Heart Rate Zones question

3foldchord

BACKGROUND INFO: I just got a Fitbit Charge HR. I had used a chart to find the heart rate zones for my age and Fitbit seems to use the same zones. I think they may be off for me. My heart rate gets kinda fast easily. My age is 44F. My resting (sleeping, when I wake) is about 60. My "sitting in the couch reading" is about 75. My "two minutes going super slow on the elliptical machine" is 155. Anything over that makes me dizzy and see spots...... anyway, according to the charts and Fitbit, my Fat burning zone is between 88-130(ish). I get to 110 just walking to the mail box. I'm sure I can't be in the fat burning zone just getting the mail or making dinner.

QUESTIONS

If my heart is used to being in the Fat Burning Zone on a regular basis, am I correct to assume I'm not really burning fat in the zone for "5.3 hours " during the day as my HR monitor says?

Should I change Fitbit settings so it doesn't start my fat burning zone until around 115?

Any suggestion how to find a more accurate FB zone for myself? Does it really matter?

3foldchord

Just did more research . Apparently Fat Burning Zone for heart rate is kind of a myth, not really a big deal where in what zone I am. So, I will just stick to my original plan for HR monitor. .. keep my heart rate from getting too high (as it has a tendency to do then I get dizzy and see spots, etc)

rileysowner

I was going to say that the fat burning zone while not a myth is a big misrepresentation of what the fat burning zone really does. Have you talked to your doctor about the dizziness and spots when you exert yourself? If you have not, you really should as it could be a serious medical issue you need to address.

3foldchord

You are correct.. "misrepresentation " is a better word. And yes, I have talked to my doctor and had some tests, in short: he says to pay attention and know myself... which is what the HR monitor is for, so I can pay attention and slowdown before it gets too high.

rileysowner

3foldchord wrote: »

You are correct.. "misrepresentation " is a better word. And yes, I have talked to my doctor and had some tests, in short: he says to pay attention and know myself... which is what the HR monitor is for, so I can pay attention and slowdown before it gets too high.

Good to hear. I know enough people who have had issues that were similar and tried to self diagnose and struggled needlessly with something manageable. Glad to hear you had it checked out.

BrianSharpe

At the risk off getting a little off topic......would I be correct in assuming that you've been cleared medically to exercise? The getting dizzying and seeing spots is a little worrisome......

NorthCascades

A few thoughts.

(1) Your Fitbit and the chart put your zones in the same place, because they're both making the same assumption about what your maximum heart rate is. Honestly Fitbit's programmers probably used the same chart. I'm guessing it's 220 minus your age. Somebody came up with that formula (and different people came up with others) based on fitting a formula to a bunch of data. It's not going to be terribly accurate for an individual. And if it's wrong for you (which it sounds like), then all your zones will be wrong too.

(2) The way Fitbit's HRM works isn't the most accurate in the world. It's not that Fitbit is bad, they just went for comfort and convenience and 24/7 monitoring. Also, accuracy is going to depend on a lot of things like where and how tightly you wear it, and other factors. If in doubt, see if you can test it against a borrowed chest strap, an app that uses your phone's camera, or even taking your pulse manually.

(3) You asked how you might figure out where your fat burning zone is with better accuracy. A lot of people think basing your zones on your heart rate reserve (max - resting hr) instead of max heart rate does exactly what you want.

(4) Have you done a lot of exercise before? Some of what you describe (heart rate elevating quickly, feeling dizzy at high exertion) sounds like what happens when people first start to exercise before their body adapts. But your resting heart rate is very low which is typical of somebody who's been doing a lot of cardio for years.

3foldchord

NorthCascades wrote: »

A few thoughts.

(1) Your Fitbit and the chart put your zones in the same place, because they're both making the same assumption about what your maximum heart rate is. Honestly Fitbit's programmers probably used the same chart. I'm guessing it's 220 minus your age. Somebody came up with that formula (and different people came up with others) based on fitting a formula to a bunch of data. It's not going to be terribly accurate for an individual. And if it's wrong for you (which it sounds like), then all your zones will be wrong too.

that's what I figured, something like that.

(2) The way Fitbit's HRM works isn't the most accurate in the world. It's not that Fitbit is bad, they just went for comfort and convenience and 24/7 monitoring. Also, accuracy is going to depend on a lot of things like where and how tightly you wear it, and other factors. If in doubt, see if you can test it against a borrowed chest strap, an app that uses your phone's camera, or even taking your pulse manually.

(3) You asked how you might figure out where your fat burning zone is with better accuracy. A lot of people think basing your zones on your heart rate reserve (max - resting hr) instead of max heart rate does exactly what you want.

thanks, I'll look into that.

(4) Have you done a lot of exercise before? Some of what you describe (heart rate elevating quickly, feeling dizzy at high exertion) sounds like what happens when people first start to exercise before their body adapts. But your resting heart rate is very low which is typical of somebody who's been doing a lot of cardio for years.

that's what my cardiology said (he said it looks like I have the heart of an old man who's never exercised once I hit the treadmill, but it looked like healthy BPM off the treadmill) I have always been "passively active" , casual bike rides, hikes, light exercise.... and been actively exercising and lifting weights for 3 years. About 20 yrs ago I was DXed with a mild tachycardia condition, was told I could do what I felt comfortable doing and could self manage.(&had that re-evaluated 5 yrs ago with a new doctor) But I think I can improve on what I do if I track my HR and can keep it from going to high while working out then I can workout a bit more, which will strengthen my heart in the long run.

_Waffle_

BrianSharpe wrote: »

At the risk off getting a little off topic......would I be correct in assuming that you've been cleared medically to exercise? The getting dizzying and seeing spots is a little worrisome......

Right? My lungs and heart just beg for relief. I can keep my max HR up till I lose the mental struggle to maintain that level but never dizzy and there are no spots.

3foldchord

_Waffle_ wrote: »

BrianSharpe wrote: »

At the risk off getting a little off topic......would I be correct in assuming that you've been cleared medically to exercise? The getting dizzying and seeing spots is a little worrisome......

Right? My lungs and heart just beg for relief. I can keep my max HR up till I lose the mental struggle to maintain that level but never dizzy and there are no spots.

I've mentioned more than once that I have. Although, I realize not in my original post.

awinner_au

3foldchord wrote: »

I've mentioned more than once that I have. Although, I realize not in my original post.

I suppose its the dizzyness and spots thats making people comment, I do HIIT and hit max HR (184) regularly with no side effects.

Im sure you have already come across enough material busting the fat burning zone myth. Here is a nice article http://www.builtlean.com/2013/04/01/fat-burning-zone-myth/