Wednesday, July 30, 2014

Garmin Troubles

This is a picture of the Modesto Roadmen after a local bike race, ca. 1966. Everyone except for me is holding a trophy. I am holding a repair tag for my bike which broke during the race. Since this post is about my broken Garmin heart rate monitor, I thought this picture was appropriate.

I first started using my Garmin 500 cycle computer with a cadence sensor and heart rate monitor at the end of November of 2012, though I did not post a review of that device until January of 2013. In that initial report, I described a few bugs with the computer but noted that as long as the heart rate monitor kept working, it served its function. By mid-February, after 3 months of use, the heart rate monitor stopped working. As I detailed in a blog post about a month and a half later, I got it working again after a lot of fidgeting. At the time, I believed that what fixed it was to replace the strap that came with the heart rate monitor with a compatible strap from Polar, a belief I maintain until today. At the same time, I bought a cheap, stand-alone heart rate monitor that worked only with its own wrist-watch, as a backup. It is well that I bought the backup, because within four or five months, the new strap also stopped working. As a temporary measure, I switched to the stand-alone. Because I was annoyed at the rapid failure rate of the straps, I was not motivated to buy another one, and so I have continued to use the stand-alone. This cheap heart rate monitor has been working without a single problem for the last fourteen months. In this post, I will explain why this stand-alone, as good as it is, is not an ideal solution, what I am using at the moment, and why I chose what I did. I think the failure rate for heart rate monitor straps I experienced is unacceptable and I hope I have found a solution for it.

All the heart rate monitors with which I am familiar work on the same principle. There is a strap that you wear around your chest which contains electrical sensors. These pick up the signals that control your heart beat from the skin on your chest. This part of the system is entirely passive, it is functionally just a pair of wires (though it is made from rubber and fabric). The signal this strap picks up is transmitted to an active electronic device that is attached to the strap, call it a transmitter. The transmitter can be built into the strap or it can be detachable and it contains a battery. This transmitter sends the heart beat data to a receiver. There are many kinds of receivers, bicycle computers and wrist-watches are the two types with which I am familiar. I have also heard of smart phones being used as receivers. At a minimum, the receiver displays the heart rate data so you can know how hard you are working. In addition, my stand-alone allows you to set upper and lower heart rate limits; the heart rate display flashes when these are exceeded. In addition to these features, my Garmin records the heart rate over the course of my ride for future analysis. Thus, one reason to use a heart rate monitor that works with my Garmin rather than continuing to use the stand-alone is to have these recordings.

Different Straps for Different Apps

I am aware of two kinds of straps for heart rate monitors. There are the expensive "comfortable" ones that are entirely made of a woven fabric, and there are the cheap ones where eight inches of the strap around the transmitter are made out of a stiff, heavy rubber. (This difference is strikingly obvious when you hold them, but I have been utterly unable to find any way of photographing the different straps which makes this difference apparent.) When I got the heart rate monitor for my Garmin back in 2012, I had a choice of either one, and figuring that you get what you pay for, selected the "better" one. The replacement strap I purchased after three months was also of the "better" style, but the stand-alone came with the cheap kind. When I first tried the stand-alone, I did so with some apprehension, but in fact did not find it noticeably less comfortable than the expensive, all fabric kind; the cheap Garmin heart rate monitor thus became an option. So here were my choices in June of last year when my second strap failed (along with their prices):

Stand-alone Polar with wristwatch$60*
Garmin Replacement Strap$33
Polar Replacement Strap$15
Complete Garmin Premium heart rate Monitor (strap & transmitter)$42
Complete Garmin Basic heart rate Monitor (strap & transmitter)$36

* I already had the stand-alone Polar for which I paid $40 back in 2013, but the current price is included here for comparative purposes.

So I ordered another Polar strap. At $15 a strap, I thought it might be worth just replacing the strap as necessary. Unfortunately, Polar had modified its strap design since the first one I bought so that the Garmin transmitter no longer fit. It is a small modification and I wondered if I might be able to grind off some excess rubber and make it work, but this is an idea I have yet to try. The Garmin replacement strap seemed too expensive if I were to be buying three or four a year. So, since I already had the stand-alone, I used that. As it worked for month after month after month, I began wondering about the "Premium" strap; perhaps that's the problem. So a few days ago, I ordered the Garmin Basic heart rate monitor with the heavy rubber segment and built-in (non-removable) transmitter. It works. I now have recordings of my heart rate data so I can, for example, more accurately measure my average heart rate during a 30 minute time trial. (With the stand-alone, I am reduced to glancing at the display now and then and making a mental note that is seems to be holding somewhere between 160 and 165 beats per minute.) How long will it last? As long as the stand-alone? Stay tuned.

1 comment:

  1. At the time, I believed that what fixed it was to replace the strap that came with the heart rate monitor with a compatible strap from Polar, a belief ...