confused about calorie burn

racataca

I've read my share of posts on this subject, and it seems like everyone thinks that the best reading to go by is a Heart Rate Monitor with a chest strap. The general consensus is that MFP estimates too highly and machines are not accurate enough.

I also read posts saying that it is "highly unlikely" that a person would burn 400 calories in 1/2 hour doing spinning/zumba/kickboxing/anything and that's where I'm confused.

I wear a HRM with a strap when I work out, and generally when I go to classes, it reads a burn of between 700-800 calores in an hour, with the only exception being Group Power - a lifting class where it reads ~450 calories an hour burned. I work hard and I leave energized, but I never feel like I'm going to pass out or that I've pushed myself too far.

So if the general consensus is that HRM are the best to obtain an accurate reading, but also that it's "highly unlikely" that a person is going to burn that quantity of calories, then what am I supposed to expect?

3dogsrunning

People put way too much faith behind HRMs. I'm not saying they are useless, but they aren't necessarily the most accurate.
They are ideally used for steady state cardio. There are a number of things that can affect the accuracy.
Here's a great link on HRMs. (Scroll down for two more links tht may be useful)

http://www.myfitnesspal.com/topics/show/773451-is-my-hrm-giving-me-incorrect-calorie-burn

racataca

What I'm reading there is that major confounding factors to a HRMs accuracy are things like interference of machines, as well as exercising in a non-steady aerobic state (so lifting), and other factors like temperature, caffeine intake, and mood (which I feel as though the latter two must have a pretty minimal effect especially if my resting heart rate is constant for the most part).

So for a highly aerobic class like kickboxing, done away from the vicinity of machine interference, in a temperature/humidity controlled building, I'm still not seeing how a HRMs accuracy would be affected, and therefore why it would be unlikely that I'd burn that number of calories in an hour?

What would you suggest is the most accurate monitor of calories burned, if not a HRM? I don't eat the majority of my calories back anyway, but there's a difference between eating 200 of 700 burned back, and eating 200 of what is actually 150 burned back.

vjohn04

I burn around 550-590 kcal / hr at my KO Heavy Bag class... it's very cardio intensive.

Considering I burn 300 or so running for a half hour, I would say that it's pretty accurate for me. I am exerting significant energy at the Heavy Bag class.

3dogsrunning

I believe they are most accurate at steady state cardio. And that the fitter you are the more inaccurate it might be. Things like intervals can increase the inaccuracy. I have not done Zumba so I don't know whether it would be consistent HR or not.


The problem is there is no "Accurate" way. MFPs table are based off of formulas based on "averages". So are HRMs.

Everything is an estimate. BMR, TDEE, the calories you log, the calories you burn.
If you want to log 700 calories for a Zumba class, go ahead. If you lose weight, perfect. If you don't, try lowering it a bit.


ETA - even with MFP estimates there shouldn't be such a huge discrepancy as 200-700. Honestly, an hour of Zumba should burn more than 200.

denezy

Calories burnt also depend on your weight and age.

I am 33 f, about 200 lbs, and in a spin class burn about 500-600 calories in 60 minutes. Kick boxing I am a bit higher, but never much above 650. Body Pump I burn about 400.

I get my heart rate quite high (180+) during those classes, but have a very low resting heart rate (44 before getting up in the morning).

I see people on my friends list here burning 1100 calories with a HRM during an hour of running or something... and I don't know how they do it.

vjohn04

Calories burnt also depend on your weight and age.

I am 33 f, about 200 lbs, and in a spin class burn about 500-600 calories in 60 minutes. Kick boxing I am a bit higher, but never much above 650. Body Pump I burn about 400.

I get my heart rate quite high (180+) during those classes, but have a very low resting heart rate (44 before getting up in the morning).

I see people on my friends list here burning 1100 calories with a HRM during an hour of running or something... and I don't know how they do it.

