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Exercise and rising BG - confused!

C

Claire

Well-Known Member
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110
Location
United Kingdom
Hello

I have noticed since changing to basal bolus that my BG rises slightly during exercise - I am generally around 5/6 when I start and after 1 1/2 hours in the gym mixture of cardio and weights I am around 7/8. I do not need to take on any more carbs while I am working out. This wasn't what happened with me before! Is it OK?

I have done a lot of reading and have seen that blood sugar can rise if there is not enough insulin in the body, but usually the examples that are given are when the BG is above 15, which mine isn't, it's still staying pretty much in the good range. I usually go to the gym before breakfast or after something low carb such as veggie juice, so I haven't had any Novorapid that day - but if I give myself insulin surely I will be going hypo during exercise?

Not sure what to do, any advice appreciated :)
 
Hi Claire

Could it be that the food/veggie juice is taking 2½ - 3 hours to fully get into your system, therefore even with the exercise your BS level has risen?
You could eat the same thing one day and not go to the gym and test after a couple of hours to see what result you get. The next day, do the gym thing and test. Compare results.

My BS was 8 so I went for a walk, came back and re tested and it was 9.something, so I thought ***?!
Other times my BS has been high and I do a little exercise (cut the grass) and the next thing I know is it's 3.2 and time for some carbos. :)

It's a constant battle as BS levels can sometimes behave unpredictably. If I catch a cold it tends to push my sugar levels up.

I'd try doing the gym and not doing the gym, and eating exactly the same thing at the same time, and compare test results. You may need to do this a few times (sorry, but it'll be worth it) to be sure.
 
One more thought - Eating carbs will always raise your BS level to some degree depending on what and how much. After eating and doing your exercise you find your BS to be 7/8 that's not too bad really. The food has kept you going through the exercise.
 
when you exercise your body will provide itself with glucose. this will raise BG levels somewhat temporarily. I tend to be high for about 3 to 4 hours then it plummets and I'll need to eat something as my muscles have taken all the available glucose for munchies.
 
I am not well read on exercise physiology. But as you undertake your exercise, your stress hormones (eg adrenaline, steroids etc) raise your BS (as it does in illness). This mobilises sugar stores . Your muscle sugar store is in the form of Glycogen. This is replenished a few hours after which can lead to hypos. So you need a snack at that point. Think of exercise as burning calories and not controlling blood sugar.

Increased muscle mass is a way of allowing Metformin to be more effective.


From memory, my dietician suggested a target range of BS for exercising. Not below 6mmol (risk of hypo). And not above 16 (not enough insulin on board to allow good muscle function).


Marty B
 
My two pence worth is that you are eating, and not taking on any insulin, so your blood sugar is rising. It sounds to me like you are doing exactly the right thing though! If I had any carbs and no insulin my blood sugar rockets, so the exercise is doing its stuff. You are also exercising without a hypo......personally, I think you are doing the right thing, and you are making me feel guilty for being a stranger in the gym!

Jill
 
I'm type 2 on 1 x Metformin daily and I have noticed that my BS increases after an hour of exercise. I think the increase can be down to the liver pumping out extra glucose to support your exercise. After having a meal, after my exercise, I have also noticed that my BS drops more than without exercise. So it could be a delayed action after the liver has depleted some of its reserves. I'm no expert, but to me it seems to make some sense. In general exercise makes by BS more erratic, and after 2 months at 3 times a week I must say I have not noticed significant drop in BS, although I do feel very much healthier.
 
I think that what you are doing seems to be working perfectly for you so I wouldn't fix what isn't broken. Do you fidn that your blood sugar stays pretty stable in the hours after the gym?

I fidn that my blood sugar soars with certain types of exercise, e.g. when i play football i can start at 5-6 and by the end of the game I am 17-20, when I play badminton i fight to keep my blood sugar above 5 and constantly have hypo's. so for me different types of exercise have different effects aswell.
 
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