HRM Carories... Is this possible?

Taka75

My friend gave me her old HRM a couple of days ago as she uses a better one now. I've set it up with my details and tried it out today when I went to my ice skating class and practice. Ermmmm... it said I had burned 1434 kcals! :noway: Is that even possible? :huh:

Its a polar A5 HRM. I am very unfit (though improving!), weight 19 st 7.4 lbs (273.4lbs) and was skating for just short of 2 hrs (This includes warming up and down time - apparently 1hr 40 mins of exercising was "in zone", aveage heart rate of 137.) The lesson was 45 mins and is quite stop/start, and massively varies in intensity, then the practice was pretty variable too depending on the moves I was working on.

Is the monitor likely to be correct?


If it is correct... how on earth do I eat back that level of exercise calories - including exercise cals MFP says I need to eat 3094 cals today! Eeeeeek! :noway: I know I'm ravenous for ~24 hrs after skating but still thats a lot! :huh:

Thanks in advance! :flowerforyou:

EDIT: Ooops got calories wrong in the title! Sorry! :blushing:

TabiHerbalifeCoach

double check your stats, and if they are correct i would trust it. but if youre still leary find your local polor distributior/ maintance store and they should be able to check it out for you.

MisdemeanorM

I burn 700 an hour in Zumba if I can keep my heart rate up... and I would have a lower burn count since I am 160 - so it is possible that you burned 700 an hour if your heart rate was up. And regarding eating them all back - if it is once in a while, don't worry about it. I was way under on cals yesterday, but over the day before - I'm not worried that my body will think I am starving because there is no consistant shortage of calories.

DJH510

Anything other than the most expensive, advanced HRM's are quite inaccurate, and even the best ones only provide a fairly educated guess at the number of calories burned. Remember, the purpose of a heart rate monitor is to monitor your heart rate for training purposes. Predicting calories burned is not what they are designed and built for and so the accuracy is often quite weak. That amount does sound like quite a lot, I would suggest it was closer to half that amount, but without knowing more about the details of the activity it is obviously hard to tell!

DrBorkBork

Sounds about right to me! A good workout will have you burning about 100 cals every 10 mins. If you did almost 120 mins of hard exercise, then that's about 1200 cals. Pretty exciting!

poustotah

I have to agree with DJH. I use the Polar F6 and I keep my heart rate up when I'm on the treadmill, kickboxing, or in spin. I use it all the time and the calories on it are grossly inaccurate. According to the HRM, I had lost 300 calories on the elliptical for 30 minutes but I lost 460 calories weightlifting for 30 minutes. There's absolutely no way when my heart rate was at 160 the entire time I was on the elliptical.

Taka75

Thanks for replying! My stats in the machine are definitely correct.

I realise that measuring the calories is not really what a HRM is for. I wanted one to help myself to exercise more effectively and to guage any improvements in my fitness. I'm not very fit but starting to noticably improve from a very low level of fitness.

The skating class is very mixed - some parts are very intense where I am sweating, wearing a tshirt (no jumper) in a cold ice rink (HR was saying ~167 at this point and flashing to say I was over my upper limit.) - sort of similar in intensity to very fast power walking - I was doing this for 30 mins plus. Some parts are more sedate but most of it really works out my thights, abs and glutes.

I feel VERY, very hungry afterwards which I don't when I am doing my pilates or fitness DVDs. I'll maybe try just eating back half of the calories if it is not overly accurate on the calorie measuring. The interest in the calories number was more just so I have something a little bit more accurate to put into MFP!

Thanks!

Cina04

I would believe it!

when I wear my HRM I usually update it about every 5 to 10 mins or when my HR increases or decreases so I can get an accurate calories burn totally

MisdemeanorM

Polar has a feature in their HRMS too that you can base your workout on your HR for that day - so it can take minor shifts into account. It has a 5 min warm up where you keep your HR in a certain zone for each of the minutes - I am impatient so I don't do it, and I never learned how to really do it, but it looks really simple and might give a more accurate reading.

dj_stevie_c

Yeah you burn 500-800 cals per hour depending on what excersize you're doing. As for eating them back, just have a sensible meal and try to take on a little extra protein maybe. Don't stuff yourself silly but don't starve yourself you'll be fine.

Edit: Don't forget in the cold your body is working a little harder in order to try and keep you warm as well

rose1617

I have to agree with DJH. I use the Polar F6 and I keep my heart rate up when I'm on the treadmill, kickboxing, or in spin. I use it all the time and the calories on it are grossly inaccurate. According to the HRM, I had lost 300 calories on the elliptical for 30 minutes but I lost 460 calories weightlifting for 30 minutes. There's absolutely no way when my heart rate was at 160 the entire time I was on the elliptical.

That actually makes sense. Your heartrate is up around 70% if you are weight-lifting heavily.
If you are on the elliptical, you'd need to keep your heart rate up and not let it dip the entire time you're on it to maintian the same HR at the same level as heavy weightlifting. If you're not lifting heavily, then yes it's wrong.

Nina74

:sad: I have no idea any more. I got the Polar FT4 the other day and it said I burned 100 calories after working out heavy for 30 mins, so that can't be right either (I weight 299). I am utterly lost as to whether it is the unit, me, both, etc.