Reverse foot-on-the-floor phenomenon?

I notice if I’m not moving – I’m in bed, or I’m sitting in my chair reading in the evening – as soon I get out of bed (regardless whether it’s as soon as I wake up or after I lie there for a while) or get out of my chair, my CGM blips down for the next one or two readings and then returns to where it was. With no 15-minute lag.

Here’s a morning. I got up at 8:22.

And here’s an evening. I’d been reading for a couple of hours, and then at 10:38 I got up and moved around. (The trace does return to where it was. Sorry, I took the photo too soon.)

These are just two examples of something that happens over and over and over again. I’m just curious why it happens, and why there’s no 15-minute lag. Anyone have any ideas?

(BTW, these flatlines are not that common. It’s just that the absence of noise highlights the blip down.)

@Beacher I have a very similar problem. As soon as I wake up, my bG starts to go down. But it does not return to normal until I eat. The only time I get a 15 min or so change is when I take a shower, the dexcom blips up for about 15 min and returns to normal after I’ve gotten dressed.

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Because there is no lag, would you suspect it is an issue with the CGM and not your actual BG?

Maybe worth doing some BG tests before you get out of bed and then soon after you get out of bed to see if there is anything noticeable.

I get mini-spikes frequently when I wake up. But it doesn’t seem to happen when I am below 90.

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I’ve wondered about that – that when I move significantly after being immobile for a while, the interstitial fluid sloshes around, and that briefly alters the reading. Can’t find any explanation of why, or why it goes down and not up.

I’ll try blood testing.

This isn’t typically my experience, but I notice this sometimes if I am immobile, running high and correct. If I am on a long drive and have a high BG, corrections just seem to stabilize my BG but won’t bring it down as long as I’m driving. The minute I step out of my car my BG starts to plummet. Ive seen the same thing if I wake up early high, take a correction and go back to sleep. The Dexcom line will stop rising but just stay high until I get up, at which point I plummet.


@beacher - when I get out of bed in the morning my BG usually drops. I have checked this with BG tests.

Then about 1 hour later I have a higher basal rate (increase of 160%) for about 2 hours to prevent a later morning rise, which will start to occur about 2 hours after I get up.

The way I see it is my liver’s response to waking up is quite delayed. I am definitely not a morning person. It takes great effort to get going in the morning :smile: