Pre diabetes - why is blood sugar high after exercising.

[Saur]

Hi all, I just received my meter and tested today. Fasting was 5.9 but after exercise for half an hour it went to 6.4. Why did it go that high? I know you should check 2 hours after eating but I was out and checked after 3 hours, does it matter? The reading was less at 5.3.

 

[ert]

When you exercise your muscles need more glucose to supply energy. In response, your liver increases the amount of glucose it releases into your bloodstream. If you don't have enough insulin or your insulin isn't effective due to insulin resistance your blood sugars rise.

 

[HSSS]

Also it appears the exercise was early morning after rising maybe? Levels can rise on waking for some of us (dawn phenomenon) and be nothing to do with exercise.

Also meters aren’t precise (I think it’s 15% error in this range). Just give trends. In reality both readings may have been similar in low 6’s.

By 3hrs I would want it to be significantly less than the usual 2mmol rise or less we usually advise at 2hrs having had the extra hour to continue falling. A fall in the postprandial reading after breakfast is often lower than the before or fasting as the (suitable) food switches off the dawn phenomenon for lots of people.

Also different forms of exercise has different effects. Hard intense exercise can raise figures for a while but the muscle it builds ultimately lowers numbers, something like a steady walk can drop it quickly as it doesn’t stimulate the liver dump but still uses some excess glucose floating about.

 

[Saur]

Also it appears the exercise was early morning after rising maybe? Levels can rise on waking for some of us (dawn phenomenon) and be nothing to do with exercise.

Also meters aren’t precise (I think it’s 15% error in this range). Just give trends. In reality both readings may have been similar in low 6’s.

By 3hrs I would want it to be significantly less than the usual 2mmol rise or less we usually advise at 2hrs having had the extra hour to continue falling. A fall in the postprandial reading after breakfast is often lower than the before or fasting as the (suitable) food switches off the dawn phenomenon for lots of people.

Also different forms of exercise has different effects. Hard intense exercise can raise figures for a while but the muscle it builds ultimately lowers numbers, something like a steady walk can drop it quickly as it doesn’t stimulate the liver dump but still uses some excess glucose floating about.

I like to exercise first thing in the morning, get it out of the way and then start the day. Will it be high after exercise everybody or could it change on a day to day basis?

 

[HSSS]

I like to exercise first thing in the morning, get it out of the way and then start the day. Will it be high after exercise everybody or could it change on a day to day basis?

Honestly I do little exercise and understand the theory but in practice I can’t say. I certainly wouldn’t avoid exercise in your shoes if I got into the routine. The rise isn’t much at all if anything, it came back down, and the overall benefit to health and probably diabetes long term is likely still there. Maybe see what your bloods do on a day you don’t exercise and over several more days and see what’s happening. The meters give trends not exact figures so look for patterns. Maybe there won’t be much difference and it’s dp not the exercise causing the very small blip.

 

[KK123]

Hi all, I just received my meter and tested today. Fasting was 5.9 but after exercise for half an hour it went to 6.4. Why did it go that high? I know you should check 2 hours after eating but I was out and checked after 3 hours, does it matter? The reading was less at 5.3.

A half point higher after exercise is nothing. Nobody's glucose levels stay at exactly the same number after exercise. I could understand if you had gone 2 or 3 points higher maybe but the difference between 5.9 and 6.4 is negligible especially given the fact that meters can be up to a point or two out anyway. Please don't let it put you off, I find mine spikes by around 1 point straight after exercise but comes down in an hour or two and is then at least 2 points lower for up to 24 hours afterwards.

