Welcome to Debate Club! Please be aware that this is a space for respectful debate, and that your ideas will be challenged here. Please remember to critique the argument, not the author.

The Fat Burning Zone

bizgirl26
bizgirl26 Posts: 1,795 Member
edited November 16 in Debate Club
So I am just wondering how many people really pay attention to this rule? I tend to have a lower resting hear rate so for me I tend to stay close to the "Fat burning target heart rate zone' however I never try or paid any attention until it was mentioned and certainly I am losing lots of fat lok and I want to improve cardiovascular health so I try to do bursts of higher intensity anyway.
FYI... To Figure out your max heart rate (Max Heart Rate = 220 – your age). And then determine your fat-burning range, which is 60% to 70% of your max heart rate. It seems really low to me . As a 45 year old woman my fat burning range is 109-127 BPM. Some people people believe just go all out and you burns lots anyway. Thoughts? Hogwash or not ? I am going to keep doing what I have always done anyway ;)

Replies

  • fbchick51
    fbchick51 Posts: 240 Member
    BeauNash wrote: »
    The "fat-burning zone" is a misunderstandng of physiology that unfortunately is perpetuated by the fitness industry.

    Whilst the percentage of total calories that are sourced from fat may be highest in the so-called "fat-burning range", the amount of calories that are sourced from fat are greater at the higher heart rates that are associated with harder physical effort.

    As an example, 80% of 200 calories is less than 60% of 300 calories.

    This. I don't even worry too much about my HR during workouts. I tend to enjoy the HIIT style workouts, but it causes my HR to fluctuate all over the place... So it works better to just listen to my body. I set my HI intervals to be hard enough that my form gets a bit sloppy at the end of the interval and set my recovery intervals low enough that I can survive the next HI phase.
  • stealthq
    stealthq Posts: 4,298 Member
    Fat burning zone doesn't mean what you're thinking it means. Forget any idea about burning more fat for fuel, it doesn't really translate into burning more body fat.

    The fat burning zone is good for any exercise you intend to keep up for long periods of time and when you're trying to increase endurance. You can burn many more calories at this level of effort than any other simply because if you are fit enough, you can literally keep this level of effort up all day. Doesn't work that way for the typical 30-60 min cardio workout, though.

    The highest level of effort that you can put out for the duration of your workout is the one that will burn the most calories and therefore the most body fat (if you're in a deficit).

    Also, if you want to use heart rate zones as a training aid, don't figure your max heart rate that way. It's not accurate for a large portion of the population. If you want to know your max heart rate, do a lactate threshold test and that'll get you a workable estimate.
  • Legion229
    Legion229 Posts: 33 Member
    The argument is that low-intensity aerobic training will allow your body to use more fat as an energy source, thereby accelerating the loss of body fat. ... Although the fat burning zone burns a higher percentage of fat of the total calories expended, it does not burn more calories than training in high intensity.
  • yarwell
    yarwell Posts: 10,477 Member
    edited March 2017
    Your best bet is to get a metablic assessment where you exercise on a bike or treadmill at progressively higher heart rates and breath through a mask into a gas analyser that calculates what you're burning :- dntc3ed14aet.jpg

    (Male, 51). Here you can see through the broscience that I wasn't burning any significant fat above about 120 bpm
  • Azdak
    Azdak Posts: 8,281 Member
    Legion229 wrote: »
    The argument is that low-intensity aerobic training will allow your body to use more fat as an energy source, thereby accelerating the loss of body fat. ... Although the fat burning zone burns a higher percentage of fat of the total calories expended, it does not burn more calories than training in high intensity.

    And the fat you burn isn't stored body fat.
  • Azdak
    Azdak Posts: 8,281 Member
    yarwell wrote: »
    Your best bet is to get a metablic assessment where you exercise on a bike or treadmill at progressively higher heart rates and breath through a mask into a gas analyser that calculates what you're burning :- dntc3ed14aet.jpg

    (Male, 51). Here you can see through the broscience that I wasn't burning any significant fat above about 120 bpm

    Not exactly sure what point you are trying to make. Are you trying to say there is no "fat burning" zone because your fat oxidation dropped at such a low level of exertion?

