Same Heart Rate = Same Calorie Burn?

Options
Edit: To clarify, I am talking about the heart rate of the same person, during the same day (same level of physical fitness for activities) for different STEADY STATE CARDIO activities. I know it varies from person to person because we all will have different VO2max and oxygen usage. I know it may also vary in the same person from month to month as you get more fit.

My primary question is whether you are burning the same calories at the same heart rate regardless of the activity as long as it is a continuous cardio type activity. For example, if my heart rate tends to stay about 125 on the elliptical and also 125 when cycling, am I definitely burning the same amount of calories? Taking it one step further....when I crank up the resistance and/or incline but end up going slower and therefore have a similar heart rate, am I burning the same amount? I am very interested in the answers because I have issues with plantar fasciitis and my joints and have found that less incline and biking causes less pain. If I can be confident that I'm burning a similar amount using these alternatives (assuming a similar heart rate means a similar burn rate), I'll feel better about not cranking up the incline or feeling like I have to be doing a harder activity. I know according to the actual equipment readings, it will usually always assume more incline and more resistance creates a higher burn, but I suspect that is only true if you maintain the same speed and intensity, which I tend not to do.

The idea that the calorie burn seems similar based on the intensity I use which keeps me at a similar heart rate is what I have been noticing in my own calorie burns. I currently am using a Bodybugg by Bodymedia (does not measure heart rate but instead uses heat flux and/or motion to determine burn) to help track my calories burned during activity. It seems like I burn a very similar amount of calories while on the elliptical or cycling (the kind with a nice chair to sit in where you constantly are holding the heart rate monitor bars on either side of your hips). I generally do half the workout with the Bodybugg on my arm and half with it on my calf since I have read that it can underestimate on the arm for activities that predominantly are using the lower body. On the elliptical, I tested 10m on the arm and calf at an incline/resistance of 8 and then 6. For the incline/resistance of 8, I got a reading of 70 calories on my arm and 87 on my calf (both over 10m intervals). For the incline/resistance of 6, I got a reading of 71 calories on my arm and 87 on my calf. Basically, it was the same. Now, on the cycling, it got more interesting. For 10m on my arm, it showed only 13 steps (not surprising since I'm holding the heart rate monitor bars, but interesting because it implies that during this time the Bodybugg derived calorie burn primarily from heat flux due to having little motion data) and a calorie burn of 55. On my calf, cycling (still 10m) burned 108 calories while showing 681 steps (meaning the Bodybugg was likely now deriving a larger part of the burn equation from motion).

So, it appears that the overall calorie burn on the elliptical was 157-158 over 20m while it was 163 while cycling for the same time. Basically, this implies the burn is very similar. My heart rate also remained very similar generally staying between 120-130 for both. However, I am a bit concerned that there is a much bigger difference in burn on arm vs. calf for cycling vs. elliptical. For the elliptical it was 70/87 (arms are moving with elliptical) while it was 55/108 for cycling. I am curious if there may be an overestimate in play for the time the Bodybugg is on my calf while cycling. However, since my heart rate stays about the same between the activities, then that probably means my BB is correct and the difference is only down to the amount of arm movement difference between the elliptical and cycling. Additionally, during cycling, do you think there can be more heat coming from your legs than your arms since you are only using your lower body or is heat (calories burned) during activity supposed to be evenly dispersed across your body regardless of which parts are moving?

What are your thoughts?
«1

Replies

  • ladyoflucky13
    ladyoflucky13 Posts: 41 Member
    Options
    Also, I wanted to add that I realize the Bodybugg is not necessarily completely accurate. I am not so much asking about the exact accuracy of the number of calories burned so much as the relation between the calories burned for different activities (which I believe may be strongly correlated by heart rate, but that is what I'm looking for confirmation about).
  • brianpperkins
    brianpperkins Posts: 6,124 Member
    Options
    No, you are not burning the same amount of calories performing different activities at the same heart rate.
  • ladyoflucky13
    ladyoflucky13 Posts: 41 Member
    Options
    No, you are not burning the same amount of calories performing different activities at the same heart rate.
    Can you please explain your reasoning as to why that is so?
  • brianpperkins
    brianpperkins Posts: 6,124 Member
    Options
    Science.


    Heart rate does not determine caloric burn. There are relationships between heart rate and burn for certain activities but they all have different muscle involvement resulting in different burns ... totally different formulae. Walking is biomechanically different from walking which are both different from cycling ... or swimming ... skipping ... boxing ... dancing ... etc.

    If the same heart rate meant the same burn then sex and scary movies would be great calorie burns.


    http://www.myfitnesspal.com/blog/Azdak/view/the-real-facts-about-hrms-and-calories-what-you-need-to-know-before-purchasing-an-hrm-or-using-one-21472
  • DavPul
    DavPul Posts: 61,406 Member
    Options
    No, you are not burning the same amount of calories performing different activities at the same heart rate.
    Can you please explain your reasoning as to why that is so?

    because heart rate =/= calories burned rate. if that was the case Planet Fitness would have a Haunted House section instead of a Cardio section.
  • WalkingAlong
    WalkingAlong Posts: 4,926 Member
    Options
    I agree with Brian but I think for your purposes, you should do the exercise that doesn't hurt that you enjoy (or hate least) that gets your HR where you want it and the calories will be 'close enough'.

    I think you're splitting hairs expecting the Bugg to do much with skin temps and calf vs. arm and all. I know it says it does but I don't believe it. I've had one and I've had other trackers and I think the Bugg gets most of its data from an accelerometer like the rest of them do.

    Does it even say you can use it on your calf and expect good estimates? Or on a bike? I had mine long ago but I think then it expected you to have it on your arm and to manually log cycling.
  • ladyoflucky13
    ladyoflucky13 Posts: 41 Member
    Options
    No, you are not burning the same amount of calories performing different activities at the same heart rate.
    Can you please explain your reasoning as to why that is so?

    because heart rate =/= calories burned rate. if that was the case Planet Fitness would have a Haunted House section instead of a Cardio section.

    I am referring to heart rate solely during steady state cardio activities. I realize heart rate (and heart rate monitor readings) resulting from a scare or other non-cardio activity is not related to calorie burn. I was under the impression the way that heart rate monitors are able to estimate calorie burn during cardio is by taking a persons age, height, weight, estimated VO2max, etc. and guesstimating from there based on heart rate alone (which wouldn't take into account what kind of activity you are doing). Perhaps I am wrong in how a heart rate monitor is estimating the burn in the first place?
  • ladyoflucky13
    ladyoflucky13 Posts: 41 Member
    Options
    Science.


    Heart rate does not determine caloric burn. There are relationships between heart rate and burn for certain activities but they all have different muscle involvement resulting in different burns ... totally different formulae. Walking is biomechanically different from walking which are both different from cycling ... or swimming ... skipping ... boxing ... dancing ... etc.

    If the same heart rate meant the same burn then sex and scary movies would be great calorie burns.


    http://www.myfitnesspal.com/blog/Azdak/view/the-real-facts-about-hrms-and-calories-what-you-need-to-know-before-purchasing-an-hrm-or-using-one-21472

    I realize that heart rate is not a direct measure of calories burned. However, my understanding is that heart rate monitors are generally used to estimate calorie burns because it is difficult to directly measure oxygen consumption in anything other than a lab setting. I do understand there is a different muscle usage depending on activity and that is part of my wondering, but isn't the whole idea of why heart monitors work based on them being able to estimate oxygen usage from your heart rate once it already knows your gender, age, etc.?
  • BondBomb
    BondBomb Posts: 1,781 Member
    Options
    Actually I was wondering the same thing. When I am running or on the elliptical I am 'working' hard. Sweating my butt off, moving fast. However I don't have to exert nearly as much effort as I do on the stairclimber (stairmill). That thing is a killer, heart rate skyrockets. But again it feels like I am not doing the same amount of work.
    Please advise.
  • ladyoflucky13
    ladyoflucky13 Posts: 41 Member
    Options
    If the same heart rate meant the same burn then sex and scary movies would be great calorie burns.

