorie is and what it measures. It's important to understand what "work" really is.

    For exercise physiology, I prefer Wasserman's " Principle's of Exercise Testing and Interpretation". Probably not available at your local library but if you live near a medical school you might be in luck.

    Happy reading :flowerforyou:
  • ivykivy
    ivykivy Posts: 2,970 Member
    You can consult any physics textbook to understand what a calorie is and what it measures. It's important to understand what "work" really is.

    For exercise physiology, I prefer Wasserman's " Principle's of Exercise Testing and Interpretation". Probably not available at your local library but if you live near a medical school you might be in luck.

    Happy reading :flowerforyou:

    I think I understand what you are saying is the heart rate monitor assumes that if you have a heart rate of x that you are doing y amount of work. However different factors (you listed medication) can affect what that heart rate is so it is not necesarily a good indicator of how much work you are doing.

    The exercise machine is calculating the calories based on W=F*D or W= Mass x acceleration *distance. So if you input your weight it is more accurate that the HRM?
  • lunglady
    lunglady Posts: 526 Member
    Exactly!!! :flowerforyou:
  • Rae22
    Rae22 Posts: 10
    I have noticed that too. But, I leave my monitor on until I get home from the gym. So those extra 100 or so calories I burned after I was done working out do not count either.
    But you can change the calorie amount also.
  • Chellekk
    Chellekk Posts: 421 Member
    You can consult any physics textbook to understand what a calorie is and what it measures. It's important to understand what "work" really is.

    For exercise physiology, I prefer Wasserman's " Principle's of Exercise Testing and Interpretation". Probably not available at your local library but if you live near a medical school you might be in luck.

    Happy reading :flowerforyou:

    I think I understand what you are saying is the heart rate monitor assumes that if you have a heart rate of x that you are doing y amount of work. However different factors (you listed medication) can affect what that heart rate is so it is not necesarily a good indicator of how much work you are doing.

    The exercise machine is calculating the calories based on W=F*D or W= Mass x acceleration *distance. So if you input your weight it is more accurate that the HRM?

    Which is why I would assume that even on a bike machine you would enter your weight, so it would tell you that yes, Joe weighing more, is actually burning more calories.
  • jsmccloy
    jsmccloy Posts: 59 Member
    Science geek time!
    work done does = force x distance, but 300 lb. Joe Shmoe has to apply more force to move the extra weight when running a mile, so 300 lb. Joe Shmoe would do three times as much work as 100 lb. Joe FitShmoe.
    However, on an exercise bike a lot of the weight factor is taken out of the equation, as both Joes push against a set resistance instead of lifting their bodies (assuming both Joes ride in a seated position).

    But pumping the pedals is not the only work done on the exercise bike. Calories are a measure of energy, and that energy can also be in the form of heat. 300 lb Joe Shmoe produces a lot more heat while riding the bike than 100 lb. Joe Fitshmoe. That heat is produced by the burning of calories. Calories a burnt and heat is produced by the pumping of the heart, the flexing of the muscles, the dilating of blood vessels, the increased use of the diaphragm as you breathe heavier, etc.
    :yawn: Still with me?
    So, what MFP tells you are the calories burnt, what the exercise equipment tells you, and what the HRM tells you are all going to be estimates, since none of them can measure every factor.
    For myself I just make sure I have my base calories and then lowball my exercise calories in hopes of being happily surprised on measuring day :happy:
  • this is a fascinating discussion...
    I have been thinking about getting a HRM for use in the gym and to help track my fitness progress. I'm woefully out of shape and happen to be a data nerd, so I figure the more data I have about my progress the more to motivate me to continue.

    I'm wondeirng now if a HRM is really a wise investment, if I should really be using the machine calculations. Another thing that I have noticed is that different machines give you a different answer even though you exercise at roughly the same pace and for the same distance/time. I don't understand that either.

    Would love more info... :)



    119263.png
    Created by MyFitnessPal.com - Free Food Diary
  • Chellekk
    Chellekk Posts: 421 Member
    this is a fascinating discussion...
    I have been thinking about getting a HRM for use in the gym and to help track my fitness progress. I'm woefully out of shape and happen to be a data nerd, so I figure the more data I have about my progress the more to motivate me to continue.

    I'm wondeirng now if a HRM is really a wise investment, if I should really be using the machine calculations. Another thing that I have noticed is that different machines give you a different answer even though you exercise at roughly the same pace and for the same distance/time. I don't understand that either.

