Manic heart rate

Not boffin but Mrs Boffin actually (I am sure he won't mind!)

I have been using a heart rate monitor for most of my runs over the last couple of weeks and I have been really horrified at how high my heart rate goes at the beginning of each run.
Even when I start out for a really, really slow run it leaps straight up to 180-205bpm. After about 2-3 minutes at that pace it slows down to a more sensible 140-150bpm for the rest of the run.
At first I thought it might have been the treadmill or the heart rate strap being a bit erratic but I have checked it on other equipment too.
I have been running for a couple of years and my resting HR is 60bpm so it is quite a dramatic leap!!

Is this normal?
Has anyone else experienced this?


  • I have experienced that, using a HRM.

    It comes as quite a shock.

    I have put it down to my body suddenly being asked to run fast, from a standing start. The heart is blind: it doesn't know what it being demanded of it next when it experiences sudden exertion, so it seems to go haywire at first until it settles down.

    After I noticed the phenomenon on my HRM, I changed how I start my runs. Instead of going fast to begin with, I go slow, pause, go slow, pause, go slow, pause, for a couple of minutes - so I'm gradually warming up into the run rather than racing away. I don't know if that is necessary, but that's what I tend to do now. No sudden burst of speed from a standing start.
  • I can't explain this if you're on a treadmill (unless your treadmill is in a cold garage, perhaps?), but if you're outside running, it is likely to happen most on colder days.

    It's called splanchic shunt or something like that. Basically when it's cold, the blood vessels contract so body temperature can remain stable. However, when you start your run, the heart will have to work harder to pump blood through the narrower blood vessels (because of the cold) - hence the elevation in heart rate. That is, until the blood vessels have opened up again as the body has warmed up and HR returns to normal. Normally happens for me if the temerature is lower than 6deg.C outside and it takes about 6 minutes for my heart to return to normal.

    Hope that helps. A guy I know who I work with who I know contributes on this forum told me about this, because I was equally concerned when it happened to me.
  • I appreciate the replies. Reassuring to know I am not the only one!!
    I have noticed it particularly on the early morning runs I have recently started doing for the FLM. As I have just crawled begrudgingly out from under the duvet and it is flipping freezing at the moment the splanchnic shunt theory makes sense.
    (And yes the treadmill is in a very cold garage - good call!!)

  • Boffin, I get extreme heart rate monitor readings. At rest around 45-50bpm, but typically 180 when running hard and up to over 200bpm flat out. I'm 42 years old.

    My doctor checked my blood pressure and found it to be very low. Typical adult would be 120/80 prrsssure; mine is 92/56. However as I have not had blackouts or other problems he told me to keep running!
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