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Are Blood Sugar Spikes Dangerous When Exercising?

P

pkirk25

Member
Messages
10
Type of diabetes
Type 2
Treatment type
Tablets (oral)
Hello all,

I use the Abbot Freestyle Libre v2. The readings are not accurate in that they are about 2 below what the finger prick shows. But the information is still useful to me as it shows what I can and can't do.

In the image below, the correct reading would be just under 15 mmo/L.

Provided I take my Glucophage (a kind of slow release metformin) tablets and stay sensible when it comes to food, my blood glucose levels are generally in range. However, when I go for a run, I get this huge spike. I go out for the run first thing in the morning so this is a blood glucose spike when fasting. It falls like a stone after I stop running.

I've googled a lot and I get lots of reports that the spike is caused by adrenaline when I am under pressure while running hard.

I know blood spikes after eating are dangerous. Is this blood spike while exercising also dangerous?

Thanks in advance.

Patrick
 

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It is not only adrenalin, of which most people forget about, but also other hormones you need for doing stuff. However, as far as my experience or the things I 've discovered is something called glucogenisis.
When your energy stores, when you eat carbs, go down, just before they deplete, your liver will automatically give you a boost of glucagon/ glucose to restore energy levels called in non medical terms as a liver dump.

With T2, the unnecessary spikes is what you need to avoid as well as certain carbs. Keeping your blood glucose levels near normal levels as much as possible, is the best way forward.

Exercise is important and individual, some can do a lot, some can't. I can't do strenuous exercise because of that spike, it will eventually lead to a hypo.

So don't stop exercising but find out which exercise doesn't mean you spike consistently high.
 
Have you tried running before dinner at night instead to see if that makes a difference, I stopped running in the morning as mine would spike too, maybe worth a try
 
I hear what you say about Libre accuracy. However, I am surprised you can quote it as always around 2 under. In my experience, the accuracy is a percentage so the higher my levels, the further out the readings are. In addition, CGMs are calibrated for most accuracy at “normal” levels and over 10, it may as well make up numbers.
As for the spike, I wonder if it is related to dehydration which is another thing that affects accuracy. I know it is difficult whilst running but could you check with a finger prick. For example, set an alarm when Libre reads over, say, 12 and then stop runn to check.
Basically, what I am saying is check the spike is really there before trying to get rid of a ghost.
 
Lots of useful ideas and suggestions. Thanks. Interestingly, I tried asking the new Bing AI search engine "are blood glucose spikes when exercising dangerous for someone with type 2 diabetes?" It replied Yes and this thread was the link justifying that assertion.
 
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