225bpm hr spike during ramp test

Bit of history…at 50 years old, I’ve been cyljng for nearly 2 years now, and have been properly training for the last year with my first road bike purchased this time last year. I bought a cheap Coospo heart rate monitor on Jan of this year to aid my training, and my max heart rate has slowly risen from 172 initially to 177.

I’ve done a couple of 20 min ftp tests and it never went over 177.
Now When I did my first ramp test, my heart rate went up slowly and steadily as normal, but when things got really tough I saw a quick spike up to 205 bpm. Scared the hell out of me so I stopped with an ftp of 279.
I thought it might be a faulty strap so I bought a new one. But on a particularly hard ride, my heart rate rose again steadily and stayed near max (175) for 5 mins, then spiked to over 200.

I nervously did my second ramp test today after 6 weeks of SS HVB1, expecting another spike…and it did it again. Same pattern…slow steady rise, a min or so at max, then a quick rise to 220bpm. :open_mouth:. I stopped the test early, I could have gone on for another minute but that spike was terrifying. I didn’t feel any different, no dizziness, no thumping in my chest.

I’m thinking it may be the cheap monitor just giving up and getting confused at high heart rates. So I’m going to splash out on a Polar h10 with ecg. If it does it again after this then I’ll know it’s my heart. I thought it might me afib but I don’t have any racing normally. And my resting hr is around 45.

Has anyone else experienced anything like this?

You mention a strap…
so guessing this is a chest strap?

My Tickr started to spike randomly like that during indoor session. I got a Polar in the end as well and it has been perfect every ride since. Only other time I’ve seen this was a regular thing when I wore merino fabric jerseys with no base layer - that would give crazy numbers in warm weather for some reason. Adding a synthetic baselayer cured all those issues. When indoors I do make sure the strap sensor is moistened before I put it on.

Yes it’s a chest strap monitor.

That’s the thing, they aren’t actually random spikes. They happen after sitting at my max HR for more than a couple of minutes. It rises quickly then goes down to normal just as quick.

How did you actually feel during the test? Did your HR actually go that high and youd definitely feel it if it did. I have had my HR strap (a Garmin HR Tri) show that I have a HR of somewhere in the 250s… while the strap is sat on a table when I have taken it off following a run. I definitely wouldnt discount the strap giving up the ghost. But if you did genuinely feel like your HR did spike up then go to your doctor.

Other than the strap reading…
Did you felt your HR racing?

My max HR running is about 200… I usually get to 195 on 5K races for like 5 minutes at the end when I am pushing as hard as i can possible can… Ive got to 205 going HARD uphill…and I am telling you man… you would know the difference between 177 and 205…
You would probably be close to fainting… light headed… and tingling fingers and toes…
its a feeling you would never forget!

I felt as terrible as I normally do on max efforts lol. But it didn’t feel like it was going that fast. No dizziness etc.

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No, didn’t feel any of that. Just the normal drowning feeling when at max intensity lol. No dizziness, no tingling. Dropped really fast when I stopped too.

Just about to pick up a Polar h10. Hopefully that’ll tell me if I’ve got some kind of abnormal rhythm going on, and/or if it was just down to a faulty monitor.

But that’s the thing…it’s very steady until it gets up to and stays at max for a minute or so.

I suggest two things:

  1. Given this has happened more than once, then just as a sensible precaution go and get yourself checked out by a qualified physician. It won’t hurt, will be fairly easy to arrange and will provide piece of mind at the very least

  2. Find / borrow / buy a complete replacement HRM as opposed to a new strap; to cross-test your hypothesis that it’s the monitor playing up. This will be a (reasonably) definitive test since if there is no repeat when using a different piece of kit then it can be attributed to an equipment issue.



Good plan. I’m actually buying a new Polar h10 with ECG tonight. So I’ll redo the ramp test with the new monitor, and if it happens again then I’ll get myself checked out.

Next time that happens, measure your HR the old fashioned way, with your fingers on your wrist. (Or get someone else to do it, if you can). It doesn’t need to be super accurate, you should be able to tell the difference between 175 and 220, even if you miss or add a couple of beats.


^ this. Or if you have a watch with a proven optical wrist monitor, check against that.

Have you got the graph? A hardware issue might show up in that (might not though).

I have had weird spikes and dips before when the battery has been going, you can sometimes tell from the graph (i.e., it shoots up or down then stays completely flat for a while etc).

I had the same thing happen to me on my last ramp test. HR spiked up, stayed high for a good while and spooked me enough that it affected my ramp test quite a bit. All the while I was trying to take my HR the old fashioned way.

Thought I’d just keep an eye on it during workouts (didn’t replace my strap) and it hasn’t happened since, but still very scary when you read about the people that have a-fib.

Check it out with your dr. I’ve had an exercise induced tachycardia most of my adult life (infrequent) and recently had myself checked out by a cardiologist. My diagnosis turned out to be paroxysmal supraventricular tachycardia, and mainly just something of a nuisance. It can turn out to be something more serious. Worth the dr’s visit.


I have the same, and it manifests as a sudden brief spike on the HRM. But I’ve also had instances where my HRM itself was the source of the error, generally when the battery is running low. Moral of the story: don’t rule out equipment malfunctions, but definitely get anything heart-related checked out by a doctor.

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I have the same thing happen on every ramp test if I push to my limit. HR will climb steadily until about 175-180 which is my max and then quickly spike to 200. It scared me the first few times and I abruptly stopped the test even though I felt OK all things considered (end of ramp test). I certainly didn’t sense any odd symptoms. I did decide to push through a time or two to see what would happen and it would dip back down and then spike again but I never felt anything out of the ordinary. After that I just use the spike as the end of my ramp test even though my legs might have a few more seconds in them. I’m pretty sure I have had this happen on two different HR straps - a Garmin and a Wahoo - but I may double check that.

Not sure if this has been mentioned but I’d try putting dialectric grease on the terminals. I’m a fairly heavy sweater and during hard sessions I would get odd readings, the grease waterproofs the terminals and I haven’t had issues since.

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Definitely get checked out by a physician. Preferably someone who deals with athletes.

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