    Would love more info... :)



    119263.png
    Created by MyFitnessPal.com - Free Food Diary

    I've been testing my HRM this week and have been comparing the read out to what I've found and have been using on MFP since mid-Nov. Some are roughly the same, some are not. It's hard to tell what LIGHT, MODERATE and VIGOROUS mean to each individual's work out style.

    MFP = 60 min of soccer (general, casual) has me burning 553 cal. I run my bu tt off during the games and thought this was a good number. My HRM on Monday said I burned 776. I then took out my REST HR of aprox 70 which left me at 706. I think this is more accurate, cause I have NEVER run this hard in my life. I know it's no longer "casual".

    MFP = 40 min stationary bike (moderate effort) has me burning 349 cal. Last night I wore my HRM and got on my bike, which is a road bike on an indoor trainer, and in 40 min I burned 352 minus my rest rate left me at 320. Lower. Not by much, but lower.

    I think it's best to get a HRM because MFP is just an estimate. Based on your height, weight, age, you may be burning more or less. Just me 2 cents. :smile:
  • Chellekk
    Chellekk Posts: 421 Member
    Oh...and volleyball Tuesday...

    MFP = 60 minutes (only two options for standard VB, non-competitive 6-9 member team or competitive) has me burning either 229 or 610 calories. My HRM said 440 minus rest rate 70 = 370.
  • runnerdad
    runnerdad Posts: 2,081 Member
    this is a fascinating discussion...
    I have been thinking about getting a HRM for use in the gym and to help track my fitness progress. I'm woefully out of shape and happen to be a data nerd, so I figure the more data I have about my progress the more to motivate me to continue.

    I'm wondeirng now if a HRM is really a wise investment, if I should really be using the machine calculations. Another thing that I have noticed is that different machines give you a different answer even though you exercise at roughly the same pace and for the same distance/time. I don't understand that either.

    Would love more info... :)

    I would still get the HRM, both to monitor the intensity of your work outs and measure your recovery after your work out. If your goal is weight loss / general fitness, you will lose weight more efficiently working in an aerobic range of heart heart, so your HRM will tell you when you're overdoing it (or not pushing hard enough). The rate of recovery to your resting HR is a good indication of fitness, so continue to monitor HR when you are finished your work out to track your improvement in fitness.

    My beef on the calorie calculations from your heart rate monitor is when I read posts from people who get on an elliptical machine and put their heart rate through the roof, then get off and sit on the floor to stretch and think they're still burning a ton of calories while stretching ( or driving home from the gym) because their HR stays elevated, when in fact it is really an indication that they aren't fit enough to recover from their work out in a timely manner.

    Of course, the calorie count on the machine assumes you are actually doing the work on the machine. Every time I go to the gym, you see people (you know who you are) on the treadmill with the incline and the speed cranked up, and they have their upper body draped over the console to hold themselves up and their legs are just flailing free because they can't keep up with the pace. Obviously, they are not burning the same calories as they would if they let go and actually worked hard enough to avoid getting flung off the back! (The same is true for all you people on the ellipticals who brace your arms on the side rails to take your weight off your legs - hello - isn't that the point of being there?):tongue:
  • ivykivy
    ivykivy Posts: 2,970 Member
    I read that each treadmill maker uses a different formula to tell you how many calories are burned. But usually the differences is only 10 percent. When I input my exercise I usually shave off 20-25%. So if I do 45 min of Taebo I count it as 30 judo karate.

    The key is whatever keeps you motivated. So if you think an HRM will keep you motivated get one. If you can be satisfied with using the calculators that is good too. The only thing I have heard people say is if you get an HRM get a quality one.
    this is a fascinating discussion...
    I have been thinking about getting a HRM for use in the gym and to help track my fitness progress. I'm woefully out of shape and happen to be a data nerd, so I figure the more data I have about my progress the more to motivate me to continue.

    I'm wondering now if a HRM is really a wise investment, if I should really be using the machine calculations. Another thing that I have noticed is that different machines give you a different answer even though you exercise at roughly the same pace and for the same distance/time. I don't understand that either.

    Would love more info... :)



    119263.png
    Created by MyFitnessPal.com - Free Food Diary
  • ivykivy
    ivykivy Posts: 2,970 Member
    I think what she is saying is they take weight out of the equation because weight composition is a factor also. Two 200 lb people will not burn the same amount of calories if one has 50% body fat and one has 10%. That is why they always tell you exercise calculators are not accurate for the very obese or very muscular or short or tall or people in people in high elevation or very hot places..:wink:


    You can consult any physics textbook to understand what a calorie is and what it measures. It's important to understand what "work" really is.