  • NorthCascades
    NorthCascades Posts: 10,968 Member
    bizgirl26 wrote: »
    So I am just wondering how many people really pay attention to this rule?

    What rule are you asking about, exactly?
  • VintageFeline
    VintageFeline Posts: 6,771 Member
    bizgirl26 wrote: »
    So I am just wondering how many people really pay attention to this rule?

    What rule are you asking about, exactly?

    Yeah. Is this a question about losing more body fat by training at a particular heart rate (which is nonsense because a calorie deficit is what reduces body fat) or the energy source the body uses to fuel activity and the benefits of it being fat vs glycogen?
  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    bizgirl26 wrote: »
    So I am just wondering how many people really pay attention to this rule? I tend to have a lower resting hear rate so for me I tend to stay close to the "Fat burning target heart rate zone' however I never try or paid any attention until it was mentioned and certainly I am losing lots of fat lok and I want to improve cardiovascular health so I try to do bursts of higher intensity anyway.
    FYI... To Figure out your max heart rate (Max Heart Rate = 220 – your age). And then determine your fat-burning range, which is 60% to 70% of your max heart rate. It seems really low to me . As a 45 year old woman my fat burning range is 109-127 BPM. Some people people believe just go all out and you burns lots anyway. Thoughts? Hogwash or not ? I am going to keep doing what I have always done anyway ;)

    The fat burning zone simply means that for that particular activity, you're primarily using fat as fuel...we primarily burn fat when we're sitting around too...and you burn more fat for fuel sleeping than any other thing you do.

    Your body is constantly cycling between fuel sources and constantly cycling between fat storage and fat oxidation. Your actual net fat oxidation is going to be as per your energy deficiency, not working in a particular zone.

    More intense cardiovascular work is going to expend more energy overall.
  • yarwell
    yarwell Posts: 10,477 Member
    Azdak wrote: »
    Legion229 wrote: »
    The argument is that low-intensity aerobic training will allow your body to use more fat as an energy source, thereby accelerating the loss of body fat. ... Although the fat burning zone burns a higher percentage of fat of the total calories expended, it does not burn more calories than training in high intensity.

    And the fat you burn isn't stored body fat.

    what is it - inhaled fat ?
  • Ironandwine69
    Ironandwine69 Posts: 2,432 Member
    I never have paid attention to it. I'm too busy watching my form, having fun and kicking *kitten*( okay not always kicking *kitten* here, but ya know what I mean)
  • rileysowner
    rileysowner Posts: 8,337 Member
    Azdak wrote: »
    yarwell wrote: »
    Azdak wrote: »
    Legion229 wrote: »
    The argument is that low-intensity aerobic training will allow your body to use more fat as an energy source, thereby accelerating the loss of body fat. ... Although the fat burning zone burns a higher percentage of fat of the total calories expended, it does not burn more calories than training in high intensity.

    And the fat you burn isn't stored body fat.

    what is it - inhaled fat ?

    It is not stored (subcutaneous or visceral) adipose tissue. The majority of fat used during exercise comes from triglycerides already stored in the muscle cells. While stored body fat (as described above) is mobilized during exercise, not much of it is used--it's set out in case it's needed and then put back when you are finished.

    Stored body fat (as described above) is affected by long-term energy balance, not by fuel substrate mix during exercise (except possibly in the very lean).

    Your logic is fascinating.

    You are ignoring his point. The fat used to power activity is not body fat (adipose tissues) but triglycerides. Just because he used the word stored, doesn't change the fact that most people who misunderstand the fat burning zone thing the fat being burned is the body fat. It isn't. It is the triglycerides in your muscles and blood. What affects overall body fat is an energy deficit, not whether you burn mainly fat (triglycerides) or carbs (glycogen) during your exercise times.
  • Gianfranco_R
    Gianfranco_R Posts: 1,297 Member
    Azdak wrote: »
    yarwell wrote: »
    Azdak wrote: »
    Legion229 wrote: »
    The argument is that low-intensity aerobic training will allow your body to use more fat as an energy source, thereby accelerating the loss of body fat. ... Although the fat burning zone burns a higher percentage of fat of the total calories expended, it does not burn more calories than training in high intensity.

