WARNING! POLAR HEART RATE MONITORS DEFECTIVE!

peterdt

Here’s the scoop. I’ve been using the Polar FT7 since July. During that time I’ve had my weight set at 326 pounds, and have logged 132 hours on my FT7. My average calorie burn per minute was 6.5 calories per minute with an average heart rate of about 109. I thought that was abnormally low considering my weight and was always bothered by it.

Then I bought another Polar FT7 thinking maybe I had a defective one. Guess what? Same results only about 6.5 calories burned per minute.

Then I reset the one of the watches for 190 pounds two weeks ago on a hunch. Logged my results for a week and guess what? My calories burned per minute went to 8.1 per minute with the same 109 heart rate.

In other words my calorie burn went UP from 6.5 calories burned per minute to 8.1 calories per minute at the same heart rate when my weight was reduced on the watch from 326 to 190. This is impossible of course in reality. The watch is not accurate for calories burned at my heart rate.

I did the same experiment with the 2nd watch. Same results. My calorie burn went UP from 6.5 calories burned per minute to 8.1 calories per minute at the same heart rate when my weight was reduced on the watch from 326 to 190 on the 2nd watch as well!

Conclusion: The formulas used to calculate calories for people at higher weights are NOT even close to being accurate.

I would like to ask other Polar heart rate monitors users to do the same experiment. I suspect this problem is widespread. This is a huge product defect and the product should be recalled. Please report back to this post your results of your own “experiment. Also, it may not be for just my model. Please do the experiment for any Polar watch.

mystry11

Buuuuuump

so_losin_it

That's interesting....and crappy! Let us know if you find a brand that is more accurate.

peterdt

let me know what you think if you get a chance to look at it.

peterdt

I will let you know. But I think the problem is at higher weights. At 190 pounds it looks accurate.

iampanda

Wow, that is surprising! I use a New Balance GPS Marathon, and for my weight and age (126 lbs, 26 yrs) it seems fairly accurate.

wackyfunster

The weight probably rolls over at 256 (1 byte).

peterdt

the problem is only at higher weights I think. Would like to get more feedback from others though.

peterdt

huh? is that a joke?

dad106

Before you go claiming that these products are defective, are you wearing them properly? IE, getting the strap wet before using and making sure it's tight enough?

I'm sorry, but at 326 pounds, I highly doubt you can push yourself very hard to get your heart rate up very high without getting out of breath fast... so I can see why it would be lower for someone who is heavier.

Plus calories burned on an HRM have only a fraction to do with weight... the rest comes of from your heart rate, weight, age, etc.

ETA: I see now you said average heart rate... which as I pointed out, for a heavier person could be normal depending on their aerobic fitness.

nashbear

I'm sorry, but at 326 pounds, I highly doubt you can push yourself very hard to get your heart rate up very high without getting out of breath fast... so I can see why it would be lower for someone who is heavier.

He was using the same monitor at whatever weight he is now and doing the same workout with just the settings on the watch different. So the heart rate is the same. the calculation of the calories expended is different.

And people at 326 are perfectly capable of getting their heart rate up.

iWaffle

The weight probably rolls over at 256 (1 byte).

I'd almost accept that as a logical answer. Memory is so cheap I bet they get a normal byte (8 bits) so as long as you weigh under 2,147,483,647 pounds you'll be okay.

Seriously, don't know. Works fine for me at 210.

omma_to_3

Mine seems perfectly logical - the calorie burn has reduced as I've lost weight.

I would suggest contacting Polar directly.

Erienneb

The formula thatt anyone uses for calorie burn gets all wacky the further out of shape you get, this would be true for any HRM brand. The way to be more effective with a HRM is to get your heart rate tested vs your breathing. This way your heart rate is connected to your activity level. My HRM is so much more accurate since I was tested like this vs just using the basic forumla for a woman my weight.

BrianSharpe

Have you contacted Polar's tech support people about this?

Gapwedge01

Mine seems perfectly logical - the calorie burn has reduced as I've lost weight.

I would suggest contacting Polar directly.

