Losing faith in HR monitor for calories burnt

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  • tincanonastring
    tincanonastring Posts: 3,944 Member
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    MKEgal wrote: »
    Why are you concerned with how many calories you've burned?
    Exercise is for fitness, not weight loss.
    Weight loss happens by eating less.

    If you've eaten the calories you should (the amount to support your weight - 100 to 500)
    and you're really hungry at the end of the day, have a snack of a couple hundred calories, maybe
    1/4 to 1/3 of the most conservative estimate of what you've burned that day.
    If you're consistently losing weight faster than is healthy, adjust your calorie goal slightly.

    You're aware the whole idea of this site is to ensure that, assuming you want to lose weight, calories in must be < calories out? Given that, it's important to know the calories out. I don't really want to have a huge deficit for any given day, so I would rather have some idea of how many calories I've burnt.

    I'm always hungry so I find it hard to use this as a measure of how much food I should eat! Plus, I've read articles suggesting that cyclists tend to over estimate calories burnt on a ride and overeat, and I don't want to do that.

    +1 My broken sense of hunger is why I'm here in the first place!
  • ConicalFern
    ConicalFern Posts: 121 Member
    edited February 2016
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    HR monitors are only accurate as an estimate for steady state cardio. While a bike ride could be steady state, I know in my rides there is a fair amount of variation due to the fact that there are hills, valleys, wind, and even changes in road surface. All of that makes it less true steady state. Add to that the inevitable HR drift that comes from long periods of time spent at an exercise activity which will skew the results, and the HR calorie estimate gets less and less accurate.

    Sorry no - newer HR monitors using variance in HR analysis are as closer to energy use for non-stready state cardio including lifestyle activity. See the FirstBeat research for this. They report a maximal error of 7-10%.

    Also, wasn't the issue with non-steady state cardio that you would get overinflated estimates due to the HR going up and down?

    OP, I'd hardly call 1678 feeble.
    Personally, I err on the side of caution and go with the lower one. If you really want, split the difference.

    I was thinking this as well. That's about 450 calories per hour.

    Then again, the METS value for cycling that fast is 12, which would be way more than 450 calories per hour.

    Are you sure you went that far? That's 18mph for almost 4 hours. :o

    Cycling is my main sport that I've done for most of my adult life, so.. yes :). Plus the Garmin has GPS for distance etc. Average speed for the ride was 17.6.
  • ConicalFern
    ConicalFern Posts: 121 Member
    edited February 2016
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    .
  • sijomial
    sijomial Posts: 19,811 Member
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    MKEgal wrote: »
    Why are you concerned with how many calories you've burned?
    Exercise is for fitness, not weight loss.
    Weight loss happens by eating less.

    If you've eaten the calories you should (the amount to support your weight - 100 to 500)
    and you're really hungry at the end of the day, have a snack of a couple hundred calories, maybe
    1/4 to 1/3 of the most conservative estimate of what you've burned that day.
    If you're consistently losing weight faster than is healthy, adjust your calorie goal slightly.

    @MKEgal

    Not everyone on this site is massively overweight and inactive - or even seeking to lose weight.
    Cyclists in particular can have very high calorie burns which they need to make allowance for.
  • brianpperkins
    brianpperkins Posts: 6,124 Member
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    Firstbeat is helping improve accuracy for non steady state activity but HRMs still are not accurate calorie counters.
  • WalkingAlong
    WalkingAlong Posts: 4,926 Member
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.
  • 3dogsrunning
    3dogsrunning Posts: 27,167 Member
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.

    I worry about my intake at that level of activity because I don't want to undereat.
  • ConicalFern
    ConicalFern Posts: 121 Member
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.

    I can eat a lot I guess... I ate 410 calories on the ride, plus a breakfast that was probably 300 calories bigger than I would normally have, plus 270 when I came in for recovery, which totals to 980 extra calories consumed already. If we're going with the lower estimate that 'only' gives me 698 calories for the ride, which isn't a great deal more than I might burn in a big gym session, but a bike ride makes me a lore more hungry, so I have to be careful.
  • WalkingAlong
    WalkingAlong Posts: 4,926 Member
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.

    I worry about my intake at that level of activity because I don't want to undereat.

    The OP said he didn't want to overeat. I can see it both ways. It just seems like if you can do that sort of athletic feat, I figure you must be Superman, and Superman should be able to eat freely without calcing out his burns and measuring his food. Clearly I'm no Superman, and not around many! ;)
  • 3dogsrunning
    3dogsrunning Posts: 27,167 Member
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.

    I worry about my intake at that level of activity because I don't want to undereat.

    The OP said he didn't want to overeat. I can see it both ways. It just seems like if you can do that sort of athletic feat, I figure you must be Superman, and Superman should be able to eat freely without calcing out his burns and measuring his food. Clearly I'm no Superman, and not around many! ;)

    I also don't want to overeat but I want to eat enough to support training and to lose a bit of weight.
    I haven't done too many 4 hour rides, but I still counted when I did.
  • tincanonastring
    tincanonastring Posts: 3,944 Member
    edited February 2016
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.