Yikes! I work out pretty hard..... I've NEVER burnt 1100 calories in one hour.
In fact, I think the most I've burnt in a day for exercise was like 960 and that was a half hour running, and then an hour of jazzercise / boxing / something else.

Mokey41

Your burn will depend on your age, sex, weight and the intensity of your workout. I'm 55, female and weigh about 118 lbs. I burn about 600 calories per hour running. Nothing else I do comes close to that. It's not unlikely to burn 1,000 calories running if you are a larger, young man!

WaterBunnie

I see people on my friends list here burning 1100 calories with a HRM during an hour of running or something... and I don't know how they do it.

Perhaps they are a lot heavier than you?

3dogsrunning

Calories burnt also depend on your weight and age.

I am 33 f, about 200 lbs, and in a spin class burn about 500-600 calories in 60 minutes. Kick boxing I am a bit higher, but never much above 650. Body Pump I burn about 400.

I get my heart rate quite high (180+) during those classes, but have a very low resting heart rate (44 before getting up in the morning).

I see people on my friends list here burning 1100 calories with a HRM during an hour of running or something... and I don't know how they do it.

I would have to run a 6 minute mile (I wish!) to burn 1100 calories at my weight.
But a 200lb person can burn 1100 in 60 minutes at an 8m/m pace.


The two biggest factors in calorie burning is weight and intensity.

3RachaelFaith3

Calories burnt also depend on your weight and age.

I am 33 f, about 200 lbs, and in a spin class burn about 500-600 calories in 60 minutes. Kick boxing I am a bit higher, but never much above 650. Body Pump I burn about 400.

I get my heart rate quite high (180+) during those classes, but have a very low resting heart rate (44 before getting up in the morning).

I see people on my friends list here burning 1100 calories with a HRM during an hour of running or something... and I don't know how they do it.

yep, also subtract your BMR.

DebbieLyn63

I just did a fairly intense bike ride in 48 minutes burned 358 calories. Average HR 133 and Max HR 152. I am a 49 yo female, 5'6" and 198. This was recorded on a Polar FT4 HRM.
That is a fairly normal burn rate for me these days. When I first started riding, I was doing good to get my HR up to 120, and it took me an hour to burn 300 calories. However, my stationary bike computer and MFP would tell me I was burning over 600 per hour.

So if you are getting your heart rate up high, near your max, and keeping it there for an hour, it is possible for you to be burning 600-700 cals per hour. I still find it hard to believe many people can hit 1100 in an hour tho. My husband doesn't hit that rate even when he is racing mountain bikes and topping his HR out at 200bpm. But who knows.

DebbieLyn63

I've read my share of posts on this subject, and it seems like everyone thinks that the best reading to go by is a Heart Rate Monitor with a chest strap. The general consensus is that MFP estimates too highly and machines are not accurate enough.

I also read posts saying that it is "highly unlikely" that a person would burn 400 calories in 1/2 hour doing spinning/zumba/kickboxing/anything and that's where I'm confused.

I wear a HRM with a strap when I work out, and generally when I go to classes, it reads a burn of between 700-800 calores in an hour, with the only exception being Group Power - a lifting class where it reads ~450 calories an hour burned. I work hard and I leave energized, but I never feel like I'm going to pass out or that I've pushed myself too far.

So if the general consensus is that HRM are the best to obtain an accurate reading, but also that it's "highly unlikely" that a person is going to burn that quantity of calories, then what am I supposed to expect?

What brand of HRM do you use? I have heard that hands down, Polar is the best and most accurate, especially for women. I have heard that TImex can give women an inflated calorie burn. Don't know about any of the others. If you are using a Polar, I would say that it was accurate, and go with those numbers.

ETA- I did burn almost 400 calories in a half hour of Wii boxing one day, but I hit my top max HR of 171 and averaged over 150 the whole time. Thought I was going to die!

