Heart rate strap - Odd readings after an hour

JackPozzi

I've been having problems with my garmin HR strap for a month or so, it's fine for about an hour but then the readings sent to the garmin become very intermittent. For some reason it seems to happen more on uphill sections but then starts working well again on downhills. My initial thought was to change the battery in the strap but that made no difference so I ended up buying a replacement strap but my first ride with the new strap today suffered the same problem.

I'm going to get hold of some of the conductive gel used for ECGs to give that a try but I'm not convinced that will help bearing in mind the fact the the straps work well when I start my rides, I've already worked up a sweat by the time they start malfunctioning but I'm willing to give it a try just so I can rule that out as the cause of the problem.

Anyone got any ideas on potential causes and ideally a cure please?

dabber

I have a similar problem with my Holux HRM. I changed batteries, used gel but no difference. It happened a lot when I was in France with 35+ degree temperatures and the belt was soaked with sweat. Holux have replaced the belt twice under warranty but the problem is still there.

ShutUpLegs

May be you haven't done it up tight enough

JackPozzi

I generally have it tight enough that I can read the opening instructions from the battery cover imprinted on my skin for some time after the strap has been removed!

mikenetic

I don't have to have mine done up nearly that tight to get a nice solid reading. Are you positioning it just below your breastbone?

And, bit of a personal question. Are you more like Tom Jones or Duncan Goodhew in the chest wig department? Not sure if that could interfere with making a good contact.

JackPozzi

It's odd, because I've used a garmin strap for a couple of years and the problem has only started recently, why is why I thought the strap might need replacing. Always put it in the same place, underneath what I claim are pecs.

As for hair, there's a bit there but certainly not in the Tom Jones league, and the area where the electrodes sit are pretty much hair free.

Herbsman

You may be having mini heart attacks due to the intensity of the ride.

JackPozzi

Hum, you've clearly never seen me ride...

mikenetic

Have you tried it with another head unit? The assumption is the band is playing up, could it be the Garmin receiver?

Muffintop

I've been having this on my Garmin 705. It doesn't react to changes as quick as it should though this is the first time I'm noticing it. I usually find a quick under band wipe does the trick after a while.

Wrath Rob

The obvious answer is related to N+1, but is S+1, where S is a sensor e.g. speed, cadence, HR etc. In your case I recommend an immediate upgrade to a power meter of some kind. It won't fix the original problem but will give you something new to worry about instead :twisted:

JackPozzi

Wrath Rob wrote:

The obvious answer is related to N+1, but is S+1, where S is a sensor e.g. speed, cadence, HR etc. In your case I recommend an immediate upgrade to a power meter of some kind. It won't fix the original problem but will give you something new to worry about instead :twisted:

Got 2 of the buggers already, and the new heart rate strap is the cyclops pseudo power thing as well so arguably 2 and a half!

@muffintop - my problems are also with a 705, trouble is at this time of year I'm wearing too many layers to be able to give it a quick wipe.

@mikenetic - That is something I hadn't thought of, I'll try another garmin in my pocket at the weekend and see if both report the same thing in the post ride analysis. I really hope it's not the 705 playing up, I find the mapping on it very useful but don't really like the look of the 800 or 810 which I'd have to replace it with, let alone the prices...

smoggysteve

Are you doing the same route each time? Any power lines at the time you get dodgy info?

Do you take a phone with you? smart phones can interfere with the sensors. I put my cycling computer next to my iphone or pc and it goes mental

JackPozzi

SmoggySteve wrote:

Are you doing the same route each time? Any power lines at the time you get dodgy info?

Do you take a phone with you? smart phones can interfere with the sensors. I put my cycling computer next to my iphone or pc and it goes mental

:idea: You could be on to something there, hadn't even thought about it, but I have recently changed phones. Will try switching it off when I ride at the weekend.

Tend to use variations of about 10 different routes, so don't think that will be the problem, as it happens on Sunday I was out on the MTB with no power lines anywhere nearby.