Is my HRM off? Am I not getting enough calories?

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Hello all,

So I used my new Polar FT4 hrm at the gym yesterday and the calories burned seemed quite off. For 20 minutes on the elliptical, the hrm told me that I burned about 400 calories, but the machine itself said I burned 236 calories. Which should I go by?

My second issue: If the hrm is accurate, and I have been using the estimations from the machines for the past few weeks, I am concerned I was not eating enough of my calories back and sending my body into starvation mode which inhibits fat loss. Could that be possible!

Thanks so much :)

Replies

  • mlima14
    mlima14 Posts: 112 Member
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    I have the same question. I bought the Adidas Coach Pacer, and it tells me a way higher reading than the machine also. I try not to eat back my calories (doesn't always happen :ohwell: ), just in case.
  • albayin
    albayin Posts: 2,524 Member
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    After weighing every bite of my food for over a week, I become to realize that I would never undereat: it's just too easy to underestimate how much I put in my mouth...

    But everybody is different. My body is super efficient and doesn't waste any single piece food and convert it to energy. :) So I don't worry about me going into this so called "starvation mode". But again that's just me~
    :flowerforyou:
  • QuietBloom
    QuietBloom Posts: 5,413 Member
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    Hello all,

    So I used my new Polar FT4 hrm at the gym yesterday and the calories burned seemed quite off. For 20 minutes on the elliptical, the hrm told me that I burned about 400 calories, but the machine itself said I burned 236 calories. Which should I go by?

    My second issue: If the hrm is accurate, and I have been using the estimations from the machines for the past few weeks, I am concerned I was not eating enough of my calories back and sending my body into starvation mode which inhibits fat loss. Could that be possible!

    Thanks so much :)

    Did you enter your information into your heart rate monitor? It does sound like it is way off. Mine has a place for me to enter my stats, but it still over calculates my burns. I ended up using the website to calculate my gross, and then my net burn. Shapesense.com
  • SLLRunner
    SLLRunner Posts: 12,942 Member
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    Hello all,

    So I used my new Polar FT4 hrm at the gym yesterday and the calories burned seemed quite off. For 20 minutes on the elliptical, the hrm told me that I burned about 400 calories, but the machine itself said I burned 236 calories. Which should I go by?

    My second issue: If the hrm is accurate, and I have been using the estimations from the machines for the past few weeks, I am concerned I was not eating enough of my calories back and sending my body into starvation mode which inhibits fat loss. Could that be possible!

    Thanks so much :)
    You are a twenty year old guy, around 215 pounds. I have no doubt that your heart rate monitor is more accurate than the 236 the elliptical machine gave you.

    Keep up the good work.

    Yes, eat your exercise calories back. However, I would not worry about sending your body into starvation mode.
  • editorgrrl
    editorgrrl Posts: 7,060 Member
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    Everybody's different, and weight loss takes a whole lot of trial & error to find what works for you. Trust your HRM for two weeks, then reevaluate: did you lose, maintain, or gain?

    Read this: http://www.myfitnesspal.com/topics/show/1080242-a-guide-to-get-you-started-on-your-path-to-Sexypants
  • 3dogsrunning
    3dogsrunning Posts: 27,167 Member
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    That is exceptionally high for 20 minutes on an elliptical.

    HRMs are not infallible, there are many things that can cause incorrect readings.

    Check out this links

    http://www.myfitnesspal.com/topics/show/774337-how-to-test-hrm-for-how-accurate-calorie-burn-is
    http://www.myfitnesspal.com/topics/show/548645-setup-polar-hrm-for-more-accurate-calorie-burn-for-known-bmr


    When in doubt I always go for the lower number.

    Eating 200 calories less isn't going to put you into starvation mode.
  • 3dogsrunning
    3dogsrunning Posts: 27,167 Member
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    Hello all,

    So I used my new Polar FT4 hrm at the gym yesterday and the calories burned seemed quite off. For 20 minutes on the elliptical, the hrm told me that I burned about 400 calories, but the machine itself said I burned 236 calories. Which should I go by?

