does walking for 2 hours really burn 400-500ish cals???!!

2

Replies

  • scarlett_k
    scarlett_k Posts: 796 Member
    edited November 2020
    .
  • brianpperkins131
    brianpperkins131 Posts: 90 Member
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.
  • scarlett_k
    scarlett_k Posts: 796 Member
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.

    30 calories per mile for every pound of body weight? That makes no sense, you're saying a 2 mile walk would for a 150lb person burn 30*2*150 calories? 🙃 not sure your maths is to be trusted.
  • Dogmom1978
    Dogmom1978 Posts: 1,581 Member
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.

    ???
    Maybe you mean 30 calories per mile for every 100 lbs??? Not sure where you got that from either though, but certainly a more reasonable guesstimate.
  • yirara
    yirara Posts: 7,359 Member
    scarlett_k wrote: »
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.

    30 calories per mile for every pound of body weight? That makes no sense, you're saying a 2 mile walk would for a 150lb person burn 30*2*150 calories? 🙃 not sure your maths is to be trusted.

    Just a minor decimal mistake. Basically it's 0.3 calories per mile per lbs of body weight. Or roughly 0.41 per km per kg bodyweight. Yes, it's not a lot. But walking on two feet is our primary mode of motion. Of course calorie burn for that is fairly low, as is walking on four feed for most other mammals.
  • nanastaci2020
    nanastaci2020 Posts: 1,044 Member
    edited November 2020
    My values are from Fitbit + data on losing as expected based on CICO. The equation referenced is flat ground, not incline. That equation indicates I burn about 2.6 cals per minute walking (flat) 4 mph. My actual net is about twice that, again supported by weight loss data. (Though again, my actual does include some incline but not enough to make up for the vast difference.)

    But in general, for someone who has no method to evaluate a burn rate, it would be wise to assume a low # until they have data to indicate otherwise.
    yirara wrote: »
    I walk briskly on a treadmill at a slight incline around 4 mph, burn almost 400 in the hour. If I were sitting on the couch, I would burn 55 roughly in an hour. So my gain is about 325 to 345. If I walked slower I'd burn a little less.

    I am female, 46, 130ish.

    This seems unlikely to be honest. See the equation that Sijomial posted above. Don't trust numbers on machines.

  • dragon_girl26
    dragon_girl26 Posts: 2,182 Member
    edited November 2020
    Dogmom1978 wrote: »
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.

    ???
    Maybe you mean 30 calories per mile for every 100 lbs??? Not sure where you got that from either though, but certainly a more reasonable guesstimate.

    Thats what I'm thinking. My main form...pretty much my only form..of exercise is walking these days. I walk about 6 miles a day, and I know I'm burning more than 180 calories because I lose 1 lb a week on 1800 - 2000 calories, when my base number for sedentary is 1350. (179lb, 5'5" for reference). Outside of that walking, I'm pretty much a slug. Lol
  • brianpperkins131
    brianpperkins131 Posts: 90 Member
    edited November 2020
    scarlett_k wrote: »
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.

    30 calories per mile for every pound of body weight? That makes no sense, you're saying a 2 mile walk would for a 150lb person burn 30*2*150 calories? 🙃 not sure your maths is to be trusted.
    Dogmom1978 wrote: »
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.

    ???
    Maybe you mean 30 calories per mile for every 100 lbs??? Not sure where you got that from either though, but certainly a more reasonable guesstimate.
    Dogmom1978 wrote: »
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.

    ???
    Maybe you mean 30 calories per mile for every 100 lbs??? Not sure where you got that from either though, but certainly a more reasonable guesstimate.

    Thats what I'm thinking. My main form...pretty much my only form..of exercise is walking these days. I walk about 6 miles a day, and I know I'm burning more than 180 calories because I lose 1 lb a week on 1800 - 2000 calories, when my base number for sedentary is 1350. (179lb, 5'5" for reference). Outside of that walking, I'm pretty much a slug. Lol
    Typo. Per 100.

