Heart Rate Monitor Strap and Loose Skin

What do people think of this theory for a problem I have seen twice.
I use a polar H10 chest strap to measure heart rate along with either the Vantage or an older M430 sometimes. The strap can also be picked up by an Precor open stride machine that I use a lot at the gym.
Some months ago the strap started becoming unreliable. You can see this immediately on the Precor machine. The watch takes some time to show a problem. Moving the strap might get it going again but would likely drop out again. I got a new strap and would see the problem with that but then it all went away.
I tried a conductive gel but still saw the problem.
Well I started getting the problem again now. Super infuriating as I live and die by the calorie measurements from this guy.
I realized this problem is cropping up when I am at my leanest. I am probably 100lbs lighter than my highest ever weight. Dieting can cause a thyroid hormone conversion problem that can give you dry skin. I get rashes and an itchy back for example from it. So I thought it might be this but the conductive gel not working suggests this is not the problem. I found bromocriptine gets rid of the dry skin anyway and it will go away when start eating more even without the drug.
I have loose skin on my front that kind of hangs away from my body if I lean forward. So I tried wearing the strap in the wrong place. On the top of my chest. All the problems went away. I get a rock solid receive of the HR on the open stride for well over an hour. Just wearing the strap very tight below my chest did not work so I don't think it's the increased radius. I have the strap on so tight below my chest that it loosens itself during a run so clearly I have it tighter than designed.
My theory though seems kind of crazy. Anyone have similar problems?
Clearly I am going to be sticking with my solution anyway.

Replies

  • Duck_Puddle
    Duck_Puddle Posts: 3,237 Member
    I have very sporadic results with Polar HRM straps. Monday it’ll be fine, Tuesday it’ll tell me my HR is 74 when I’m running and 194 when I’m laying down not moving. Or 0 or 278. Wednesday will be all over the place, Thursday half and half...

    When you say you replaced the strap and would see the problem but then it all went away-what does that mean? What went away?

    If it’s a skin thing. It’s likely the irritation/rash/etc. I have loose skin and haven’t had any issues with
    my HRM straps (except Polar always and others when they need a new battery and/or new strap).

    My guess is it’s just Polar doing what Polar does, but maybe there’s something else happening.

  • NorthCascades
    NorthCascades Posts: 10,968 Member
    Whenever I start getting erratic readings from a chest strap, a battery change makes it good as new again.
  • yirara
    yirara Posts: 9,943 Member
    I have irregular ribs and get odd/unreliable/non-measurements from chest straps. Besides that they are rather uncomfortable on my rib cage.
  • neillc57
    neillc57 Posts: 86 Member
    edited March 2020
    When you say you replaced the strap and would see the problem but then it all went away-what does that mean? What went away?

    I wasn't clear. I am saying when I got heavier I lost the problem. Now I am leaner again I got the problem back.

  • cmriverside
    cmriverside Posts: 34,419 Member
    I'm gonna be super radical here.

    I had a HRM for about a year when I was losing weight and it was helpful at first - but really, after a few months I had good enough data that I really didn't need to use it.

    Maybe you have a lot of past data, too?

    The other thing...have you tried wearing it with the sensor on your back and the elastic at the front?
  • Duck_Puddle
    Duck_Puddle Posts: 3,237 Member
    neillc57 wrote: »
    When you say you replaced the strap and would see the problem but then it all went away-what does that mean? What went away?

    I wasn't clear. I am saying when I got heavier I lost the problem. Now I am leaner again I got the problem back.

    So have you replaced the strap? They have a lifespan that isn’t really all that long.
  • erickirb
    erickirb Posts: 12,294 Member
    I would also point out the HRMs just measure HR, there are calculations that the watch or machines use to try and convert that into cals burned, but it is not exact. You will get a better estimate using "work performed" instead Mets.

    There are calculations out there to estimate cals burned from walking and running that are much much more accurate than an HRM, as an HRM can overestimate a burn if you are sick or tired as your HR will be higher but in reality you would not burn any more cals under those conditions. The calculations uses weight moved over distance, which will give you the same results every time, sick/tired or not. For running: 0.63 x bodyweight (pounds)x miles, walking is similar but believe the multiplier is 0.30 instead of 0.63.

    that said for any machine, other than bike, rower, or treadmill, an HRM will be a better estimate than the machine itself, especially for an elliptical.
  • sdavis484
    sdavis484 Posts: 160 Member
    Whenever I start getting erratic readings from a chest strap, a battery change makes it good as new again.

    Same
  • neillc57
    neillc57 Posts: 86 Member
    edited March 2020
    So have you replaced the strap? They have a lifespan that isn’t really all that long.
    Yes I did. I have also replace batteries. I haven't tried putting the contacts on my back.