    For exercise physiology, I prefer Wasserman's " Principle's of Exercise Testing and Interpretation". Probably not available at your local library but if you live near a medical school you might be in luck.

    Happy reading :flowerforyou:

    I think I understand what you are saying is the heart rate monitor assumes that if you have a heart rate of x that you are doing y amount of work. However different factors (you listed medication) can affect what that heart rate is so it is not necesarily a good indicator of how much work you are doing.

    The exercise machine is calculating the calories based on W=F*D or W= Mass x acceleration *distance. So if you input your weight it is more accurate that the HRM?

    Which is why I would assume that even on a bike machine you would enter your weight, so it would tell you that yes, Joe weighing more, is actually burning more calories.
  • lunglady
    lunglady Posts: 526 Member
    I'm really glad to see that I'm not the only true geek (albeit, a cool one) out there.:laugh:
  • SherryRH
    SherryRH Posts: 810 Member
    Your gait factors into it, but if they walked in exactly the same way, then yes, they would burn the same # of calories.

    Heart rate is NOT a unit of work, calories are. There is no consistent way to convert heart rate into calories (units of work). the heart rate response to exercise id dependent upon multiple physiologic variables.

    When we do exercise studies at the hospital (I'm a pulmonologist), we use a cycle ergotomer instead of a treadmill so that we can standardize the amount of external work (this takes weight out of the equation). If we set the cycle to the same resistance and have them cycle at the same rpm, then both Joes are doing the SAME amount of work, although 300lb Joe will have a higher heart rate.

    J. Coleman, MD

    Soooo, would my nike + be a better guide for calories burned when I run vs. my hrm? Just so you know I hate math and this discussion caused my eyes to glaze over as I was reading. :embarassed:
  • altazin0907
    altazin0907 Posts: 188 Member
    Work = force x distance. ( check a physics textbook if you don't believe me)

    The exercise machine is more accurate, because it is actually measuring work. Calories (you can convert from joules) is the unit used to measure work.

    Heart rate monitors do not actually measure the work that you are doing. It is a component of your physiologic response to work, which is dependent on many variables, including your level of fitness. If two subjects, one deconditioned, and the second fit, walked he same distance over the same terrain, they would burn the same amount of calories, although the fit person would have a lower heart rate. This has to do with a more efficient heart with a higher stroke volume (more blood pumped per beat), thus necessitating fewer beats per minute to deliver the same amount of tissue to the muscles.

    In addition, there are medications which affect heart rate. For example, a person taking B-blockers may not be able to mount a tachycardic response to exercise, even though they are doing the same amount of work. This does not make the amount of work they die (ie: calorie burnes) any less.

    I hope this helps.

    J. Coleman, MD

    wow, I have never looked at it that way. I think I agree with you and really trust in what you have to say. Thanks for sharing and would love to hear more about what you know referencing weight loss.
  • Hannah_Banana
    Hannah_Banana Posts: 1,242 Member
    Science geek time!
    work done does = force x distance, but 300 lb. Joe Shmoe has to apply more force to move the extra weight when running a mile, so 300 lb. Joe Shmoe would do three times as much work as 100 lb. Joe FitShmoe.
    However, on an exercise bike a lot of the weight factor is taken out of the equation, as both Joes push against a set resistance instead of lifting their bodies (assuming both Joes ride in a seated position).

    But pumping the pedals is not the only work done on the exercise bike. Calories are a measure of energy, and that energy can also be in the form of heat. 300 lb Joe Shmoe produces a lot more heat while riding the bike than 100 lb. Joe Fitshmoe. That heat is produced by the burning of calories. Calories a burnt and heat is produced by the pumping of the heart, the flexing of the muscles, the dilating of blood vessels, the increased use of the diaphragm as you breathe heavier, etc.
    :yawn: Still with me?
    So, what MFP tells you are the calories burnt, what the exercise equipment tells you, and what the HRM tells you are all going to be estimates, since none of them can measure every factor.
    For myself I just make sure I have my base calories and then lowball my exercise calories in hopes of being happily surprised on measuring day :happy:

    I do the same (lowballing calories burned) but great explanation. :bigsmile:
  • I don't have an HRM, but if I did it would be quite useful. I don't really know how many calories I burn either....I have to rely on this!
  • mommachag
    mommachag Posts: 318
    :love: :love: :love: i love this thread:love::love: :love:
This discussion has been closed.