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High sugar during exercise?

R

Rocinante

Well-Known Member
I'm prediabetic with an HBA1C of 42 (despite losing 2 stone and exercising much more frequently). As a result I've bought a Freestyle Libre, hoping to monitor what is causing spikes.

So far I've noticed that my cycles (60-70km of hilly road cycles) result in high blood sugar during the cycle. I understand this is caused by high adrenaline. Is there anything I can do about this or will this persist until I'm much fitter?
 
Rocinante said:
I'm prediabetic with an HBA1C of 42 (despite losing 2 stone and exercising much more frequently). As a result I've bought a Freestyle Libre, hoping to monitor what is causing spikes.

So far I've noticed that my cycles (60-70km of hilly road cycles) result in high blood sugar during the cycle. I understand this is caused by high adrenaline. Is there anything I can do about this or will this persist until I'm much fitter?
Click to expand...

For me personally, my blood sugars come down after 1 hour after my exercise.
 
Yea i consider it like eating a meal. If your working hard your body naturally releases the energy you need from its stores. It should drop when you finish.
 
I was really glad to see your post @Rocinante and all the replies. I’ve just had a similar shock. Although I knew BG goes up during exercise I was shocked to see it had risen to 8.7 today after boot camp ( higher than I’ve seen it since before diagnosis). It was very hard exercise, I’ve only been doing it a few weeks and today was the hardest yet. My BG is usually reasonably well controlled. It had dropped to 6.4 an hour later but wasn’t in the 5s (where I prefer it to be) for a couple of hours.
I think the Libre is great for getting this sort of data and you’ve reminded me I should stick one on before next week ( if I can walk again by then)
Does anyone know whether the height of the spike or the time it takes to come down again can be used to figure out how broken ones metabolism might be. How high do non diabetics go I wonder and what is a usual recovery time?
 
DJC3 said:
I was really glad to see your post @Rocinante and all the replies. I’ve just had a similar shock. Although I knew BG goes up during exercise I was shocked to see it had risen to 8.7 today after boot camp ( higher than I’ve seen it since before diagnosis). It was very hard exercise, I’ve only been doing it a few weeks and today was the hardest yet. My BG is usually reasonably well controlled. It had dropped to 6.4 an hour later but wasn’t in the 5s (where I prefer it to be) for a couple of hours.
I think the Libre is great for getting this sort of data and you’ve reminded me I should stick one on before next week ( if I can walk again by then)
Does anyone know whether the height of the spike or the time it takes to come down again can be used to figure out how broken ones metabolism might be. How high do non diabetics go I wonder and what is a usual recovery time?
Click to expand...
There’s too many variables. I usually drop within 30 minutes but if there’s some stress I.e. sore muscles , recovery time can be longer. I would say that recovery time, and not the spike, would be a better measurement of IR.
 
LaoDan said:
There’s too many variables. I usually drop within 30 minutes but if there’s some stress I.e. sore muscles , recovery time can be longer. I would say that recovery time, and not the spike, would be a better measurement of IR.
Click to expand...

Thank you, I was thinking along similar lines. I might ask my daughters if they’d mind doing a finger prick next week before and after, to see what effect it has on them. ( they are non diabetic and a lot fitter than me - but at least it will give me some idea)
 
DJC3 said:
Does anyone know whether the height of the spike or the time it takes to come down again can be used to figure out how broken ones metabolism might be. How high do non diabetics go I wonder and what is a usual recovery time?
Click to expand...

To add to what the others have said it might also be affected by fitness levels - if you’re doing something well out of your comfort zone BG will likely spike higher than if it’s a more normal activity.

I can give a couple of examples. When I first started playing walking football I was shocked at the post exercise rise. I’d been used to gentle walking bringing it down!

More recently, yesterday I walked a t full pelt for far longer than I normally do (and longer than I should have given the aches and pains this morning) and BG shot up far higher than it has for the past week or so (have been having BG issues, but starting to normalise) and stayed there for quite a while. Then plummeted when I sat down and relaxed/started walking more slowly.
 
When cycling my bloods tend to stay stable for the first hour then they just drop. I have a sugary drink to sip constantly, jelly babies which I have every half hour or so and I stop off every couple of hours and have a little bit of a carb bar.

When I play football I'm the opposite, I go up like you do with cycling. I have food before hand and I have a sports drink but bloods shoot up and it's a case of checking them more afterwards till they level off again.

Iv come to realise exercise affects us all differently and there's isn't a correct answer.
I can cycle 60 miles casually and be ok but then when I did it pushing hard with a mate I had major issues through the night with really low hypos

It seems to be trial and error with everything
 
@Goonergal and @MarkHaZ123 I guess it is all trial and error and like everything else with diabetes it seems to affect each individual differently. Certainly for me the boot camp on Saturday was more intense effort than I normally use. Definitely out of my comfort zone!
 
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