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Discussion Starter · #1 ·
I've had my HR monitor give some extremely wild readings on a couple of occasions. I had it happen yesterday. On a mtn bike ride that lasted about 45 min w/ a whopping 140ft of ascent, my monitor showed an unbelievable max HR of 216 (I wish I could attain a max of 200+bpm), with an average of 151. Now when I downloaded the data to my computer I got different figures. My max was now showing as a more believable 180-something.

Anyone have any ideas why the monitor initially shows such a crazy figure, but when downloaded to the computer it corrects the reading/s.
 

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Hey don't worry about it, this morning when out on a local ride my Garmin Edge 305 showed an indicated 599MPH (I think at the point where it lost satellite reception!), I knew I am getting faster but still!!! :eek:

:eek:
 

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could be...

I've had similar wild readings on my polar and others I know who ride in same areas have the same issues. As the HR Monitor is basically measuring electric pulses any source of strong electomagnetic energy may cause these issues. Could be high power wires, telecomm equipment, aliens... :rolleyes:

As far as the different data present when you downloaded the data I wonder if the software is smart enough to discard any wildly crazy numbers. In statistics I remember this is sometimes done to eliminate data that is likely not relevant. Could be the software ignores any readings above your set max HR?
 

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The manual says becareful if riding near power lines, it can accidentally read them and give crazy readings. I personally have gotten some crazy readings passing certain places - 55mph on flat barely chugging along :eekster: I have also seen the same 215 on several occasions and once it was there for 1 solid minute so I'm not too sure if that's accurate or what.

As to why the actual HRM shows the high readings and then the software gives more realistic readings.... it's because the software has a "check" for setting it to "correct" readings automatically when it DL's it to your comp. You can turn this feature off if you wish and then do it in the software after yo've looked at the graph etc. - it's in there somewhere can't find it right now, but it's called ERROR CORRECTION.
 

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DirtSnake said:
I've had wild readings occasionally - I finally figured out it was from my jersey zipper flapping in the wind - creates some electrical current that fools the HRM
This is almost always the trouble for me. I've even isolated it to my 2002 Castelli team jerseys. This is even worse when the humidity drops. Fabrick softener can help a little but dowsing your jersey with water works best. It really can be frustrating!
 

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Discussion Starter · #7 ·
LyNx said:
The manual says becareful if riding near power lines, it can accidentally read them and give crazy readings. I personally have gotten some crazy readings passing certain places - 55mph on flat barely chugging along :eekster: I have also seen the same 215 on several occasions and once it was there for 1 solid minute so I'm not too sure if that's accurate or what.
That makes as much sense as anything. While I don't typically ride near any major powerlines, the bulk of my riding takes place on military property where phone/tv/radio interference is almost the norm...so maybe that's the culprit.

As to why the actual HRM shows the high readings and then the software gives more realistic readings.... it's because the software has a "check" for setting it to "correct" readings automatically when it DL's it to your comp. You can turn this feature off if you wish and then do it in the software after yo've looked at the graph etc. - it's in there somewhere can't find it right now, but it's called ERROR CORRECTION.
I didn't know that. I'll have to check that when I get a chance.:thumbsup:
 

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Well anything like that that will put out a strong electrical type signal - radios and such are very guilty culprits of this.
SeanL said:
That makes as much sense as anything. While I don't typically ride near any major powerlines, the bulk of my riding takes place on military property where phone/tv/radio interference is almost the norm...so maybe that's the culprit.:
 

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DirtSnake said:
I've had wild readings occasionally - I finally figured out it was from my jersey zipper flapping in the wind - creates some electrical current that fools the HRM
I've got this problem with the numbers getting high, because of strong headwind, but couldn't understand why. Metal zipper - that makes sense. :thumbsup:
 

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I have seen weird numbers (220) on my 725i too. Whenever you see those numbers again; look around. I always see a power line near by. The power line is probably running 220 volts; hence the reading of 220 on the polar.
 

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rickm said:
I have seen weird numbers (220) on my 725i too. Whenever you see those numbers again; look around. I always see a power line near by. The power line is probably running 220 volts; hence the reading of 220 on the polar.
interesting. our powerlines must run at 235 volts because that seems to be the most common reading i get when there is interference.

rt
 

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The 220 and 235 numbers are probably just as high as the monitor can go.
The typical high voltage wires run 9600 or 19200 volts (I believe....I'm not an electrician).
I can get zero readings and 220 readings when I pass through microwave repeater areas as well as high voltage wires.
The readings that are the worst are the 165s when you know/feel that you are at 155.
That really throws you off. I have to get my pulse on my neck to double-check the monitor. Oh well, they are just a tool, not perfect.
 

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I had the same issue - intermittent high readings that I couldn't attribute to anything around me (would not always happen in the same area, no powerlines around, etc.).

I discovered that if I pressed the transmitter against my chest w/my hand the readings would descend to a normal reading & then go back up when I released pressure.
I'm embarrassed to say this in "public" but I found that "trimming" (okay, okay, shaving) my chest hair stopped the problem. It's been a month or two & I've noticed the problem has returned along with the regrowth of my chest hair.
I suspect that, in my case anyway, just keeping the hair about 1/2 the normal length would work fine & not leave me looking so metrosexual...
 

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Thanks for that superb piece of advice we didn't already know :skep:
doctorbangbang said:
Make sure you moisten your chest strap, lick it or drop a bit of water on it before you put it on. My Polar tells me my heart rate is 0 (i'm dead) or over 200 (I'm gonna die!) if I don't do this! Simple solution....
 

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Answers

I ride where there's no electrical interference. The Polar can give high readings at the start when (1) there's not enough water/sweat on the strap and (2) a high speed tucked descent sends a wind down my chest. (No zipper either)

It's just a matter of intermittent contact.

The Polar records data at intervals of 5, 15, or 60 seconds. The HR recorded is the average over that interval. So you could have an instantaneous maximum reading higher than any recorded average number. The maximum is stored separate from the recorded series.
 
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