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Heart Rate Monitor Help :-)

steffi29986 Posts: 41 Member
Hi everyone,

Hoping someone can help me, I recently bought the Polar FT7 and really liking it so far. The only issue I have is with this fat burn/ fitness zone thing, is it important for you to stay within the fat burn zone if thats what you are trying to do? So for example I went out for a power walk this evening just before my dinner for 35 minutes. It says I did 13 minutes in fat burn and the rest in fitness. I can only imagine that I would have to walk really slowly to stay within this zone. I'm just confused, any help would be really appreciated.

Thank you for any advice in advance :-)


  • bwogilvie
    bwogilvie Posts: 2,130 Member
    The "fat burn" zone is meaningless. As Dr. Tim Noakes points out in his book The Lore of Running, even if you burn a higher percentage of calories from fat when exercising at low intensity, you will burn more fat calories total at a higher intensity.

    Moreover, as long as you are consistently maintaining a calorie deficit, you will lose weight. That lost weight will come from one of two places: (1) fat tissue and (2) lean body mass - mostly muscle.

    It's a good idea to do some strength exercises while losing weight to ensure that most of your loss comes from #1, not #2. As long as you do that, it doesn't matter whether the calories you burn while exercising come from fat or carbohydrates, because you'll adapt to use more fat during everyday activity. Almost all of my cardio is at moderate to high intensity, about 7-10 hours a week now that the summer is here, and I've lost quite a lot of fat.

    It's also worth remembering that most HRMs are best at estimating energy expenditure for steady-state cardio, such as brisk walking, running, cycling, etc. at a near-constant effort. The more you vary your effort, the less accurate their calorie estimates become.
  • steffi29986
    steffi29986 Posts: 41 Member
    Thank you for that :-)
  • TAsunder
    TAsunder Posts: 423 Member
    I spend about zero percent of my time in the fat burn zone. I like to go right to max, apparently.
  • MollyNK88
    MollyNK88 Posts: 54 Member
    I have the same HRM as you and I never look at the fat burn zone. I just keep an eye on my heart rate and my calories burned. I love it for more accurate tracking!