    I worry about my intake at that level of activity because I don't want to undereat.

    The OP said he didn't want to overeat. I can see it both ways. It just seems like if you can do that sort of athletic feat, I figure you must be Superman, and Superman should be able to eat freely without calcing out his burns and measuring his food. Clearly I'm no Superman, and not around many! ;)

    I also don't want to overeat but I want to eat enough to support training and to lose a bit of weight.
    I haven't done too many 4 hour rides, but I still counted when I did.

    I was so mad when I blew through my calories after running a half. I finished the run and thought I could eat for days without blowing through that burn. Lolz.
  • 3dogsrunning
    3dogsrunning Posts: 27,167 Member
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.

    I worry about my intake at that level of activity because I don't want to undereat.

    The OP said he didn't want to overeat. I can see it both ways. It just seems like if you can do that sort of athletic feat, I figure you must be Superman, and Superman should be able to eat freely without calcing out his burns and measuring his food. Clearly I'm no Superman, and not around many! ;)

    I also don't want to overeat but I want to eat enough to support training and to lose a bit of weight.
    I haven't done too many 4 hour rides, but I still counted when I did.

    I was so mad when I blew through my calories after running a half. I finished the run and thought I could eat for days without blowing through that burn. Lolz.

    hWIZHzO.webm

    BTDT too.
  • ConicalFern
    ConicalFern Posts: 121 Member
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.

    I worry about my intake at that level of activity because I don't want to undereat.

    The OP said he didn't want to overeat. I can see it both ways. It just seems like if you can do that sort of athletic feat, I figure you must be Superman, and Superman should be able to eat freely without calcing out his burns and measuring his food. Clearly I'm no Superman, and not around many! ;)

    I also don't want to overeat but I want to eat enough to support training and to lose a bit of weight.
    I haven't done too many 4 hour rides, but I still counted when I did.

    I was so mad when I blew through my calories after running a half. I finished the run and thought I could eat for days without blowing through that burn. Lolz.

    How many was that?
  • rileysowner
    rileysowner Posts: 8,228 Member
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    HR monitors are only accurate as an estimate for steady state cardio. While a bike ride could be steady state, I know in my rides there is a fair amount of variation due to the fact that there are hills, valleys, wind, and even changes in road surface. All of that makes it less true steady state. Add to that the inevitable HR drift that comes from long periods of time spent at an exercise activity which will skew the results, and the HR calorie estimate gets less and less accurate.

    Sorry no - newer HR monitors using variance in HR analysis are as closer to energy use for non-stready state cardio including lifestyle activity. See the FirstBeat research for this. They report a maximal error of 7-10%.

    I was unaware of this. Thanks for the info. Off to read!

    Here is the Firstbeat white paper section: https://www.firstbeat.com/science-and-physiology/white-papers-and-publications/

    Interesting. I will have to read up as well. I do wonder how many HRM manufactures and app developers for Bluetooth HRM straps are incorporating this at this point. There are a huge number out there, and it seems most people are using HRM models that have been around for a while. Anyway, thanks for the information. It looks like there is a lot to read. I will have to bookmark for later.

  • 20yearsyounger
    20yearsyounger Posts: 1,643 Member
    edited February 2016
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.

    I worry about my intake at that level of activity because I don't want to undereat.

    The OP said he didn't want to overeat. I can see it both ways. It just seems like if you can do that sort of athletic feat, I figure you must be Superman, and Superman should be able to eat freely without calcing out his burns and measuring his food. Clearly I'm no Superman, and not around many! ;)

    I also don't want to overeat but I want to eat enough to support training and to lose a bit of weight.
    I haven't done too many 4 hour rides, but I still counted when I did.

    I'm with the knowing what I need to eat back folks. I'm maintaining and I care about those numbers to fuel my activities. I could have been a much better athlete and reduce injury in my younger days if I had known more about this CICO thing. Instead, I just played, didn't fuel myself properly and often ran out of steam or got injured.

    OP, I wish I knew the answer but I noticed that as well with my Garmin runs and calculations. I haven't changed the weight but due to improved heart rate efficiency I have been getting lower numbers. Yesterday I did 7+ hours of exercise and I was a little disappointed with the number it gave me as well. However, I just go with the lower number. One less beer or cookie I guess.
  • rileysowner
    rileysowner Posts: 8,228 Member
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    HR monitors are only accurate as an estimate for steady state cardio. While a bike ride could be steady state, I know in my rides there is a fair amount of variation due to the fact that there are hills, valleys, wind, and even changes in road surface. All of that makes it less true steady state. Add to that the inevitable HR drift that comes from long periods of time spent at an exercise activity which will skew the results, and the HR calorie estimate gets less and less accurate.

    Sorry no - newer HR monitors using variance in HR analysis are as closer to energy use for non-stready state cardio including lifestyle activity. See the FirstBeat research for this. They report a maximal error of 7-10%.