    Weight in pounds X .3 X distance in miles. 100 lbs x .3 x 1 mile = 30 ... Syracuse University study published several years ago in Runner's World. (179 X .3 X 6 = 322, not 180)

    Burning 200 net calories per half hour from walking requires either moving a lot of weight at a brisk pace, moving at a faster than walking pace, or going up a steep incline.
  • Dogmom1978
    Dogmom1978 Posts: 1,581 Member
    scarlett_k wrote: »
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.

    30 calories per mile for every pound of body weight? That makes no sense, you're saying a 2 mile walk would for a 150lb person burn 30*2*150 calories? 🙃 not sure your maths is to be trusted.
    Dogmom1978 wrote: »
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.

    ???
    Maybe you mean 30 calories per mile for every 100 lbs??? Not sure where you got that from either though, but certainly a more reasonable guesstimate.
    Dogmom1978 wrote: »
    scarlett_k wrote: »
    Doesn't sound unreasonable. I burn about 200 per half hour or so of walking at a good pace.

    The math comes out to about 30 calories per mile for every pound of body weight on relatively flat ground. At a brisk, 4mph pace you'd cover 2 miles in a half hour ... 90 cals for a 150 lb person ... 120 cals for a 200 lb person ... 180 cals for a 300 lb person.

    ???
    Maybe you mean 30 calories per mile for every 100 lbs??? Not sure where you got that from either though, but certainly a more reasonable guesstimate.

    Thats what I'm thinking. My main form...pretty much my only form..of exercise is walking these days. I walk about 6 miles a day, and I know I'm burning more than 180 calories because I lose 1 lb a week on 1800 - 2000 calories, when my base number for sedentary is 1350. (179lb, 5'5" for reference). Outside of that walking, I'm pretty much a slug. Lol
    Typo. Per 100.

    Weight in pounds X .3 X distance in miles. 100 lbs x .3 x 1 mile = 30 ... Syracuse University study published several years ago in Runner's World. (179 X .3 X 6 = 322, not 180)

    Burning 200 net calories per half hour from walking requires either moving a lot of weight at a brisk pace, moving at a faster than walking pace, or going up a steep incline.


    Yes, my outdoor walking burns very little. Hiking a lot more due to challenging terrain and elevation changes.

    Indoors on my treadmill, I set it to 3.4 mph with an incline of 10. Sometimes I do hill mode instead, but if I’m short on time and just want some extra calories for a snack, the higher overall incline is the way to go.
  • AnnPT77
    AnnPT77 Posts: 24,860 Member
    As sijomial says, weight loss results as expected don't confirm the accuracy of a specific exercise calorie estimating formula. Weight loss results that are as expected confirm that a person has dialed in a workable calorie level given the accuracy of their food logging, and the totality of their activity level; and they've gained strategies they personally can use moving forward.

    To use an intentionally and clearly absurd example: I barely walk at all (very sedentary outside of non-walking exercise), but will predictably lose about a pound a month on 1850 net calories. Since MFP predicts I'd maintain at around 1500, the implication could be that not-walking burns at least 475 calories per day (350 discrepancy from "maintenance" calories, plus 125 calorie deficit). Pretty sure it doesn't. 😆 Doesn't matter, my weight behaves as expected. That doesn't generalize to others who are 5'5", 125 pounds, sedentary, age 65. Waaaay doesn't.

    This is not to minimize the accomplishment of people who've figured out a personal equation (approximation) that works: That's absolutely the goal for all of us. It's perfect, in fact. But it doesn't necessarily generalize to other people.

    Where available, using research-derived formulas or other estimating methods is a more generalizable idea, and even that isn't perfect. It's useful to understand the ways in which an individual person may not have the same results as the averages derived from the research, too.
  • frankwbrown
    frankwbrown Posts: 7,535 Member
    ninerbuff wrote: »
    ...
    Zone 3 is a good zone for getting cardio benefit as well as fat burning.
    ...
    While the percentage of fat burned is higher at lower intensities, you STILL burn more fat if the intensity was higher over the same period of time. I hate the "fat burning" zone analogy from the fitness industry. It's misleading to many. Go to just about any gym in the USA and you'll find 10 people doing the same "fat burning" cardio routine day in day out. And they NEVER CHANGE in physical appearance especially if they are overweight. It still comes down to CICO.
    Also the fat being burned (unless they've been fasting for like 12 hours and on a calorie deficit) ISN'T stored body fat.
    ...

