HRM shows double cals burned vs MFP & online calorie calcs?

jfrankic
jfrankic Posts: 747 Member
Hello and thanks for reading! I have a basic HRM watch that only calculates calories burned by heart rate based on age and sex, I cannot input weight or height. I do very intense cardio and keep my heart rate at or above 80% for 35 minutes. My hrm says approx 600 calories burned. MFP calculates way less, like 400 or so, can't remember exact. So I found an online calculator that is based on height, weight, age and average hr. This shows about 350. Which should I go by?

This is very important because I am breastfeeding and cannot eat too few calories or my milk supply will be compromised. Wnd of course, I don't want to overeat! Oh, on the elliptical machine, I keep my hr at about 80% and it shows 525 burned in 45 minutes. It basically reads my hr constantly on the handles. MFP shows more for elliptical, less for my cardio. Thanks for any input here!

Replies

  • jfrankic
    jfrankic Posts: 747 Member
    Any expert answers? I guess I just need to know if my HRM watch is accurate even though I can only input age and sex. Thanks!
  • AmyRhubarb
    AmyRhubarb Posts: 6,890 Member
    Is your HRM just a watch or does it have a chest strap as well? The watch-only type are not as accurate as they only go by whatever your heart rate was last time you paused to take a reading. I had one for awhile, finally got a chest strap type and the calorie burn was far lower, but more accurate.

    Since your HRM doesn't have input for your weight, I'd go with MFP I think - it is still an estimate, but has more info about you...
  • LaurenAOK
    LaurenAOK Posts: 2,475 Member
    I'd go with an average of all three numbers, so in your case about 450 calories. Since your HRM doesn't have a place for weight and height it probably isn't 100% accurate, but online calorie calculators aren't 100% accurate either. I'd go with an average for now and maybe save up for a better HRM.
  • dad106
    dad106 Posts: 4,868 Member
    I'd say no.. Your HRM is not accurate. To have an accurate estimation of calories burned you need all personal info, a chest strap and max heart rate..

    I'd try returning the HRM if you can for one that takes all info.
  • jfrankic
    jfrankic Posts: 747 Member
    It is just a watch. I took my heart rate after every few minutes, at least, so it was a pretty accurate reading of my HR throughout the workout. I've had the watch for a while, so I can't take it back. So I'm guessing that an online calc will be more accurate since I can input my height, weight, etc but I still use my watch to get an average heart rate throughout my workout?

    Thanks for the responses!
  • dad106
    dad106 Posts: 4,868 Member
    It is just a watch. I took my heart rate after every few minutes, at least, so it was a pretty accurate reading of my HR throughout the workout. I've had the watch for a while, so I can't take it back. So I'm guessing that an online calc will be more accurate since I can input my height, weight, etc but I still use my watch to get an average heart rate throughout my workout?

    Thanks for the responses!

    No.. Don't use the watch at all. Any reading that you get from that watch(average heart rate, calories burned) will not be accurate.

    The only way to get an accurate heart rate average is to have a chest strap which is continuously monitoring your heart rate. The only way the watch would be accurate is if you kept your finger on the sensor the entire time.. which is pretty much unrealistic.

    Can you buy a new HRM with a chest strap? A Polar FT4 on amazon is around 60 with shipping included.. and it will be a lot better then what you have now.