    And the fat you burn isn't stored body fat.

    what is it - inhaled fat ?

    It is not stored (subcutaneous or visceral) adipose tissue. The majority of fat used during exercise comes from triglycerides already stored in the muscle cells. While stored body fat (as described above) is mobilized during exercise, not much of it is used--it's set out in case it's needed and then put back when you are finished.

    Stored body fat (as described above) is affected by long-term energy balance, not by fuel substrate mix during exercise (except possibly in the very lean).

    Your logic is fascinating.

    You are ignoring his point. The fat used to power activity is not body fat (adipose tissues) but triglycerides. Just because he used the word stored, doesn't change the fact that most people who misunderstand the fat burning zone thing the fat being burned is the body fat. It isn't. It is the triglycerides in your muscles and blood. What affects overall body fat is an energy deficit, not whether you burn mainly fat (triglycerides) or carbs (glycogen) during your exercise times.

    Oh, I see, so we burn triglycerides, and store as adipose tissue ... What ? Fatty acids? :smile:
    You learn so many things here on mfp...
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    What point do you think you are making, Gianfranco?

    What significance is it whether one is in the "fat burning zone" vs. a more intense level of exercise for fat loss? (Obviously it has some relevance for some kinds of training purposes, as North Cascades indicated.)
  • rileysowner
    rileysowner Posts: 8,337 Member
    Azdak wrote: »
    yarwell wrote: »
    Azdak wrote: »
    Legion229 wrote: »
    The argument is that low-intensity aerobic training will allow your body to use more fat as an energy source, thereby accelerating the loss of body fat. ... Although the fat burning zone burns a higher percentage of fat of the total calories expended, it does not burn more calories than training in high intensity.

    And the fat you burn isn't stored body fat.

    what is it - inhaled fat ?

    It is not stored (subcutaneous or visceral) adipose tissue. The majority of fat used during exercise comes from triglycerides already stored in the muscle cells. While stored body fat (as described above) is mobilized during exercise, not much of it is used--it's set out in case it's needed and then put back when you are finished.

    Stored body fat (as described above) is affected by long-term energy balance, not by fuel substrate mix during exercise (except possibly in the very lean).

    Your logic is fascinating.

    You are ignoring his point. The fat used to power activity is not body fat (adipose tissues) but triglycerides. Just because he used the word stored, doesn't change the fact that most people who misunderstand the fat burning zone thing the fat being burned is the body fat. It isn't. It is the triglycerides in your muscles and blood. What affects overall body fat is an energy deficit, not whether you burn mainly fat (triglycerides) or carbs (glycogen) during your exercise times.

    Oh, I see, so we burn triglycerides, and store as adipose tissue ... What ? Fatty acids? :smile:
    You learn so many things here on mfp...

    So what is your point? Outside of some fairly specific instances are heart rate training zones important. In terms of fat loss, they are not for the various reasons posted.
  • AnnPT77
    AnnPT77 Posts: 34,627 Member
    And 220-age is a pretty poor estimator of max heart rate. I'm 61, so 220 - age is 159. Actual max (tested) is around 181. It's been a while since I tested, but I still see HR way above 159 during workouts (and I'm not that taxed when it happens).

    For training (not fat loss) purposes, if I assumed HR max was 159, I'd seriously under-train. 159 is just slitghtly into my anaerobic threshold zone.

    And I'm not a special snowflake - this degree of deviation from 220-age is pretty common.

    HR zones are useful for training, IMO, but a big "who cares" for weight loss, for reasons cited above. And for training purposes, I think you most usefully wanna be calculating them off actual max and actual resting, not age estimates.