    LOL....I thought the first activity did come with a bit of calorie burn... :laugh:
  • DavPul
    DavPul Posts: 61,406 Member
    Options
    Perhaps I am wrong in how a heart rate monitor is estimating the burn in the first place?

    well...you said "estimating" the burn, so you can't be totally wrong. it's an estimate based on an algorithm that is set based on information that you give it (weight, age, sex, VO2max, etc) and it uses that, along with your heart rate and the assumption that you are performing a steady state cardio activity to make it's best estimate on calorie burn rate. but it's not your "true" rate, just a best guess.

    different things could trigger different heart rates even tho they might burn the same amount of calories. and let's say you started walking hills when you were completely unfit. your HR might go thru the roof and you'll barely be able to breathe. Now you've run several 10ks and you're in much better shape. walking the same hill might barely make your HR go up and you'll breathe normally. the HRM will give you a lower estimate **even tho the exact same amount of energy (calories) are required to up that same hill (assuming you weigh the same).

    TL;DR it's just a guess. it's probably close enough to work with so don't spend a bunch of time worrying if you have your exact burn numbers. they really don't matter that much.
  • ladyoflucky13
    ladyoflucky13 Posts: 41 Member
    Options
    Does it even say you can use it on your calf and expect good estimates? Or on a bike? I had mine long ago but I think then it expected you to have it on your arm and to manually log cycling.

    I don't think there is an official ruling on using it on the calf. However, I have seen a lot of postings by cyclists who use it solely on their calf and claim it gives a much more accurate rate for times when your arms are in a fixed position. Most of the time, they were comparing their Bodybugg burn to a heart rate monitor, though. According to what people seem to be saying here, I am not sure how accurate heart rate monitors actually are, though, if the rate of calorie burn can vary depending on activity even though you have the same heart rate for the same person.
  • brianpperkins
    brianpperkins Posts: 6,124 Member
    Options
    No, you are not burning the same amount of calories performing different activities at the same heart rate.
    Can you please explain your reasoning as to why that is so?

    because heart rate =/= calories burned rate. if that was the case Planet Fitness would have a Haunted House section instead of a Cardio section.

    I am referring to heart rate solely during steady state cardio activities. I realize heart rate (and heart rate monitor readings) resulting from a scare or other non-cardio activity is not related to calorie burn. I was under the impression the way that heart rate monitors are able to estimate calorie burn during cardio is by taking a persons age, height, weight, estimated VO2max, etc. and guesstimating from there based on heart rate alone (which wouldn't take into account what kind of activity you are doing). Perhaps I am wrong in how a heart rate monitor is estimating the burn in the first place?

    Different ACTIVITIES burn different amounts. The way HRMs estimate caloric burn is based on hooking people up to direct calorimeters while monitoring their heart rates. From that data, different formulae emerged.
  • ladyoflucky13
    ladyoflucky13 Posts: 41 Member
    Options
    Perhaps I am wrong in how a heart rate monitor is estimating the burn in the first place?

    well...you said "estimating" the burn, so you can't be totally wrong. it's an estimate based on an algorithm that is set based on information that you give it (weight, age, sex, VO2max, etc) and it uses that, along with your heart rate and the assumption that you are performing a steady state cardio activity to make it's best estimate on calorie burn rate. but it's not your "true" rate, just a best guess.

    different things could trigger different heart rates even tho they might burn the same amount of calories. and let's say you started walking hills when you were completely unfit. your HR might go thru the roof and you'll barely be able to breathe. Now you've run several 10ks and you're in much better shape. walking the same hill might barely make your HR go up and you'll breathe normally. the HRM will give you a lower estimate **even tho the exact same amount of energy (calories) are required to up that same hill (assuming you weigh the same).

    TL;DR it's just a guess. it's probably close enough to work with so don't spend a bunch of time worrying if you have your exact burn numbers. they really don't matter that much.

    I realize over time it may change. I am basically asking if it is reasonably safe to assume for the same person and the same time period (same fitness level, weight, etc. therefore) if the calorie burn of something like cycling and elliptical should be similar if the heart rate is the same. It seems to be the consensus so far that this is not the case. It mystifies me a bit, though, because it seems that would make heart rate monitors quite inaccurate...and I thought they were supposed to be fairly accurate for steady state cardio.
  • brianpperkins
    brianpperkins Posts: 6,124 Member
    Options
    If the same heart rate meant the same burn then sex and scary movies would be great calorie burns.

