heart rate spiking at start of run....?

[philcray]

I have been monitoring my running heart rate for some time now following some issues which have knocked my running speed back significantly. I set off very slowly to warm up but my heart will spike up quickly to c160bpm and then remain there for almost a mile. It then drops back to c115/120 where it remains for the rest of the run (generally 10-15km). It does this every time, dropping back at the same place as I hit 1 mile.

Anybody else have a similar experience?

[bigandclever]

All the time, if you don’t warm up properly. It’s to do with your muscles having to work anaerobically because you haven’t opened up your capillaries yet, so you get this double-whammy of blood being diverted from your core & major organs to your muscles that were at rest, and your muscles not being geared up to accept it. Your heart rate going up is an indicator your muscles are working anaerobically. Once you get aerobic, your heart rate sorts itself out.

Starting to run isn’t a good warm-up for running

Edited by bigandclever on Thursday 3rd September 18:28

[frisbee]

Optical sensor? They can be a bit flaky when exercising. My heart rate recorded by my watch takes a long time to rise while running and I get an unexpected spike every other run or so.

My cycling chest strap correlates a lot more closely to perceived effort.

[anonymous-user]

Mine doesn’t do that, no particular warmup before runs (apart from before races in the olden days !)
Apple watch

[Smitters]

I would almost certainly say it's the sensor. Are you using wrist or a chest strap. My preference for accuracy is a chest strap as even clamped down a notch, as Garmin suggest, my wrist sensor has a mind of it's own.

Either way, the improved reading is likely down to moisture, making the contact cleaner and the reading more precise.

With my chest strap, I run it under a tap to get the sensors wet, then put it on, the run my hand under the tap and run a finger between the sensor pads and my chest to make sure the contact is wet. Since adopting that strategy I rarely get odd readings, except when the chest strap battery goes low.

[bigandclever]

Smitters said:

I would almost certainly say it's the sensor.

Maybe it is, but I’d say it’s a normal physiological response, particularly with the regularity of it. OP is describing what happens during splanchnic shunt. It takes, very broadly, 8 to 10 minutes to go from rest to sufficiently warmed-up .. meaning muscles that were at rest and being asked to work anaerobically are now able to work aerobically. Which, no offence to OP intended , will be about the same time it takes to do a mile of slow running.

Erratic readings point more towards sensor irregularities.

[philcray]

Thanks for the feedback. The readings are from a chest strap and they are consistently repeated so I do not think it is a fault with the sensor. It does point to the anaerobic warm up of muscles, it takes me about 8,30 for the first mile as I take it easy so that all ties in. Hopefully nothing to worry about!

[Smitters]

bigandclever said:

Smitters said:

I would almost certainly say it's the sensor.

Maybe it is, but I’d say it’s a normal physiological response, particularly with the regularity of it. OP is describing what happens during splanchnic shunt. It takes, very broadly, 8 to 10 minutes to go from rest to sufficiently warmed-up .. meaning muscles that were at rest and being asked to work anaerobically are now able to work aerobically. Which, no offence to OP intended , will be about the same time it takes to do a mile of slow running.

Erratic readings point more towards sensor irregularities.

Fair enough. Those are big words I've never heard.

My sensor readings when dry are not erratic. They're just high. So effort at should yield 130bpm will display 170-180, but will not jump between the two.

[geeks]

You aren't taking a caffeine booster gel or something before starting are you? Mate of mine was having a similar issue, turns out that was why. Just a thought.

[ajap1979]

Mine spikes every time I run past the hospital. Must be something to do with some of the equipment they have there

[Bad Ash]

Do you put water on the strap before you put in on? The instructions for my Garmin say to do that. I believe it needs some moisture to work well, so it might that if you aren't wetting it, it takes about a mile for you to start sweating?

[CarlosFandango11]

Bad Ash said:

Do you put water on the strap before you put in on? The instructions for my Garmin say to do that. I believe it needs some moisture to work well, so it might that if you aren't wetting it, it takes about a mile for you to start sweating?

I put some ECG gel on my chest strap. Otherwise my heart rate on my garmin can incorrectly spike early in a run until I sweat enough to get a goof contact.

[philcray]

Thanks, I have tried the chest strap both wet and dry and it seems to make no difference, still spike at start then settling down, so I have to assume it is working correctly.