Azdak

First of all, calories burnt depends on weight x intensity. That's it. HRMs need more information (age, height, etc) but that is because they cannot measure workload--and the the algorithms they use need more data points.

But that's a math issue to compensate for the inherent inaccuracy of the HRM method, not a calorie issue. (In other words, if you can accurately measure the workload --e.g. speed and distance, watts, etc--all you need is body weight and you can estimate calories with reasonable accuracy. The other factors--age, gender, heart rate--are not necessary).

There are three sources of inaccuracy/variance with HRM calorie estimates:

1. Not knowing true HR max.

2. Not knowing VO2 max

3. Using the HRM for activities other than steady-state aerobics.

Most often, when people get high calorie readings with an HRM, it's because they have a naturally higher-than-average max heart rate. For example, one's calculated 70% heart rate might be 160, but their true 70% heart rate is 185. The HRM doesn't know the difference--it is a dumb tool programmed to spit out numbers based on assumptions--so it assumes that you are working at 90%-100% (or higher).

Anyone who gets a new heart rate monitor MUST spend some time with their device, observing their exercise heart rate under a variety of workout conditions, and comparing their heart rates during aerobic exercise with feelings of perceived exertion. You will eventually get a feel for your own heart rate "scale" and then you can adjust the settings to make them more suitable for your physiology.

BTW, burning 400 calories in 1/2 is not "highly unlikely". It's not necessarily easy, but it all depends on weight and fitness level. In a Zumba class, you'd probably have to be well over 200lbs and pushing it to get that high, but a 174lb person running 6.0 mph would hit that number.

SarahRea32

Thanks for this thread guys, was thinking about posting something similar as I often see people logging burns of 1000+ for one example for an hour of 'dancing', yet my "high intensity interval training" for 30 mins comes out (according to MFP) at about 300! Have been thinking about a HRM as I don't trust the values on MFP or the machines at the gym. If any one else has any comments about good HRMs and if they think they are worth the investment I would appreciate it. Thanks

katy_trail

http://whatscookingamerica.net/Information/CalorieBurnChart.htm

This is a good comparison chart. Obviously, too time consuming to use everyday, but
just by glancing at your normal activity vs higher or lower intensity you can increase or decrease your burn rate.

One of the biggest differences between calorie bun numbers is if they include what you already burn just walking around,
breathing. If they don't include that, the count is obviously lower, but more likely more accurate.
Estimating what you burn just existing is a guess. a shot in the dark. but saying what you are burning now, isn't.

my fav. cal. burned calculator. it is the most extensive I've found, and over the years they've added many more activities.
http://www.caloriesperhour.com/index_burn.php

quote from the calories per hour page:
How the Activity Calculator Works
Calories Burned, BMI, BMR & RMR Calculator

Most of the data used by calories burned calculators has been collected by measuring the amount of oxygen consumed performing each activity. A number, called a MET (Metabolic Equivalent), is assigned to each activity to indicate its level of intensity.

An activity with a MET of one corresponds to a person's RMR (Resting Metabolic Rate), the rate at which they would burn calories resting. Other activities are assigned MET values to indicate their intensity level relative to RMR.

For example, driving a car has a MET of two and playing water polo has a MET of ten. This indicates that you would burn twice as many calories driving a car as you would sitting still, and ten times as many playing water polo.

Based on the above, it would appear that the most accurate way to calculate calories burned would be to use the number of METs assigned to the activity you select, your RMR, and the length of time you performed the activity. However, in most cases the MET data was collected using a constant based on weight alone rather than RMR. Therefore for consistency we also use a constant based on your weight rather than RMR.

Important Note

Calories burned calculations reflect the total number of calories burned during the period of time calculated. Therefore when calculating how many calories you need or burn in a day, do not add your RMR or BMR.

Azdak

http://whatscookingamerica.net/Information/CalorieBurnChart.htm

This is a good comparison chart. Obviously, too time consuming to use everyday, but
just by glancing at your normal activity vs higher or lower intensity you can increase or decrease your burn rate.