    LOL....I thought the first activity did come with a bit of calorie burn... :laugh:

    Not really. On average it's well below 100 calories.
  • ladyoflucky13
    ladyoflucky13 Posts: 41 Member
    Options
    No, you are not burning the same amount of calories performing different activities at the same heart rate.
    Can you please explain your reasoning as to why that is so?

    because heart rate =/= calories burned rate. if that was the case Planet Fitness would have a Haunted House section instead of a Cardio section.

    I am referring to heart rate solely during steady state cardio activities. I realize heart rate (and heart rate monitor readings) resulting from a scare or other non-cardio activity is not related to calorie burn. I was under the impression the way that heart rate monitors are able to estimate calorie burn during cardio is by taking a persons age, height, weight, estimated VO2max, etc. and guesstimating from there based on heart rate alone (which wouldn't take into account what kind of activity you are doing). Perhaps I am wrong in how a heart rate monitor is estimating the burn in the first place?

    Different ACTIVITIES burn different amounts. The way HRMs estimate caloric burn is based on hooking people up to direct calorimeters while monitoring their heart rates. From that data, different formulae emerged.

    I do not currently have a heart rate monitor. Are you saying that heart rate monitors have different formula depending on what activity you are doing (of course steady state cardio) and therefore detect what activity you are doing and vary the formula based on that? I had no idea heart rate monitors were that advanced these days.
  • ladyoflucky13
    ladyoflucky13 Posts: 41 Member
    Options
    If the same heart rate meant the same burn then sex and scary movies would be great calorie burns.

    LOL....I thought the first activity did come with a bit of calorie burn... :laugh:

    Not really. On average it's well below 100 calories.

    So worth it. :blushing:
  • brianpperkins
    brianpperkins Posts: 6,124 Member
    Options
    If the same heart rate meant the same burn then sex and scary movies would be great calorie burns.

    LOL....I thought the first activity did come with a bit of calorie burn... :laugh:

    Not really. On average it's well below 100 calories.

    So worth it. :blushing:

    On average ... men burn more.
  • ladyoflucky13
    ladyoflucky13 Posts: 41 Member
    Options
    On average ... men burn more.

    Unfortunately, that's true for everything. Burning more and building muscle easier. I get jealous of my husband sometimes. :smile:
  • DavPul
    DavPul Posts: 61,406 Member
    Options
    Perhaps I am wrong in how a heart rate monitor is estimating the burn in the first place?

    well...you said "estimating" the burn, so you can't be totally wrong. it's an estimate based on an algorithm that is set based on information that you give it (weight, age, sex, VO2max, etc) and it uses that, along with your heart rate and the assumption that you are performing a steady state cardio activity to make it's best estimate on calorie burn rate. but it's not your "true" rate, just a best guess.

    different things could trigger different heart rates even tho they might burn the same amount of calories. and let's say you started walking hills when you were completely unfit. your HR might go thru the roof and you'll barely be able to breathe. Now you've run several 10ks and you're in much better shape. walking the same hill might barely make your HR go up and you'll breathe normally. the HRM will give you a lower estimate **even tho the exact same amount of energy (calories) are required to up that same hill (assuming you weigh the same).

    TL;DR it's just a guess. it's probably close enough to work with so don't spend a bunch of time worrying if you have your exact burn numbers. they really don't matter that much.

    I realize over time it may change. I am basically asking if it is reasonably safe to assume for the same person and the same time period (same fitness level, weight, etc. therefore) if the calorie burn of something like cycling and elliptical should be similar if the heart rate is the same. It seems to be the consensus so far that this is not the case. It mystifies me a bit, though, because it seems that would make heart rate monitors quite inaccurate...and I thought they were supposed to be fairly accurate for steady state cardio.

    but....you seem to be making the case that "inaccurate" means "not what you expected". it could very well be accurate and your expectations were skewed