The burn goes down as you become more cardio fit not because you have lost weight. Running 3 miles unfit will result in a higher HR average. Running the same 3 miles as a more cardio fit person your burn will go down because you are not pushing your cardio level as you once were. Weight is not involved with that part of it. However, one should change the settings in the HRM when their weight changes.

peterdt

Before you go claiming that these products are defective, are you wearing them properly? IE, getting the strap wet before using and making sure it's tight enough?

I'm sorry, but at 326 pounds, I highly doubt you can push yourself very hard to get your heart rate up very high without getting out of breath fast... so I can see why it would be lower for someone who is heavier.

Plus calories burned on an HRM have only a fraction to do with weight... the rest comes of from your heart rate, weight, age, etc.

ETA: I see now you said average heart rate... which as I pointed out, for a heavier person could be normal depending on their aerobic fitness.

Your response show that you neither thoroughly read my post.

Of course I know the proper use of my HRM. I have had times when it does NOT function properly, but it is quite obvious as the reading become way out of kilter, or don't register at all.

Are you serious? Can't get my heart rate up for a significant amount of time for a person my size. My average workout session is 90 minutes sustained at an average of 109. seems that you no idea what people at that weight are capable of.

this is a link to the algorithm most widely accepted for calorie burn.
http://www.livestrong.com/article/453151-how-to-calculate-amount-of-calories-burned/

Run the numbers and you will see that weight is by far the most important factor in weight loss. Besides all the other variable remained constant in my data. The only thing that varied is the weight. So my results are very reliable.

TKRV

So, at lower weights, is it still accurate or is the claim that this issue affects all people of all sizes who use this product?

iplayoutside19

Have you contacted Polar's tech support people about this?

This^

I've been using a Polar FT7 for 2 years. I've been around 280-300 lbs during that time. The calorie burns seem normal compared the previous HRM's that I've used, and I've had success maintaining/losing my weight when I use those calorie burns along with MFP. (You know, when I actually follow the program) My only agrivation with the FT7 is changing the battery.

And yes, there are people who weigh 300 lbs that can do steady state cardio, not very fast, but it can be done.

peterdt

Mine seems perfectly logical - the calorie burn has reduced as I've lost weight.

I would suggest contacting Polar directly.

The burn goes down as you become more cardio fit not because you have lost weight. Running 3 miles unfit will result in a higher HR average. Running the same 3 miles as a more cardio fit person your burn will go down because you are not pushing your cardio level as you once were. Weight is not involved with that part of it. However, one should change the settings in the HRM when their weight changes.

Point taken. But calories burned has everything to do with heart rate? this is widely accepted. When you get more fit your heart rate gets slower and thus you burn less calories if all other variables are the same.

You do understand that right?

omma_to_3

Mine seems perfectly logical - the calorie burn has reduced as I've lost weight.

I would suggest contacting Polar directly.

The burn goes down as you become more cardio fit not because you have lost weight. Running 3 miles unfit will result in a higher HR average. Running the same 3 miles as a more cardio fit person your burn will go down because you are not pushing your cardio level as you once were. Weight is not involved with that part of it. However, one should change the settings in the HRM when their weight changes.

Weight absolutely is involved in the equation. It went down for BOTH reasons. My average HR has gone down, but not as significantly as my weight. I change my HRM settings every 10 pounds. I actually set it for 10 lbs. less than I really weigh, and then once I reach that weight, put it down 10 more lbs.

peterdt

So, at lower weights, is it still accurate or is the claim that this issue affects all people of all sizes who use this product?

it seems to me that the lower weights are accurate. when I entered the data for 190 those numbers sounded right compared to online calculators and accepted algorithms for calculating this.

Weezoh

Just for the heck of it I looked for a workout session where I averaged 109 on my FT7 and found one. When I looked at the calories per minute it was 7.5 currently i weigh 255 so seems to be roughly in line with your 190 and 320 weights. I'm assuming that the hrm is set with a particular sweet spot and as you depart from that sweet spot going in either direction the accuracy is going to suffer. What that sweet spot is I don't know.

peterdt

Have you contacted Polar's tech support people about this?

This^

I've been using a Polar FT7 for 2 years. I've been around 280-300 lbs during that time. The calorie burns seem normal compared the previous HRM's that I've used, and I've had success maintaining/losing my weight when I use those calorie burns along with MFP. (You know, when I actually follow the program) My only agrivation with the FT7 is changing the battery.

