THIS is why HRMs have limited use for tracking calories
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Why not just use the 'average heart rate' and calculate the calories yourself? I find that when I do that, my calculated calories are quite a bit lower than what the HRM calculates.
The formula that I use is (note, for women):
Calories Burned = [(Age x 0.074) -- (Weight x 0.05741) + (Heart Rate x 0.4472) -- 20.4022] x Time / 4.184.
For men:
Calories Burned = [(Age x 0.2017) + (Weight x 0.09036) + (Heart Rate x 0.6309) -- 55.0969] x Time / 4.184.
Those have a built in assumption of VO2max, based on weight and age.
The other version of the formulas the Polar funded study came up with includes a VO2 stat. But then you must get that with some reasonable estimate.
http://www.braydenwm.com/calburn.htm
But then what is left out that other studies have shown is beneficial, is the known HRmax stat. Otherwise, again the formula is assuming 220-age (which they get), and then about 85% of that is lactate threshold, which is assumed to be a certain % of VO2max.
Bunch of assumptions that can be true for population groups, difficult to get down to individual level.
Though I did tweak their formula to account for a different HRmax than assumed, in case you had better estimate or tested.
Azdak would love to run around with a metabolic cart testing someone. Forget the treadmill, he's fast enough to push it around the track now!
Now, where's my calorie burn....0 -
must admit I find it annoying that it keeps telling me each week that I need to take a recovery week but I am training for events so have to hit it hard. I haven't even used the strength training programme built in yet (which may be useless anyway by the indications here lol)
For it to get to the point of recommending a whole week, that must mean you are taking no recovery days.
May want to rethink that approach, as it's the easy day that allows recovery to get stronger from the harder workout.
Exercise tears down. It's the rest for recovery and repair that builds back up.
You might be surprised how much progress you can still make not going full-tilt every day.0 -
must admit I find it annoying that it keeps telling me each week that I need to take a recovery week but I am training for events so have to hit it hard. I haven't even used the strength training programme built in yet (which may be useless anyway by the indications here lol)
For it to get to the point of recommending a whole week, that must mean you are taking no recovery days.
May want to rethink that approach, as it's the easy day that allows recovery to get stronger from the harder workout.
Exercise tears down. It's the rest for recovery and repair that builds back up.
You might be surprised how much progress you can still make not going full-tilt every day.
I think the recovery week is an automatic built in thing as it just popped up at the beginning of a week's targets. I do have rest days - it is the FT80 I have and it sets 3 different levels of intensity each week working in low, moderate and high heart rates with calorie and time targets. I am training for climbing Ben Nevis in just over 2 weeks then have Tough Mudder in 5 weeks so I am doing a real mix of training from walking, hiking, hill/mountain climbing mostly at the weekends and the Tough Mudder bootcamp a couple of days a week and an upper body strength/weights programme 2 to 3 days a week - I typically have one or two rest days a week - but I am finding that even one TM bootcamp is enough to max out the high intensity target - so each week it tells me to take a rest week - it still has targets for medium and low sessions but I am not supposed to do any high intensity. - just doing the stair climber for 25 mins - (which is good prep for mountain climbing) will max it out.
@ Azdak - I know you are not saying HRM's are useless - just that they are not gospel and the data derived from them is all relative (well that is how I am interpreting it anyway lol) it has indicated with no doubt that my resting heart rate has greatly improved and as soon as I stop pushing myself it drops like a stone - which I think is a better indication of fitness I wouldn't be aware of if I wasn't using one.0 -
i actually went to UPMC in the southside of pittsburgh (steelers training facility) to have my Body Fat and my bmr tested
i use that information as my base readins
i think i might be the only person that finds MFP calorie burn estimation to be greatly exaggerated compared to my HRM.
if i did an hour on the elliptical the machine said 700 cals burned, MFP said 956 and my HRM was at about 450.
right now im eating 1700 a day (actually just a smidge under). i do 30 minutes on the arc trainer (510/HR according to my HRM), do my workout (1 body part per weekday) then do 30-45 minutes swimming (logged at 150 cals burned)
unless i have an actual machine attached to me at all time i think you really have to go with the low end of estimates rather than rely on MFP for your cals burned0 -
Ok, so in view of the criticism raised, your suggestion, Azdak, is to estimate a caloric value that might be x % less than TDEE, and tweak as we go, and forget about logging/'eating back' calories. Makes sense, I am fine with that, thank you!
If calories burned isn't helpful for tracking workouts (which I guess people want to do), what do you think about using rate of perceived exertion (or "intensity"), and time?