    I agree with you:
    1. Of course, you continue to burn fat (energy, at least) at higher levels of exertion (although see below).
    2. Burning body fat will only happen if you are dieting appropriately. This is true whether you are doing aerobic metabolism or anaerobic metabolism. Burning fat only happens when the body needs to produce glycogen.
    3. As you say, CICO: if you don't burn more calories than you consume (actively and thru BMR), then you will not lose weight.

    My point, which I failed to make, is that staying in aerobic metabolism during exercise will not only burn fat but is highly beneficial for your cardiovascular system (heart, lungs, capillaries, etc.).

    Also, it is my understanding that body fat is converted only during aerobic metabolism. Anaerobic metabolism utilizes glycogen, not fat, and any conversion of body fat will take place after exercise, during EPOC and via aerobic metabolism. Of course, the net result is that body fat will be converted after exercise, to replace the glycogen that anaerobic exercise has depleted. This all presumes that the person doesn't ingesting too much glucose before, during or after exercise, eliminating the need to convert body fat in the first place.

    So, while there is benefit to anaerobic exercise (especially HIIT), the aerobic HR zone is vital for cardio conditioning, and aerobic metabolism is vital for burning body fat. I would recommend beginners to start with cardio and slowly begin incorporating HIIT.

  • lgfrie
    lgfrie Posts: 1,447 Member
    It's better to go by mileage than time, when trying to estimate walking calories. However, the numbers do kinda add up - 6 miles in 2 hours, that's 3 mph and sounds about right for what you're doing.

    Roughly speaking, ballpark for your weight, you should be burning around 320 net calories. You're also burning another 150 or so BMR calories (the ones you get just for existing), but 470 would be double counting those last 150. 320 is probably quite close to the "real" number of additional calories you are burning via this exercise, and could eat back and so forth.
  • kshama2001
    kshama2001 Posts: 25,627 Member
    trulyhealy wrote: »
    i don’t have a watch to track it but i just googled how many calories does someone my weight would roughly burn for walking for 2 hours and it seems like overestimate. what do you think? i don’t want to overestimate and then eat a portion of the calories back

    also should i consider it exercise?? bc i just walk to work now and i go to the gym too. just doesn’t seem as much effort as the gym sorry if this makes no sense
    trulyhealy wrote: »
    about 3 miles one way so 6 miles a day 3 times a week and i’m 142lbs and i wouldn’t say u speed walk kind of casual depending if i’m in a rush but i might start walking quicker to burn more

    So you are doing 3 miles per hour?

    When you use the "Walking, 3.0 mph, mod. pace" entry from MFP, how many calories do you get for the two hours?
  • Dogmom1978
    Dogmom1978 Posts: 1,581 Member
    ninerbuff wrote: »
    ...
    Zone 3 is a good zone for getting cardio benefit as well as fat burning.
    ...
    While the percentage of fat burned is higher at lower intensities, you STILL burn more fat if the intensity was higher over the same period of time. I hate the "fat burning" zone analogy from the fitness industry. It's misleading to many. Go to just about any gym in the USA and you'll find 10 people doing the same "fat burning" cardio routine day in day out. And they NEVER CHANGE in physical appearance especially if they are overweight. It still comes down to CICO.
    Also the fat being burned (unless they've been fasting for like 12 hours and on a calorie deficit) ISN'T stored body fat.
    ...

    I agree with you:
    1. Of course, you continue to burn fat (energy, at least) at higher levels of exertion (although see below).
    2. Burning body fat will only happen if you are dieting appropriately. This is true whether you are doing aerobic metabolism or anaerobic metabolism. Burning fat only happens when the body needs to produce glycogen.
    3. As you say, CICO: if you don't burn more calories than you consume (actively and thru BMR), then you will not lose weight.

    My point, which I failed to make, is that staying in aerobic metabolism during exercise will not only burn fat but is highly beneficial for your cardiovascular system (heart, lungs, capillaries, etc.).