And yes, there are people who weigh 300 lbs that can do steady state cardio, not very fast, but it can be done.

Please share some data? "seems normal" does not really help much in getting to the bottom of this issue.

I have emailed Polar, no reply yet.

Gapwedge01

Mine seems perfectly logical - the calorie burn has reduced as I've lost weight.

I would suggest contacting Polar directly.

The burn goes down as you become more cardio fit not because you have lost weight. Running 3 miles unfit will result in a higher HR average. Running the same 3 miles as a more cardio fit person your burn will go down because you are not pushing your cardio level as you once were. Weight is not involved with that part of it. However, one should change the settings in the HRM when their weight changes.

Weight absolutely is involved in the equation. It went down for BOTH reasons. My average HR has gone down, but not as significantly as my weight. I change my HRM settings every 10 pounds. I actually set it for 10 lbs. less than I really weigh, and then once I reach that weight, put it down 10 more lbs.

I never said weight was not part of the equation. It surely is. And yes you adjust your settings accordingly to your weight. My point was for the same duration and same steady state exercise like running as you become more cardio fit the HR average goes down. Don't get so defensive.

DanaDark

Point taken. But calories burned has everything to do with heart rate? this is widely accepted. When you get more fit your heart rate gets slower and thus you burn less calories if all other variables are the same.

You do understand that right?

Calories burned does not have everything to do with heart rate, and it is not widely accepted. Calories burned has to do with VO2max, which heart rate is a good indicator for, but not an absolute determination for. If calories burned has everything to do with heart rate, we could all drop the gym, and go to the movies to watch suspense and horror movies.

omma_to_3

I've got nothing to get defensive about, but you clearly stated "The burn goes down as you become more cardio fit not because you have lost weight." I didn't want people to think that weight going down doesn't reduce your burn.

peterdt

Just for the heck of it I looked for a workout session where I averaged 109 on my FT7 and found one. When I looked at the calories per minute it was 7.5 currently i weigh 255 so seems to be roughly in line with your 190 and 320 weights. I'm assuming that the hrm is set with a particular sweet spot and as you depart from that sweet spot going in either direction the accuracy is going to suffer. What that sweet spot is I don't know.

I don't agree. compare these numbers. Does this look right to you? your age also is different than mine I guess so that could affect it, but weight is has much more "weight" in the algorithm overall. your burn is likely significantly higher than what your FT7 is saying.

check out this site and plug in your numbers here.
http://www.calories-calculator.net/Calories_Burned_By_Heart_Rate.html

8.1 calories/minute - 190 pounds.

7.5 calories/minute - 255 pounds (your numbers).

6.5 calories/minute - 326 pounds.

DanaDark

To do a proper experiment, you need:

A person at 190 pounds and a person at 326 pounds where both people have the same V02max. From there, you'd also need to use the same monitor and ensure the heart rate stayed the same between the two participants.

Simply telling the monitor you are 190 is not sufficient.

iplayoutside19

Have you contacted Polar's tech support people about this?

This^

I've been using a Polar FT7 for 2 years. I've been around 280-300 lbs during that time. The calorie burns seem normal compared the previous HRM's that I've used, and I've had success maintaining/losing my weight when I use those calorie burns along with MFP. (You know, when I actually follow the program) My only agrivation with the FT7 is changing the battery.

And yes, there are people who weigh 300 lbs that can do steady state cardio, not very fast, but it can be done.

Please share some data? "seems normal" does not really help much in getting to the bottom of this issue.

I have emailed Polar, no reply yet.

I don't have my HRM with me. I'll have to look at it later tonight, but I will reply. I will say avg of 109 seems kind of low. What kind of activities are you using it for. 109 is what my avg HR is when I'm on a hike or walk. I usually only wear mine when I've going to run or bike and my HR would at least be in the 130's.

As to the other argument. Calories are a unit of energy. A major part of any energy consumed equation is mass. V02 Max plays a small part but weight & speed are the two main factors.

Gapwedge01

I've got nothing to get defensive about, but you clearly stated "The burn goes down as you become more cardio fit not because you have lost weight." I didn't want people to think that weight going down doesn't reduce your burn.

Point made.