One of the biggest differences between calorie bun numbers is if they include what you already burn just walking around,
breathing. If they don't include that, the count is obviously lower, but more likely more accurate.
Estimating what you burn just existing is a guess. a shot in the dark. but saying what you are burning now, isn't.

my fav. cal. burned calculator. it is the most extensive I've found, and over the years they've added many more activities.
http://www.caloriesperhour.com/index_burn.php

quote from the calories per hour page:
How the Activity Calculator Works
Calories Burned, BMI, BMR & RMR Calculator

Most of the data used by calories burned calculators has been collected by measuring the amount of oxygen consumed performing each activity. A number, called a MET (Metabolic Equivalent), is assigned to each activity to indicate its level of intensity.

An activity with a MET of one corresponds to a person's RMR (Resting Metabolic Rate), the rate at which they would burn calories resting. Other activities are assigned MET values to indicate their intensity level relative to RMR.

For example, driving a car has a MET of two and playing water polo has a MET of ten. This indicates that you would burn twice as many calories driving a car as you would sitting still, and ten times as many playing water polo.

Based on the above, it would appear that the most accurate way to calculate calories burned would be to use the number of METs assigned to the activity you select, your RMR, and the length of time you performed the activity. However, in most cases the MET data was collected using a constant based on weight alone rather than RMR. Therefore for consistency we also use a constant based on your weight rather than RMR.

Important Note

Calories burned calculations reflect the total number of calories burned during the period of time calculated. Therefore when calculating how many calories you need or burn in a day, do not add your RMR or BMR.

In theory, using METs is one of the more accurate ways to estimate calories. Unfortunately, the accuracy of MET values for various activities is all over the map. The MFP calorie numbers are largely derived from MET value databases and we can easily see how far off those numbers are.

petepie2

I just received a Polar FT4 for Christmas. This morning I ran 5 miles in 53 minutes, plus a 3 minute walk to and from the track. My HRM said I burned 610 calories. My average HR was in the 160s with a max of 178. I'm 5'4" and weigh 124 lbs. So, according to my HRM, the values from MFP underestimate how many calories I burn running.

Azdak

I just received a Polar FT4 for Christmas. This morning I ran 5 miles in 53 minutes, plus a 3 minute walk to and from the track. My HRM said I burned 610 calories. My average HR was in the 160s with a max of 178. I'm 5'4" and weigh 124 lbs. So, according to my HRM, the values from MFP underestimate how many calories I burn running.

Unless you have your Polar set up incorrectly. There are a number of variables involved in improving the accuracy of HRMs. It is wrong to automatically assume that because the HRM number is different, it is more accurate.

http://www.myfitnesspal.com/blog/Azdak/view/new-hrm-how-to-make-the-calorie-estimate-more-accurate-183102

staceypunk

I just received a Polar FT4 for Christmas. This morning I ran 5 miles in 53 minutes, plus a 3 minute walk to and from the track. My HRM said I burned 610 calories. My average HR was in the 160s with a max of 178. I'm 5'4" and weigh 124 lbs. So, according to my HRM, the values from MFP underestimate how many calories I burn running.

Unless you have your Polar set up incorrectly. There are a number of variables involved in improving the accuracy of HRMs. It is wrong to automatically assume that because the HRM number is different, it is more accurate.

http://www.myfitnesspal.com/blog/Azdak/view/new-hrm-how-to-make-the-calorie-estimate-more-accurate-183102

Thanks Azdak, your blog is helpful. I just got the PolarF4 for Christmas and it says I burn about 330 calories doing phase 3 of Jiliian Micheal's Body Revolution (35 minutes). There is a huge difference in intensity from phase 2 to 3 so I kind of took that at face value. I like what you said about paying attention to the heart rate number when you know you are truly exerting and reprogramming your heart max on the monitor. Thanks!