    Also, it is my understanding that body fat is converted only during aerobic metabolism. Anaerobic metabolism utilizes glycogen, not fat, and any conversion of body fat will take place after exercise, during EPOC and via aerobic metabolism. Of course, the net result is that body fat will be converted after exercise, to replace the glycogen that anaerobic exercise has depleted. This all presumes that the person doesn't ingesting too much glucose before, during or after exercise, eliminating the need to convert body fat in the first place.

    So, while there is benefit to anaerobic exercise (especially HIIT), the aerobic HR zone is vital for cardio conditioning, and aerobic metabolism is vital for burning body fat. I would recommend beginners to start with cardio and slowly begin incorporating HIIT.

    Ummm....

    There is 0 need for anyone to do HIIT...

    CICO is all that matters for weight loss and yes, that includes fat. Plenty of people have hit goal weight while doing 0 cardio OR HIIT workouts. How can this be??? Well, your body needs energy. If you eat fewer calories than your body needs for that energy, it will get energy from fat reserves (and yes, also some muscle which is why weight training while in a deficit is useful to preserve muscle).

    That said, yes, aerobic exercise is useful to burn more fat, it just isn’t absolutely 100 % necessary as the post above makes it seem.

    Plus, exercise should be for HEALTH and not for weight loss. While some people find it helpful to exercise to remain in a deficit, to imply anywhere that it’s NECESSARY to lose fat is simply incorrect.
  • AnnPT77
    AnnPT77 Posts: 24,860 Member
    All of this is waaaay more geek-itude than OP needs, but . . .
    ninerbuff wrote: »
    ...
    Zone 3 is a good zone for getting cardio benefit as well as fat burning.
    ...
    While the percentage of fat burned is higher at lower intensities, you STILL burn more fat if the intensity was higher over the same period of time. I hate the "fat burning" zone analogy from the fitness industry. It's misleading to many. Go to just about any gym in the USA and you'll find 10 people doing the same "fat burning" cardio routine day in day out. And they NEVER CHANGE in physical appearance especially if they are overweight. It still comes down to CICO.
    Also the fat being burned (unless they've been fasting for like 12 hours and on a calorie deficit) ISN'T stored body fat.
    ...

    I agree with you:
    1. Of course, you continue to burn fat (energy, at least) at higher levels of exertion (although see below).
    2. Burning body fat will only happen if you are dieting appropriately. This is true whether you are doing aerobic metabolism or anaerobic metabolism. Burning fat only happens when the body needs to produce glycogen.
    Fat burn - even body fat burn - can potentially happen in the moment even if overall calorie intake doesn't result in net fat loss over time. Fueling is pretty dynamic, and the body's pretty good at balancing energy stores. It does that dynamically all day long, juggling recent-food sources and stored sources along the way.
    3. As you say, CICO: if you don't burn more calories than you consume (actively and thru BMR), then you will not lose weight.

    My point, which I failed to make, is that staying in aerobic metabolism during exercise will not only burn fat but is highly beneficial for your cardiovascular system (heart, lungs, capillaries, etc.).
    As is exercise at higher intensities, but the specific CV benefits (and other benefits) are somewhat different. Improved VO2 max is a CV benefit, for example. Higher intensity is the better tool for improving that dimension.
    Also, it is my understanding that body fat is converted only during aerobic metabolism. Anaerobic metabolism utilizes glycogen, not fat, and any conversion of body fat will take place after exercise, during EPOC and via aerobic metabolism. Of course, the net result is that body fat will be converted after exercise, to replace the glycogen that anaerobic exercise has depleted. This all presumes that the person doesn't ingesting too much glucose before, during or after exercise, eliminating the need to convert body fat in the first place.

    IMU, aerobic metabolism (an energy production process, loosely) and aerobic exercise (an intensity of human activity, loosely) are related, but not identical.

    In practice, use of energy sources (i.e., which energy production process is prioritized) during exercise is not an on-off switch. It's a variable contribution from carbohydrates or fats, with preferred source shifting gradually as intensity changes, and possibly even over the duration of steady-state exercise. That matters to fueling strategies more than it matters for weight management (or basic fitness improvement), though.