  • Azdak
    Azdak Posts: 8,281 Member
    AnnPT77 wrote: »
    And 220-age is a pretty poor estimator of max heart rate. I'm 61, so 220 - age is 159. Actual max (tested) is around 181. It's been a while since I tested, but I still see HR way above 159 during workouts (and I'm not that taxed when it happens).

    For training (not fat loss) purposes, if I assumed HR max was 159, I'd seriously under-train. 159 is just slitghtly into my anaerobic threshold zone.

    And I'm not a special snowflake - this degree of deviation from 220-age is pretty common.

    HR zones are useful for training, IMO, but a big "who cares" for weight loss, for reasons cited above. And for training purposes, I think you most usefully wanna be calculating them off actual max and actual resting, not age estimates.

    I've been fighting this battle online for over 20 years. Both the "fat burning zone" idea and the growth of the internet and the availability of heart rate monitors occurred at about the same time 1994-5). I can't tell you how many hundreds of people (thousands?) I've had to say this to. People who were slowing down to a crawl because their HR response to exercise did not follow the 220-age pattern.

    Hypothetically, about 16% of the population will have a true HR max 20-35 beats higher than the age-predicted number. In reality, it seems like twice that.

    The other problem no one even gets to is the fact that if you just take a percentage of HR max and don't include resting HR, you throw in another error factor of 15%-20%.

    If one knows or has a sense of true HR max and uses the the HR reserve (Karvonen) formula to calculate target HRs, then you can come up with some meaningful and useful "zones". But for most people, RPE works just as well.
  • girlgroves
    girlgroves Posts: 235 Member
    Azdak wrote: »
    AnnPT77 wrote: »
    And 220-age is a pretty poor estimator of max heart rate. I'm 61, so 220 - age is 159. Actual max (tested) is around 181. It's been a while since I tested, but I still see HR way above 159 during workouts (and I'm not that taxed when it happens).

    For training (not fat loss) purposes, if I assumed HR max was 159, I'd seriously under-train. 159 is just slitghtly into my anaerobic threshold zone.

    And I'm not a special snowflake - this degree of deviation from 220-age is pretty common.

    HR zones are useful for training, IMO, but a big "who cares" for weight loss, for reasons cited above. And for training purposes, I think you most usefully wanna be calculating them off actual max and actual resting, not age estimates.

    I've been fighting this battle online for over 20 years. Both the "fat burning zone" idea and the growth of the internet and the availability of heart rate monitors occurred at about the same time 1994-5). I can't tell you how many hundreds of people (thousands?) I've had to say this to. People who were slowing down to a crawl because their HR response to exercise did not follow the 220-age pattern.

    Hypothetically, about 16% of the population will have a true HR max 20-35 beats higher than the age-predicted number. In reality, it seems like twice that.

    The other problem no one even gets to is the fact that if you just take a percentage of HR max and don't include resting HR, you throw in another error factor of 15%-20%.

    If one knows or has a sense of true HR max and uses the the HR reserve (Karvonen) formula to calculate target HRs, then you can come up with some meaningful and useful "zones". But for most people, RPE works just as well.

    This is all really interesting - I've just had to google RPE!
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    AnnPT77 wrote: »
    And 220-age is a pretty poor estimator of max heart rate. I'm 61, so 220 - age is 159. Actual max (tested) is around 181. It's been a while since I tested, but I still see HR way above 159 during workouts (and I'm not that taxed when it happens).

    For training (not fat loss) purposes, if I assumed HR max was 159, I'd seriously under-train. 159 is just slitghtly into my anaerobic threshold zone.

    And I'm not a special snowflake - this degree of deviation from 220-age is pretty common.

    HR zones are useful for training, IMO, but a big "who cares" for weight loss, for reasons cited above. And for training purposes, I think you most usefully wanna be calculating them off actual max and actual resting, not age estimates.

