Training & Nutrition - Heart Rate Monitor Issues

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Magnolia_Fan
01-06-06, 09:49 PM
I just recently got a Timex HRM, and i'm having an issue with it. It works fine when I'm sweating quite a bit, but when I decend or am not exerting myself too much it gives me wacky data, like 240 beats per minute. I've drenched the sensors with water and tightened the straps. Any tips to making it work all the time? I've heard there are gels you can use...


supcom
01-06-06, 09:58 PM
Once you begin sweating, there should be plenty of conductivity between you and the strap regardless of whether you are climbing or descending.

An abnormally high reading is a sign of interference. If you have a wireless speedometer, try leaving it home next time and see if the problem clears up.

BTW, I find it helpful to use a pinch of salt with a few drops of water when first putting on the strap. Plain water is not conductive.

WarrenG
01-06-06, 10:24 PM
A bit of spit on the contacts has always worked well for me. One of the gels is called "Ba-bump", as in, the sound your heart makes.

The reading of 240 is probably the maximum of that HRM. Since you mention it happens while descending it's possible that the strap isn't tight enough and is flapping a bit when your jersey is doing the same while going fast.

-Warren


lillypad
01-07-06, 06:07 AM
K-Y jelly, which you can pick up virtually anywhere, is more or less water fortified with sodium hydroxide. This works well until you begin to sweat and you body releases its own sodium which acts as the electrical conductor for the HRM.

tippy
01-07-06, 07:26 AM
I reread the instruction on my Forerunner 301 HRM. I found it funny that Garmin's instructions recommended cotton clothing and not synthetic over the HRM. Apparently they found that synthetic jerseys (about 99% of all cycling jerseys) cause noise on the HRM if the material is allowed to flap around or against the HRM sensor. Go figure.

Good Luck,
d.tipton

Trekke
01-07-06, 07:36 AM
I but when I decend ...
Common problem on decents - your just outrunning the signal. ;)

Polonswim
01-08-06, 10:17 PM
...Garmin's instructions recommended cotton clothing and not synthetic over the HRM. Apparently they found that synthetic jerseys (about 99% of all cycling jerseys) cause noise on the HRM if the material is allowed to flap around or against the HRM sensor.

I think it has to do with the beating of the material against the sensor creating a small electrical charge that the sensor reads. I have the same problem on descents. It scared the hell out of me the first time I turned off of my street and started going down hill, looked at my HRM and saw a reading of 255. I thought my heart was going to explode or something. Since then, I have learned to use the first part of my ride as a warm-up BEFORE turning on the HRM.

I am wondering if there something to put over the sensor to prevent the false reading. Maybe athletic tape or something.

Guest
01-09-06, 05:16 AM
I have this problem with my Timex HRMs. I called Timex- they said when you get the screwy readings, it probably is because the strap is not tight enough.

*sigh* I've had such problems with my Timex HRMs. I regret buying so many of them to train my clients.

Koffee

StanSeven
01-09-06, 05:23 AM
I also had the same problem with my Timex. They told me the transmitter/strap was faulty and promtly replaced it. I still don't get readings until I am really sweaty.

I have two types of problems. The first is getting it to start reading at all in this cold weather. The other is maintaining the reading once it starts and after I get the swaet going. Often it hits the 240 peak like you indicated which means I lost connectivity. I have to stop and readjust the strap. By then I lost all the data like average heart rate and the time in each zone.

Timex just don't work.

NoRacer
01-09-06, 06:34 AM
I have the Timex HRM and the Bodylink. I always wet the straps before use and sometimes use the table salt trick to increase conductivity. But, when the humidity level is low and it's hard to keep the moisture between your skin and the HRM contacts you need something persistent, like a gel--like Ba-Bump or Axiom H.S.E. (or spit).

StanSeven
01-09-06, 06:55 AM
Yeah, but something isn't right with Timex units. I had an Oregon Scientific HRM for years. The only time I even had problems with occassional interference from the huge power lines or the airport. Even when my Timex is reading, it ofetn stops when I go downhill fast. I can't figure that out except maybe moisture gets wicked aawy.