    It's not clear to me that which energy production system is most in play is *directly* related to CV benefits, however. Perhaps niner knows. Certainly O2 uptake rates are relevant to both, and some of the CV benefit could be thought of simply as making the heart muscle stronger by exercising it. (Presumably similar for lungs, blood vessels - dunno.)
    So, while there is benefit to anaerobic exercise (especially HIIT), the aerobic HR zone is vital for cardio conditioning, and aerobic metabolism is vital for burning body fat. I would recommend beginners to start with cardio and slowly begin incorporating HIIT.

    Agree that beginners should start with low/moderate steady state, for a variety of reasons. RPE (rate of perceived exertion**) is fine as a guide, especially for beginners. HR may mislead, especially if quite unfit. HR is more useful in a technical way IMO (i.e., performance tuning), though it's kind of fun. (And at that technical level, multiple HR zones are vital for conditioning.) But using HR for performance really does make it important to have a better estimate of HRmax than 220-age.

    But none of the technical detail really matters for OP's question, outside of possibly academic interest.

    **https://www.uofmhealth.org/health-library/ty6410abc, for example. There are lots of sources, some with better explanations of the levels, some with better explanations of the rationale or how to use.
  • frankwbrown
    frankwbrown Posts: 7,535 Member
    Dogmom1978 wrote: »
    ninerbuff wrote: »
    ...
    Zone 3 is a good zone for getting cardio benefit as well as fat burning.
    ...
    While the percentage of fat burned is higher at lower intensities, you STILL burn more fat if the intensity was higher over the same period of time. I hate the "fat burning" zone analogy from the fitness industry. It's misleading to many. Go to just about any gym in the USA and you'll find 10 people doing the same "fat burning" cardio routine day in day out. And they NEVER CHANGE in physical appearance especially if they are overweight. It still comes down to CICO.
    Also the fat being burned (unless they've been fasting for like 12 hours and on a calorie deficit) ISN'T stored body fat.
    ...

    I agree with you:
    1. Of course, you continue to burn fat (energy, at least) at higher levels of exertion (although see below).
    2. Burning body fat will only happen if you are dieting appropriately. This is true whether you are doing aerobic metabolism or anaerobic metabolism. Burning fat only happens when the body needs to produce glycogen.
    3. As you say, CICO: if you don't burn more calories than you consume (actively and thru BMR), then you will not lose weight.

    My point, which I failed to make, is that staying in aerobic metabolism during exercise will not only burn fat but is highly beneficial for your cardiovascular system (heart, lungs, capillaries, etc.).

    Also, it is my understanding that body fat is converted only during aerobic metabolism. Anaerobic metabolism utilizes glycogen, not fat, and any conversion of body fat will take place after exercise, during EPOC and via aerobic metabolism. Of course, the net result is that body fat will be converted after exercise, to replace the glycogen that anaerobic exercise has depleted. This all presumes that the person doesn't ingesting too much glucose before, during or after exercise, eliminating the need to convert body fat in the first place.

    So, while there is benefit to anaerobic exercise (especially HIIT), the aerobic HR zone is vital for cardio conditioning, and aerobic metabolism is vital for burning body fat. I would recommend beginners to start with cardio and slowly begin incorporating HIIT.

    Ummm....

    There is 0 need for anyone to do HIIT...

    CICO is all that matters for weight loss and yes, that includes fat. Plenty of people have hit goal weight while doing 0 cardio OR HIIT workouts. How can this be??? Well, your body needs energy. If you eat fewer calories than your body needs for that energy, it will get energy from fat reserves (and yes, also some muscle which is why weight training while in a deficit is useful to preserve muscle).

    That said, yes, aerobic exercise is useful to burn more fat, it just isn’t absolutely 100 % necessary as the post above makes it seem.

    Plus, exercise should be for HEALTH and not for weight loss. While some people find it helpful to exercise to remain in a deficit, to imply anywhere that it’s NECESSARY to lose fat is simply incorrect.

    I agree that exercise (of any kind) is not necessary in order to lose weight, as long as you are burning more calories than you are consuming. If I gave anyone that impression, I apologize. So to clarify, body fat is converted via aerobic metabolism (not aerobic "exercise"), and that can happen while you are sitting on the couch, provided there's not already plenty of glycogen in your blood.