    My second issue: If the hrm is accurate, and I have been using the estimations from the machines for the past few weeks, I am concerned I was not eating enough of my calories back and sending my body into starvation mode which inhibits fat loss. Could that be possible!

    Thanks so much :)
    You are a twenty year old guy, around 215 pounds. I have no doubt that your heart rate monitor is more accurate than the 236 the elliptical machine gave you.

    Keep up the good work.

    Yes, eat your exercise calories back. However, I would not worry about sending your body into starvation mode.

    At 215 lbs, running for 1 mile burns about 135 calories. So he basically did the equivlent of running 3 miles in 20 minutes which is just over a 6:30 minute mile, a pretty fast pace. An ellipitical is not the same effort as running.
  • rbear713
    rbear713 Posts: 220 Member
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    If you are new to this, and your body is not used to the strenuous exercise, you could easily burn 20 cals/minute. However, as your body adjusts and your fitness level increases, your burn rate will drop!

    If you set your watch up right, chances are its pretty accurate. So keep at it!!

    Also, FO REALZ, this weight loss thing is 90% how much you eat and 10% how much you exercise. Exercise DEFINITELY helps weight loss, but for my money, solid eating habits will get you there faster....

    Dont Worry about Starvation mode - focus on Calories in/calories out...Specifically on Calories IN and how accurately you can track that...

    KEEP Pushin - sounds like you're doin great!!

    *edited to fix stoopid typos! ;)
  • SLLRunner
    SLLRunner Posts: 12,942 Member
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    Hello all,

    So I used my new Polar FT4 hrm at the gym yesterday and the calories burned seemed quite off. For 20 minutes on the elliptical, the hrm told me that I burned about 400 calories, but the machine itself said I burned 236 calories. Which should I go by?

    My second issue: If the hrm is accurate, and I have been using the estimations from the machines for the past few weeks, I am concerned I was not eating enough of my calories back and sending my body into starvation mode which inhibits fat loss. Could that be possible!

    Thanks so much :)
    You are a twenty year old guy, around 215 pounds. I have no doubt that your heart rate monitor is more accurate than the 236 the elliptical machine gave you.

    Keep up the good work.

    Yes, eat your exercise calories back. However, I would not worry about sending your body into starvation mode.

    At 215 lbs, running for 1 mile burns about 135 calories. So he basically did the equivlent of running 3 miles in 20 minutes which is just over a 6:30 minute mile, a pretty fast pace. An ellipitical is not the same effort as running.
    Well, if you don't calibrate your HRM properly, it can be off. However, he is an overweight young person, thus his metabolism is a bit quicker than an older person such as me. I run a 10.1 mile per minute for around 50 minutes and according to my HRM I burn around 425 calories. If I run slower, I burn fewer calories. I know this because I am maintaining my weight in a range and I eat most of my exercise calories back, and sometimes eat a bit over.

    ETA: the machines and MFP always give me WAY higher readings than my HRM.
  • madlerhome
    madlerhome Posts: 7 Member
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    400 calories in 20 minutes is a lot of calories burned, a rate of 1200 calories per hour. I would suggest an incredibly high level of fitness is required to burn at that rate so if you were not entirely exhausted and gasping for air that the 400 is too high. there are a number of websites which provide estimated calories burned for various activities so look for those. Also note that some calorie counters include calories you would have burned even if not exercising while others do not. good luck!
  • SLLRunner
    SLLRunner Posts: 12,942 Member
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    400 calories in 20 minutes is a lot of calories burned, a rate of 1200 calories per hour. I would suggest an incredibly high level of fitness is required to burn at that rate so if you were not entirely exhausted and gasping for air that the 400 is too high. there are a number of websites which provide estimated calories burned for various activities so look for those. Also note that some calorie counters include calories you would have burned even if not exercising while others do not. good luck!
    Yeah, you and the prior poster could be right, now that I think about it. If you HRM is not accurately calibrated, or if the electrodes are not wet enough, they can give strange readings.
  • danielmarksaunders
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    Hmm well I'll try out the hrm again at the gym tomorrow and make sure my info is right and the sensors are wet enough. We'll see what happens!