Seems to me that if you work bloody hard for 40 minutes, it'll add up to something.0 -
Thanks so much for posting this, this is really useful.0
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This whole thread makes me sad. Here I've been feeling so great about logging those exercise calories... I guess the positive is that I never eat them back and I'm losing weight.
I also feel really dumb because I'm a RN with 20 years of experience and when I read this stuff all I hear is "Blah blah blah I need some new shoes..."
My question is - if I'm doing a exercise, let's say a FitnessBlender routine with kettlebells, and the routine lasts 30 minutes, and at the end of it I'm a soaking wet sweat mess and completely out of breath, what percentage of the 460 calories it says I burned do I log? Or should I?
Thanks for the advice and the discussion!0 -
BUMP
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I use my HRM for all of my exercise. I eat at my calorie goal 6 days a week and then I have an open day. Sometimes I go over big time and sometimes not on the open day. I understand what is being said here, but I will continue to use my HRM. Most of my exercise is cardio 6 days a week and I do strength training at least 4 days a week. I have lost 141 lbs since I started and I think I will continue to count weight lifting calories burnt. This is making it too complicated. As an earlier poster said eat right and move and you will have success. Thanks for the post.0
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This whole thread makes me sad. Here I've been feeling so great about logging those exercise calories... I guess the positive is that I never eat them back and I'm losing weight.
I also feel really dumb because I'm a RN with 20 years of experience and when I read this stuff all I hear is "Blah blah blah I need some new shoes..."
My question is - if I'm doing a exercise, let's say a FitnessBlender routine with kettlebells, and the routine lasts 30 minutes, and at the end of it I'm a soaking wet sweat mess and completely out of breath, what percentage of the 460 calories it says I burned do I log? Or should I?
Thanks for the advice and the discussion!
Well, if you don't eat back exercise calories the way MFP is designed, and creating an even bigger deficit and losing muscle mass, then it really doesn't need to be logged except for your record keeping.
Doesn't sound like you'll let it influence the eating goal anyway. So you can make it whatever you want.
And most people could run up stairs and be out of breath, heart pounding, and sweating in probably as little as 2 minutes, so don't let that fool ya too much. Anaerobic exercise must be caught up with eventually.0 -
BUMP0
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This whole thread makes me sad. Here I've been feeling so great about logging those exercise calories... I guess the positive is that I never eat them back and I'm losing weight.
I also feel really dumb because I'm a RN with 20 years of experience and when I read this stuff all I hear is "Blah blah blah I need some new shoes..."
My question is - if I'm doing a exercise, let's say a FitnessBlender routine with kettlebells, and the routine lasts 30 minutes, and at the end of it I'm a soaking wet sweat mess and completely out of breath, what percentage of the 460 calories it says I burned do I log? Or should I?
Thanks for the advice and the discussion!
Well, if you don't eat back exercise calories the way MFP is designed, and creating an even bigger deficit and losing muscle mass, then it really doesn't need to be logged except for your record keeping.
Doesn't sound like you'll let it influence the eating goal anyway. So you can make it whatever you want.
And most people could run up stairs and be out of breath, heart pounding, and sweating in probably as little as 2 minutes, so don't let that fool ya too much. Anaerobic exercise must be caught up with eventually.
My muscle mass is building up quite nicely, thanks!0 -
I'm sorry but this just confused the hell out of me. So are you saying I shouldn't use the calories burned that my HRM shows when tracking exercise.
Depends on the exercise. The OP states: <SNIP>The entire concept of using heart rate as means of estimating exercise calories is based on the relationship between heart rate (HR) and oxygen uptake (VO2) during steady-state aerobic exercise.
During steady-state aerobic exercise, there is a relatively consistent relationship between HR and VO2.
Visualize a car equipped with a tachometer. Cruising at a constant speed on the open highway one could more accurately estimate fuel expenditure per mile merely by monitoring the tach.
Not so in city driving because of inconsistent demands on the power plant. (do I make sense or do I only think I do? LOL)
I think this is a good analogy
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Your HRM's manual will say it's meant only for steady state cardio because HRMs use a formula made specifically for those exercises and those exercises only.
So if you look at the chart, you'll see that using a HRM for anything will give you a falsely elevated calorie burn. I wear mine during weight lifting (because I use it for my warm up and to do cardio afterward) and it will easily tell me I burned 400 cals in 30 minutes, when the reality is I probably burned 100 or less.
My Polar RCX3 has options for biking/running and other. Whenever I go to the gym to lift weights, I hardly burn any calories. Last night it was something like 25 in a 15-20 min session. Then I switched to the row machine, then onto the bike and burned a reasonable amount (but much less than what the machines themselves said).
