Is this possible? 240bpm?
 

I received my purchase of a Garmin Edge 305 yesterday. I played around with the HR monitor at home and it showed my hr to be around 55-65bpm while preparing and eating dinner. After dinner, I went out to ride around the block. After coasting down a hill, I noticed the Edge was showing my hr to be around 200bpm. This was pretty much the way it was most of the short ride (on the relatively flat stuff). At one point before a steep climb, the hr wasn't getting picked up for a few seconds. When it came back, I was around 100bpm and it didn't go much higher as I climbed this hill (maybe 8% average). Really, at no point in this short ride did I feel like I was at my limit. Check out the hr data... 240bpm max? Any explanation? Is the Edge not working? Did I do something wrong in using it?

I have been playing with the hr monitor this morning and it seems to be working fine. It is constantly registering around 60bpm while I'm typing away.

What you experienced is interference from power lines. Just ignore the anomalous data.

There are no power lines around that I can see.

Wow! At 240bpm you should be riding into the afterlife.

Reset the Garmin and try riding the same route again and see what happens. It could be some fluke or interference. How was the other data registering (speed, elevation, cadence...)- seem normal?

240 is way, way high. I would also guess interference from somewhere, or a bad contact to your chest.

My usual reaction to a HR of 240 is to go get a crash cart.

It's likely "flapping jersey syndrome". Static electricity confuses the HRM. I see this more in the winter, when it's dry. My HRM will jump from 140 up to 220 in a few seconds. If you see this, try pulling your jersey away for 10 seconds to give the HRM time to update it's averages, and see if it goes back to normal.

Also, I have to put the strap quite high on my chest to make it accurate.

Make sure you wet the contacts when you put the strap on. Sweat is often enough, but sometimes it's a challenge to get a good contact. If a nearby shop has some electrode gel it might be worth a shot too.

I saw readings in the 220-240 range on my Polar when I had a bad contact too, and I started using the electrode gel. It did the trick.

If you go to the Motion Based forum, you'll see a whole thread on this topic. Sometimes it happens b/c of too loose jearsey, bad or dry contact with chest, etc.

Thanks guys for the info. I'll try your suggestions and hopefully get it working.

I now have the Edge as well... haven't noticed it yet... but I did used to have the same issue with my Polar HR monitor. Especially in the winter!

Next time you get an unexpected reading, do a quick check of your pulse (feel for 6 sec X 10) to get an idea of what it really is. That should re assure you. I'm with those have said it's due to some sort of interference. Slobber up the sensor whenn you put it on.

I have the same problem with mine. Its jersey-flap and I've found it is limited to certain fabrics in dry weather. I've owned a couple of HR monitors and the Garmin seems the most susceptible to this of any I've used. I don't think many humans can endure 240 bpm, not for long.

BTW-I think the Garmin tops-out at 240, thats the highest I've recorded.

My POLAR HRM seems to be pretty accurate also, however sometimes I will get some inaccaurate high readings myself. Very rare occurence, matches my OMRON blood pressure meter. Sometimes static electricity from your jersey can affect readings as previously mentioned.

Not sure if it is me, but I do not wet my chest strap elctrodes on either of my straps(2) & can get a reading at the beginning of my ride or as I am typing this response. If I lay down though, then I can not get a reading.

Same thing happened here. It caused a brief moment of panic that probably shot my heart rate to 240 for real. I tugged on my jersey and readjusted the strap and it gradually dropped to a normal reading.

Yup. I've gotten this on every heart rate monitor I've ever had. The Edge 305 seems a little better then others, but not by much. Normally a problem going down hills.

Ive had the same thing happen.. I think its the max limit on the measurable HR and the sensor picked up some weird s**t..

I have measured my heartrate at over 240 bpm. Doctors checked out my heart, one of my valves is weird, and my EKG looks like I'm having a heart attack. My doctor actually told me to carry a reduced size copy of my EKG so I'm not treated for a heart attack if I get knocked out.

However, at 240+ bpm, you know something is wrong. I feel quesy, light headed, have no strength, can barely see, and it's all I can do not to topple over. And that's if I'm just walking around. On the bike I have to stop. It happens spontaneously every now and then. And in a beat or two everything goes back to normal.

If you don't have those symptoms it's some errant signal, whether from your chest band or from something else.

cdr