    Yep, this is me too, and why I prefer -- for training purposes, not weight loss, of course -- to focus on perceived exertion.
  • gailsy619
    gailsy619 Posts: 5 Member
    bizgirl26 wrote: »
    So I am just wondering how many people really pay attention to this rule? I tend to have a lower resting hear rate so for me I tend to stay close to the "Fat burning target heart rate zone' however I never try or paid any attention until it was mentioned and certainly I am losing lots of fat lok and I want to improve cardiovascular health so I try to do bursts of higher intensity anyway.
    FYI... To Figure out your max heart rate (Max Heart Rate = 220 – your age). And then determine your fat-burning range, which is 60% to 70% of your max heart rate. It seems really low to me . As a 45 year old woman my fat burning range is 109-127 BPM. Some people people believe just go all out and you burns lots anyway. Thoughts? Hogwash or not ? I am going to keep doing what I have always done anyway ;)

    My fat burning number is 84...I'm 56...
  • NorthCascades
    NorthCascades Posts: 10,968 Member
    The zone breakpoints have to do with your body's metabolism of energy substrates, mostly fat and carbs and thus production of lactate.

    Here's a good article about a simplified zone system based on your breathing instead of your heart rate.

    https://www.acefitness.org/blog/1165/understanding-vt1-and-vt2

    Research has found that the Talk Test (as described on pgs 382-383 in the Personal Trainer Manual) provides an accurate measure of the body’s response to increasing intensity. Where before we relied solely on percentage of heart rate, now we have discovered that talk test relates very well to similar intensities.

    Below VT1: you can speak comfortably, recite the alphabet etc.

    At VT1: you can no longer speak comfortably; it requires some effort at this point

    Above VT1/Below VT2: speaking is possible, but not really comfortable, you can’t recite the entire alphabet with ease at this point

    At VT2: Speaking is no longer possible with the exception of one or two word statements, chances are you are not going to be able to exercise much longer above this point


    Again, weight (fat) loss comes from a calorie deficit. This is about pacing yourself during long events.
  • AnnPT77
    AnnPT77 Posts: 34,627 Member
    The zone breakpoints have to do with your body's metabolism of energy substrates, mostly fat and carbs and thus production of lactate.

    Here's a good article about a simplified zone system based on your breathing instead of your heart rate.

    https://www.acefitness.org/blog/1165/understanding-vt1-and-vt2

    Research has found that the Talk Test (as described on pgs 382-383 in the Personal Trainer Manual) provides an accurate measure of the body’s response to increasing intensity. Where before we relied solely on percentage of heart rate, now we have discovered that talk test relates very well to similar intensities.

    Below VT1: you can speak comfortably, recite the alphabet etc.

    At VT1: you can no longer speak comfortably; it requires some effort at this point

    Above VT1/Below VT2: speaking is possible, but not really comfortable, you can’t recite the entire alphabet with ease at this point

    At VT2: Speaking is no longer possible with the exception of one or two word statements, chances are you are not going to be able to exercise much longer above this point


    Again, weight (fat) loss comes from a calorie deficit. This is about pacing yourself during long events.

    Good link.

    More generally, as it indicates, heart rate zones are also about training yourself for many types of competitive events, some of which may focus more on cardiovascular/O2 implications than on fuel per se. My sport, rowing, is a short, power-endurance activity, in the commonest form of competition (2K sprint). At elite levels, it's an anaerobic start, high-aerobic middle (longest segment), anaerobic sprint to finish . . . and even us chintzy amateurs train in that direction. This is of course not the only sport with its own particular demands and specifically tailored training (in this sense, all sports are unique ;) ).

    So the HR zones are also about the training, needed if one works a periodized cardiovascular training plan to improve anaerobic threshold (among other things), not just about the fueling during races (though I understand the point about fuel source being relevant to the zone definitions, and of extreme importance to long endurance events).

    It's still true that for general health & fitness purposes, worrying about this is over-thinking. Even for training, the RPE methods (including the talk-test method you mention) can be used, and are a better guide if you don't know actual HR max, VO2 max, etc.
This discussion has been closed.