I have not found the Polar to be far off. If anything, it is always lower than either MFP or whatever is built into the machine I am working on.0 -
bump to read later0
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My Polar RCX3 has options for biking/running and other. Whenever I go to the gym to lift weights, I hardly burn any calories. Last night it was something like 25 in a 15-20 min session. Then I switched to the row machine, then onto the bike and burned a reasonable amount (but much less than what the machines themselves said).
I have not found the Polar to be far off. If anything, it is always lower than either MFP or whatever is built into the machine I am working on.
Do you update the VO2max stat on there after changing weight loss on the device?
Merely losing weight but keeping the same fitness level actually raises VO2max stat.
Polar's FAQ also says do the test first thing in morning after a rest day, otherwise you can mess up the analysis, which is mostly just getting the restingHR, but still.
If the HRM had an old VO2max stat, which is lower than current real value, it'll see low HR as low effort as low calorie burn, which is not correct.
Because rowers and bikes with electric resistance aren't too bad, it usually knows the watts expended, and watts is energy, and converts to calories.
Of course for both of those, personal efficiency can have a decent impact, compared to walking or slower jogging that has much less variance.0 -
Really good post.
Trying to futilely estimate calorie burns was frustrating for me anyway, so I'm glad I'm sticking with the TDEE - 20% method. I'm really glad you brought this up though. It was a really eye-opening read.0 -
good info! I am going to finish reading through this tomorrow.0
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The entire concept of using heart rate as means of estimating exercise calories is based on the relationship between heart rate (HR) and oxygen uptake (VO2) during steady-state aerobic exercise.
During steady-state aerobic exercise, there is a relatively consistent relationship between HR and VO2. Working at "X%" of HRmax usually means that one is working at "Y%" of VO2 max. If you know your VO2max and your true HRmax, then you can use that relationship to estimate VO2 during exercise--which means that you can also estimate calories, since calories burned is based on VO2 times body weight.
Once you leave the realm of steady-state aerobic exercise, however, accuracy of HRMs deteriorates rapidly. To understand why, you need to look at this chart:
The chart shows the percentage of VO2max that occurs when heart rate is at 85% of max HR reserve during various activities.
As you can see, it's quite a spread. The red bar is the heart rate--here, set at 85% max HR reserve. The blue bar is steady-state cardio. As you can see, steady-state cardio is the closest match.
While a heart rate of 85% of max corresponds to 75%-80% VO2 max during steady-state cardio, by the time you get to lifting heavy weights, that same heart rate of 85% of max corresponds to only 21% of VO2max.
The HRM doesn't know the difference--it is programmed to display a calorie number based on whatever heart rate it senses. It cannot detect the type of activity. This is why HRM calorie numbers for many non-steady-state-aerobic activities are useless.
The same situation is also true during thermal stress. Heart rate is elevated, while VO2 is not. That's why the inflated calorie claims for activities such as hot yoga are such nonsense.
For some reason, even though this is exercise physiology 101, many so-called "fitness experts" do not understand this. Now that you do, this is one way to evaluate the credibility of a trainer or fitness author. If they say something like "lifting weights can be cardio if you move quickly between exercises to keep your heart rate up", you know you are listening to someone with a serious deficit in their knowledge base--and you'll have to wonder what else they don't know.0 -
So if an HRM isn't good for interval training, isn't good for lifting weights, and is only good for steady state cardio, then what's the purpose of using one? I thought about getting one but now I'm reconsidering.
I currently jog for 3 minutes and walk for 2 for 2 miles....building up for a continuous run of the whole 2 miles. I also do P90X Lean schedule on alternate days of running. Will an HRM work for calculating calories for this or do these 2 types of exercise fall into the ones that render it useless?0 -
Great Thread - Thanks for the info Adzak!0
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As mentioned HRM's are limited to steady state cardio for accuracy. Easiest way I explain it to clients is one could wear an HRM to a scary movie. Heart rate increase in it obviously will increase and maybe stay throughout the whole movie. Does that mean just sitting there watching it means you burn more significantly more calories compared to watching a movie that isn't scary? Think about it.So if an HRM isn't good for interval training, isn't good for lifting weights, and is only good for steady state cardio, then what's the purpose of using one? I thought about getting one but now I'm reconsidering.
I currently jog for 3 minutes and walk for 2 for 2 miles....building up for a continuous run of the whole 2 miles. I also do P90X Lean schedule on alternate days of running. Will an HRM work for calculating calories for this or do these 2 types of exercise fall into the ones that render it useless?