    But HEALTH should be our primary concern, and that involves more than one's weight. In order to have healthy heart and lungs, you need to maintain a certain level of activity. That needn't be doing exercises per se. Some activities that people don't necessarily think of as exercise: gardening, taking walks or hikes for pleasure, etc.

    But in my specific case, I want to improve my cardio system and improve my muscle tone and flexibility. As a senior citizen, I am painfully aware of how one can lose flexibility and strength without realizing it. So for me, I intend to alter my lifestyle to include cardio exercise, strength training, and yoga. And eventually, I hope to return to doing tai chi which I did briefly four years ago or so. Yoga and tai chi are both good in that they are not just physical but mental as well. Peace of mind and a healthy body are my goals. Weight is just an indirect indicator of progress in the right direction.
  • frankwbrown
    frankwbrown Posts: 7,535 Member
    AnnPT77 wrote: »
    All of this is waaaay more geek-itude than OP needs, but . . .
    ...
    My point, which I failed to make, is that staying in aerobic metabolism during exercise will not only burn fat but is highly beneficial for your cardiovascular system (heart, lungs, capillaries, etc.).
    As is exercise at higher intensities, but the specific CV benefits (and other benefits) are somewhat different. Improved VO2 max is a CV benefit, for example. Higher intensity is the better tool for improving that dimension.
    Also, it is my understanding that body fat is converted only during aerobic metabolism. Anaerobic metabolism utilizes glycogen, not fat, and any conversion of body fat will take place after exercise, during EPOC and via aerobic metabolism. Of course, the net result is that body fat will be converted after exercise, to replace the glycogen that anaerobic exercise has depleted. This all presumes that the person doesn't ingesting too much glucose before, during or after exercise, eliminating the need to convert body fat in the first place.

    IMU, aerobic metabolism (an energy production process, loosely) and aerobic exercise (an intensity of human activity, loosely) are related, but not identical.

    In practice, use of energy sources (i.e., which energy production process is prioritized) during exercise is not an on-off switch. It's a variable contribution from carbohydrates or fats, with preferred source shifting gradually as intensity changes, and possibly even over the duration of steady-state exercise. That matters to fueling strategies more than it matters for weight management (or basic fitness improvement), though.

    It's not clear to me that which energy production system is most in play is *directly* related to CV benefits, however. Perhaps niner knows. Certainly O2 uptake rates are relevant to both, and some of the CV benefit could be thought of simply as making the heart muscle stronger by exercising it. (Presumably similar for lungs, blood vessels - dunno.)
    So, while there is benefit to anaerobic exercise (especially HIIT), the aerobic HR zone is vital for cardio conditioning, and aerobic metabolism is vital for burning body fat. I would recommend beginners to start with cardio and slowly begin incorporating HIIT.

    Agree that beginners should start with low/moderate steady state, for a variety of reasons. RPE (rate of perceived exertion**) is fine as a guide, especially for beginners. HR may mislead, especially if quite unfit. HR is more useful in a technical way IMO (i.e., performance tuning), though it's kind of fun. (And at that technical level, multiple HR zones are vital for conditioning.) But using HR for performance really does make it important to have a better estimate of HRmax than 220-age.

    But none of the technical detail really matters for OP's question, outside of possibly academic interest.

    **https://www.uofmhealth.org/health-library/ty6410abc, for example. There are lots of sources, some with better explanations of the levels, some with better explanations of the rationale or how to use.

    I agree with all you say.

    Yes, I hope to improve my own VO2 Max through cycling not only in the aerobic zone but in anaerobic zone as well. Garmin tells me, and I don't doubt it, that my VO2 Max is at the lower end for my age and gender. (obviously, theirs is only an estimate, not the result of a lab test, but I am aware of how I feel and don't disagree.

    As a person 71 years of age, I can't use the "HRmax = 220 - age" formula. That formula puts my heart rate max at 149. I have exceeded that during 45-minute swims. So, I use 160 as my HRmax (which might be conservative), and I use the Karvonen method to compute my HR zones, since I have a resting heart rate of 60.

    But as has been pointed out, the OP should focus on health. We all need to pursue physical and mental wellbeing. Don't obsess over losing or not losing weight.