MHR224

So I only have this jersey and the main fabric is made out of polyester. I've noticed that it significantly affects my heart rate when I know it's significantly lower than the reading on my garmin. I've had reads of my heart reaching almost 230bpm and I know that ain't right. Any insight on what kind of jersey to wear during races that won't affect my HRM?

iNewton

Could it perhaps be a malfunctioning belt unit? I'd check with Garmin first to rule that out.

MHR224

No it's not the garmin. I ride with another skin tight polyester shirt from walmart with a riding jacket over it in the cold and it has no affect on it. What I'm thinking is that the wind hits the jersey then hits the monitor creating anomalies? If so what kind of jersey should I use or is it just a manufacturing flaw with garmins HRM's?

merlinextraligh

I seriously doubt the material of the jersey is affecting this. The fact that the other is "skin tight" may be affecting how well the strap is making contact.

rm -rf

It's static from the cloth. I don't use my HRM in the winter because my base layers do the same thing. I can make it jump into the 200s from 140 just by flapping the loose layers by hand.

I tried static sprays, but it didn't fix it. Taping a piece of paper towel (for insulation) on top of the strap does help, but it doesn't stay in place.

DXchulo

I've had loose jerseys cause a problem when they're flapping in the wind. Are you sure it's not the jacket?

Or perhaps one shirt shields the jacket from the flapping better than another shirt?

jeffc7

I think it has more to do with a looser fitting jersey. I have the same problem with my Garmin. Sometimes in the beginning of the ride (1st 2-3 miles) my heart rate is at 230-240. I'm pretty sure I would be dead. Then it settles in and gos back to normal. My tighter, euro fit, jerseys do not seem to have this problem. I also adjusted the HR strap several times and the same thing happens over and over. The manual says to also try and turn the HR sensor around so that it is on your back. I have not tried this, but its worth a shot.

spdrcr5

I've never had an issue with jerseys or shirts that I've worn over my HRM strap. Do you wet the sensors before putting on the HRM strap to insure proper contact? Because the skin tight suit doesn't cause an issue it could be poor strap to skin contact. How loose/tight is the strap? Do you have this issue when riding without a shirt/jersey?

urbanknight

I have had a jersey that flapped around in the wind just right so that it struck my heartrate monitor strap. It's hard to catch since it only happens when you're in a specific position, but once I stopped wearing that exact jersey, I had no problems. Other loose jerseys were fine, this one just seemed to be cut perfectly to make it flap against my chest.

cbaronzzi

This is a very comforting thread for me. I just started using a heart rate monitor about a year and a half ago. On several cool spring rides last year I noticed that my heart rate monitor would register about 260 bpm early in the ride. Although I didn't feel like my heart was racing and didn't feel any pain/discomfort, it concerned me. I have been wondering ever since if I am going to drop off my bike dead one day. But, if it is true that a flapping jersey and/or static buildup can affect your HRM, that is a perfect explanation. I only noticed this problem on cool days and before I started sweating. Also, I live at the top of a hill so the first mile of my ride is a 30 mph downhill. Maybe I am not gonna drop dead! FYI my HRM is a Polar RS200 (I know, its a "running" HRM but it does the trick)

aham23

yep it is the flapping jersey syndrome. there have been a few post over at Motionbased.com on the same issue. i even had it happen to me on a 40 mph decent where my HR hit 226 bpm!!! later.

Carbonfiberboy 

Wow, FJS! I also noticed this and that it only happened early in the ride before I started sweating, or sometimes after a long descent. I'm a transmitter licker, too. Presumably sweating obviates FJS, as it eliminates the static.

'nother

FJS is pretty common. If you are handy with a sewing machine and/or know someone who is, it might be possible to take in some of the extra material and tighten up the fit a bit. Or just eat a lot of donuts and fill that sucker out

VegaVixen

Check the Garmin user manual Appendix under "Pairing Tips, Heart Rate Monitor Only."

You could wear a very tight jersey to avoid the rubbing that induces static charge. Or put adhesive-backed velcro on the shirt side of the monitor, and sew velcro onto a double layer of old T-shirt, creating a cotton buffer.

tbdean

I'm on my third HR monitor (love gadgets...) and they've all done this to me. It just started up again now that it's warmer and my jersey is flapping again.

Hmm, interesting. Has anyone tried this? It makes sense.

whiterock

I've had the same issue with my Garmin HRM....I just splash some water on the jersey over the monitor before I start to keep the static charge from building up. Later after I'm sweating, it isn't a problem.

luv2climb

Same problem happens here too. I have noticed one other factor, humidity. When the humidity starts dropping in the low 30%'s it really becomes a problem. When the humidity is in the 40% or higher I never have a problem. We had about one week in January here in Nor California where we were in the mid 20%, HR readings went crazy that week!

I use Babump and it helps a little but not much. I also tried putting electrical tape on the backside the strap, did not help much.

Best solution is as had been mentioned, nice tight fitting jerseys!

I have the Edge 305 now but have also had this problem with the Polar's.

patentcad

NJ gets blamed for everything.

NJWheelBuilder

Are you guys sure it's the jersey? I always use my Polar S625X and I have never had a problem that even seemed related to clothing. Typically, the really high numbers are caused by some other interference like proximity to high voltage electric lines. A jersey causing an issue seems pretty far fetched to me.

MHR224

Well I train on my indoor trainer with the same jersey that I have trouble with outdoors and the HRM seems to work perfectly indoors with it.

VegaVixen

Do you sweat more indoors? Or perhaps the jersey doesn't rub against the monitor as much?

luv2climb

Heres the way I look at it (I am not scientist but I am sure there are some here that can help):

Ever pulled some clothes out of the dryer and they were full of static cling. All that tumbling and rubbing in the dryer build up static electricity.

Now think about a loose fitting jersey flapping around in the breeze. Same rubbing effect can happen. How does your HRM strap monitor heart rate, electric pulses. That static electricity interfers with it measurements.

My twisted logic at least. Now lets see if someone can back me up.

DocRay

FJS affects 1 in 100...stop the silence, give today so that FJS sufferers can receive proper fitting jerseys.
only you can help us find a cure.

The FJS Foundation of America.

garysol1 

did a little experiment today. I was wearing my team jersey that feels like it is a poly/lycra mix of some sort. Earlier in the season when I had been wearing a baselayer under my jersey my HRM on my 305 worked perfect. Now that it is warmer and I am only wearing the jersey top my readings have been crazy. So today while warming up my HRM reading was at 220. I gently pulled my jersey out and away from the HR strap. Slowly my HR dropped down to the 130's. As soon as I let my jersey go my HR steadily climbed back up to the 220's. After about 10 miles everything seems to calm down and my readings appear normal. I am thinking that once the jersey gets a little damp with sweat it no longer makes static electricity. I wonder if I spray the front of the jersey with a static guard if that would help....

luv2climb

Update us after your experiment. I did not think of static guard. If I have some at home I will try it too.