Estimation of calories burned is just that, an estimation. Being consistent with it will give one a sense of what intake they need to adjust to for energy needs.
A.C.E. Certified Personal/Group FitnessTrainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 30 years and have studied kinesiology and nutrition0 -
There's always someone on here just waiting to burst a person's balloon animals. If you people spent half as much time trying to come up with a new invention as you do trying to kill the inventions already created (i.e., HRM's), this world wouldn't be such a crappy place.0
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As mentioned HRM's are limited to steady state cardio for accuracy. Easiest way I explain it to clients is one could wear an HRM to a scary movie. Heart rate increase in it obviously will increase and maybe stay throughout the whole movie. Does that mean just sitting there watching it means you burn more significantly more calories compared to watching a movie that isn't scary? Think about it.So if an HRM isn't good for interval training, isn't good for lifting weights, and is only good for steady state cardio, then what's the purpose of using one? <<snipped>>
Estimation of calories burned is just that, an estimation. Being consistent with it will give one a sense of what intake they need to adjust to for energy needs.
^^this good analogy!0 -
So if an HRM isn't good for interval training, isn't good for lifting weights, and is only good for steady state cardio, then what's the purpose of using one? I thought about getting one but now I'm reconsidering.
I currently jog for 3 minutes and walk for 2 for 2 miles....building up for a continuous run of the whole 2 miles. I also do P90X Lean schedule on alternate days of running. Will an HRM work for calculating calories for this or do these 2 types of exercise fall into the ones that render it useless?
Jogging and then walking isn't the type of interval training being referred to. The variance in your HR between those 2 probably isn't that great.
HIIT type, where you push anaerobically (just like lifting) for only 15-45 seconds, and then recover from 45-135 seconds, causes total non-steady state, and probably variances of 50-60 bpm HR.
Other interval types are also totally anaerobic to a lesser degree for maybe upwards of 1-2 minutes, then a 1-2 min recovery.
Those type being anaerobic and non-steady state will be inflated, the second not as bad. Because while you do have decent periods of bad estimates, it's balanced by periods of good estimates.
What you are doing with running and walking, no nearly as bad.
P90X is totally non-steady state, and many parts of it are anaerobic.
What you'll notice if you watch HR when doing a cardio workout, if you increase the workload (faster, more incline, ect) the HR will of course go up as expected. But it was an overshoot you might say for what was required. So you keep going for 2-4 minutes, and it'll drop back down to what is really needed for that workload, perhaps 5-10 bpm slower.
So now picture a workout where you never keep the same workload for 2-4 minutes, the HR never lowers back down to what is really needed for that level of work - in other words it's always inflated by 5-10 bpm. And that's for aerobic cardio. That's why it's going to be inflated.
Include lifting where the HR increase isn't even for the purpose of required oxygen, really inflated.
You'll get better calorie count using the MFP estimate if you truly match the speed given in the description (on avg) and did it flat, which is what it's based on.
Otherwise, use this. MFP and HRM would give you a gross figure, but use NET here to log and eat it all back.
http://www.exrx.net/Calculators/WalkRunMETs.html
But you can use the HRM to get a good idea you are still pushing as hard as you need to.
For instance, if after couple months you are still doing the same pace routine, but the avgHR dropped 20 bpm, it just got easier for your heart muscle. If you weigh the same it's the same calorie burn and workload for your other muscles at least, but that's likely not the case, you probably weigh less and should be going faster so the muscles get the same workout. And actually, for the heart to get a better workout, probably need to go even faster still.0 -
This ^^^^ the post above - Very good explanation and totally logical! :drinker:0
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There's always someone on here just waiting to burst a person's balloon animals. If you people spent half as much time trying to come up with a new invention as you do trying to kill the inventions already created (i.e., HRM's), this world wouldn't be such a crappy place.
Pardon us for helping people understand better the tool they are using doesn't do exactly what they thought it did.
And how in the world are we killing a HRM, that would be Heart Rate Monitor in case you didn't know, by talking about something it was never intended to do in the first place, estimate calorie burn.
Go drive your car in a lake. oh wait, you mean it's not a boat!0 -
So if an HRM isn't good for interval training, isn't good for lifting weights, and is only good for steady state cardio, then what's the purpose of using one? I thought about getting one but now I'm reconsidering.
I currently jog for 3 minutes and walk for 2 for 2 miles....building up for a continuous run of the whole 2 miles. I also do P90X Lean schedule on alternate days of running. Will an HRM work for calculating calories for this or do these 2 types of exercise fall into the ones that render it useless?