    Also, wasn't the issue with non-steady state cardio that you would get overinflated estimates due to the HR going up and down?

    OP, I'd hardly call 1678 feeble.
    Personally, I err on the side of caution and go with the lower one. If you really want, split the difference.

    I was thinking this as well. That's about 450 calories per hour.

    Then again, the METS value for cycling that fast is 12, which would be way more than 450 calories per hour.

    Are you sure you went that far? That's 18mph for almost 4 hours. :o

    I have never done it in the winter, but I know once I get back into the groove in the late spring and summer I can average 20mph on 2-3 hour rides on my mountain bike, sometimes more. With the snow and ice we have in the winter, if I dared to ride, I am guessing it would be far below that. It doesn't seem unrealistic if one rides a lot.
  • TavistockToad
    TavistockToad Posts: 35,719 Member
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    I'm finding I am getting significantly lower burns at the moment with running in the cold weather (2°c in the uk this morning). I have the garmin 225 wrist monitor. It claimed my heart rate was 79 after 6 miles running this morning!
  • tincanonastring
    tincanonastring Posts: 3,944 Member
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.

    I worry about my intake at that level of activity because I don't want to undereat.

    The OP said he didn't want to overeat. I can see it both ways. It just seems like if you can do that sort of athletic feat, I figure you must be Superman, and Superman should be able to eat freely without calcing out his burns and measuring his food. Clearly I'm no Superman, and not around many! ;)

    I also don't want to overeat but I want to eat enough to support training and to lose a bit of weight.
    I haven't done too many 4 hour rides, but I still counted when I did.

    I was so mad when I blew through my calories after running a half. I finished the run and thought I could eat for days without blowing through that burn. Lolz.

    How many was that?

    I'd have to go back and look, but it was a decent amount. I'm fat and slow; average pace, IIRC, was 10:10, so the run duration would have been close to 2:10:00.
  • WalkingAlong
    WalkingAlong Posts: 4,926 Member
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    HR monitors are only accurate as an estimate for steady state cardio. While a bike ride could be steady state, I know in my rides there is a fair amount of variation due to the fact that there are hills, valleys, wind, and even changes in road surface. All of that makes it less true steady state. Add to that the inevitable HR drift that comes from long periods of time spent at an exercise activity which will skew the results, and the HR calorie estimate gets less and less accurate.

    Sorry no - newer HR monitors using variance in HR analysis are as closer to energy use for non-stready state cardio including lifestyle activity. See the FirstBeat research for this. They report a maximal error of 7-10%.

    Also, wasn't the issue with non-steady state cardio that you would get overinflated estimates due to the HR going up and down?

    OP, I'd hardly call 1678 feeble.
    Personally, I err on the side of caution and go with the lower one. If you really want, split the difference.

    I was thinking this as well. That's about 450 calories per hour.

    Then again, the METS value for cycling that fast is 12, which would be way more than 450 calories per hour.

    Are you sure you went that far? That's 18mph for almost 4 hours. :o

    I have never done it in the winter, but I know once I get back into the groove in the late spring and summer I can average 20mph on 2-3 hour rides on my mountain bike, sometimes more. With the snow and ice we have in the winter, if I dared to ride, I am guessing it would be far below that. It doesn't seem unrealistic if one rides a lot.

    Wow, 20mph on a mountain bike. I'm just slow. Though I think a friend's riding group does average 17mph, he said.

    The idea of 12 METS for hours straight is odd to me but I kind of doubt you guys who can do that speed for that distance are really at 12 METS. To me, that's 'puke in a bucket' exertion. I remember Cathe Friedrich saying about 10 METS was most peoples' max for a tough, hour long cardio session.
  • ConicalFern
    ConicalFern Posts: 121 Member
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    Wow, I'm surprised you need to worry about your intake at all with that sort of activity, assuming it's not a rare event!

    If you want a third estimate take your BMR per minute X 12 METS times minutes of the ride. It's going to be higher than both of those, I think. Even with my puny BMR it'd be over 2200 calories.

    I worry about my intake at that level of activity because I don't want to undereat.

    The OP said he didn't want to overeat. I can see it both ways. It just seems like if you can do that sort of athletic feat, I figure you must be Superman, and Superman should be able to eat freely without calcing out his burns and measuring his food. Clearly I'm no Superman, and not around many! ;)

    I also don't want to overeat but I want to eat enough to support training and to lose a bit of weight.
    I haven't done too many 4 hour rides, but I still counted when I did.

    I was so mad when I blew through my calories after running a half. I finished the run and thought I could eat for days without blowing through that burn. Lolz.

    How many was that?

    I'd have to go back and look, but it was a decent amount. I'm fat and slow; average pace, IIRC, was 10:10, so the run duration would have been close to 2:10:00.

    At my weight that's 2486 according to Runner's world :) . I guess on the upside, it's rare that you can eat that many calories and and not actually go over your allowance by too much - imagine eating that much of a non-exercise day!