Jogging and then walking isn't the type of interval training being referred to. The variance in your HR between those 2 probably isn't that great.
HIIT type, where you push anaerobically (just like lifting) for only 15-45 seconds, and then recover from 45-135 seconds, causes total non-steady state, and probably variances of 50-60 bpm HR.
Other interval types are also totally anaerobic to a lesser degree for maybe upwards of 1-2 minutes, then a 1-2 min recovery.
Those type being anaerobic and non-steady state will be inflated, the second not as bad. Because while you do have decent periods of bad estimates, it's balanced by periods of good estimates.
What you are doing with running and walking, no nearly as bad.
P90X is totally non-steady state, and many parts of it are anaerobic.
What you'll notice if you watch HR when doing a cardio workout, if you increase the workload (faster, more incline, ect) the HR will of course go up as expected. But it was an overshoot you might say for what was required. So you keep going for 2-4 minutes, and it'll drop back down to what is really needed for that workload, perhaps 5-10 bpm slower.
So now picture a workout where you never keep the same workload for 2-4 minutes, the HR never lowers back down to what is really needed for that level of work - in other words it's always inflated by 5-10 bpm. And that's for aerobic cardio. That's why it's going to be inflated.
Include lifting where the HR increase isn't even for the purpose of required oxygen, really inflated.
You'll get better calorie count using the MFP estimate if you truly match the speed given in the description (on avg) and did it flat, which is what it's based on.
Otherwise, use this. MFP and HRM would give you a gross figure, but use NET here to log and eat it all back.
http://www.exrx.net/Calculators/WalkRunMETs.html
But you can use the HRM to get a good idea you are still pushing as hard as you need to.
For instance, if after couple months you are still doing the same pace routine, but the avgHR dropped 20 bpm, it just got easier for your heart muscle. If you weigh the same it's the same calorie burn and workload for your other muscles at least, but that's likely not the case, you probably weigh less and should be going faster so the muscles get the same workout. And actually, for the heart to get a better workout, probably need to go even faster still.
Thanks!0 -
Thanks!
I forgot to get in to your question of why you'd want to use a HRM if calorie count is possibly so bad and invalid for some workouts.
As you probably got the point - HRM main purpose is exactly what the name says - monitoring HR.
So especially intervals is it useful.
For really getting a benefit from most intervals, it must be so much of a workout for the heart and muscles, so it needs to reach a certain level.
If it doesn't, you don't get the improvements that workout could provide. You'll get some, but possibly not the same, nor not nearly as much as could have been gained.
Might view it as lifting. If you can squat 200 lbs 3 x 8, but you proceed to do your workouts with 50 lbs - gonna see much of any improvement?
It will only become difficult, possibly, if your muscles lose their strength and that level is now maintaining.
And even in lifting with that example, HR would show up that fact.
200 lb you'd probably end up pushing the HR in to the anaerobic HR zone.
50 lb might cause some spikes, but not nearly as high.
Now anyone could read their body for that extreme difference, and know why one is harder.
But it also can confirm if you are lifting on tired muscles, not getting as good a workout as you could. If your muscles are so tired that they can't push the HR as high as normal, you missed sleep, or perhaps that cardio workout day before took too much out of ya, ect. Now you know that if lifting was more important, don't do those things that impact it.
Same way the vast majority think they are doing HIIT just because they are pushing themselves hard. Doing that tired and fresh is very different, and HR will show up the difference.
And HIIT only has it's intended benefit if you reach that anaerobic lifting-like HR levels. If you don't, then you aren't getting the benefit you think you are. Even if you feel like you are pushing as hard as you think.
Might as will do SIT or regular intervals and get a different but still beneficial workout for the time and effort given.
And just as intervals provide a benefit by going hard and then easy, so that hard is really hard and see body improvement, and easy allows recovery, HRM can confirm your workout days follow the same method.
Hard days can truly be hard, when easier days are in between. So HRM can confirm that you keep the load light, but still active, on another workout.
For years that was called Active Recovery HR zone, but lately it's been called by the fad name fat-burning zone. Still a totally valid and useful training zone, increase blood flow, use the muscle, but don't add another load the body must recover from while it's already trying to recover from a hard workout day before.0 -
Pardon us for helping people understand better the tool they are using doesn't do exactly what they thought it did.
And how in the world are we killing a HRM, that would be Heart Rate Monitor in case you didn't know, by talking about something it was never intended to do in the first place, estimate calorie burn.
Go drive your car in a lake. oh wait, you mean it's not a boat!
Remind me to scare you from the gutter, grampa.0
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