 

[catinahat]

Hormones released when we are stressed (physically or emotionally) are the livers trigger to release some of its stored glucose. This is not new glucose, it is simply moving from your liver (where you can't see it) into your blood where you can see it and more importantly use it. The only exercise I do now is walking and I find that a gentle stroll will lower my levels but a brisk walk where I get out of breath and a little sweaty will cause them to rise.
In your case as the others have already pointed out a rise of 0.5 mmol is insignificant when you consider the
+/- %15 accuracy of the meters

 

[Guzzler]

Honestly I do little exercise and understand the theory but in practice I can’t say. I certainly wouldn’t avoid exercise in your shoes if I got into the routine. The rise isn’t much at all if anything, it came back down, and the overall benefit to health and probably diabetes long term is likely still there. Maybe see what your bloods do on a day you don’t exercise and over several more days and see what’s happening. The meters give trends not exact figures so look for patterns. Maybe there won’t be much difference and it’s dp not the exercise causing the very small blip.

I agree. Having viewed a lecture on ectopic fat in the liver and the muscle I think that a slight rise in bg is preferable wrt to risk than leaving the fat in the muscles which exacerbates insulin resistance.

Just wish I could do the excercise so as to get the glycogen moving and rid the muscles of fat.

 

[Saur]

I am just following the advise from the NHS Diabetes Prevention Programme to do the exercises as it will assist with losing weight and assist if you live sedentary life style. I was disappointed to see the figures rise from 5.9 to 6.4. I thought it was a big jump considering I hadn’t eaten anything. How many units make up one mm01? Sorry to be naive but new to this but also curious. How did it come to rise of only 0.5? Thankyou in advance members for your kind support.

 

[Saur]

Hormones released when we are stressed (physically or emotionally) are the livers trigger to release some of its stored glucose. This is not new glucose, it is simply moving from your liver (where you can't see it) into your blood where you can see it and more importantly use it. The only exercise I do now is walking and I find that a gentle stroll will lower my levels but a brisk walk where I get out of breath and a little sweaty will cause them to rise.
In your case as the others have already pointed out a rise of 0.5 mmol is insignificant when you consider the
+/- %15 accuracy of the meters

Thankyou

 

[Saur]

I agree. Having viewed a lecture on ectopic fat in the liver and the muscle I think that a slight rise in bg is preferable wrt to risk than leaving the fat in the muscles which exacerbates insulin resistance.

Just wish I could do the excercise so as to get the glycogen moving and rid the muscles of fat.

Thankyou.

 

[Saur]

A half point higher after exercise is nothing. Nobody's glucose levels stay at exactly the same number after exercise. I could understand if you had gone 2 or 3 points higher maybe but the difference between 5.9 and 6.4 is negligible especially given the fact that meters can be up to a point or two out anyway. Please don't let it put you off, I find mine spikes by around 1 point straight after exercise but comes down in an hour or two and is then at least 2 points lower for up to 24 hours afterwards.

Thankyou.

 

[Scott-C]

I was disappointed to see the figures rise from 5.9 to 6.4.

Hi, Saur, I wouldn't be disappointed by that!

Although modern meters look impressively accurate by having a decimal point, they have limitations just because of the technology involved.

Numbers like 5.9 and 6.4 should be interpreted as the same number, they're both "about 6", so there hasn't really been any change at all, so it would be incorrect to draw any strong conclusions on the effect of exercise based on those numbers.

If you had been seeing a change from 5.9 to, say, 8.3, that might be more significant, because one of them is "about 6" and the other is "about 8".

Good luck!

 

[Saur]

Hi, Saur, I wouldn't be disappointed by that!

Although modern meters look impressively accurate by having a decimal point, they have limitations just because of the technology involved.

Numbers like 5.9 and 6.4 should be interpreted as the same number, they're both "about 6", so there hasn't really been any change at all, so it would be incorrect to draw any strong conclusions on the effect of exercise based on those numbers.

If you had been seeing a change from 5.9 to, say, 8.3, that might be more significant, because one of them is "about 6" and the other is "about 8".

Good luck!

Thankyou this is really helpful.

 

[Tipe2too]

Also it appears the exercise was early morning after rising maybe? Levels can rise on waking for some of us (dawn phenomenon) and be nothing to do with exercise.

Also meters aren’t precise (I think it’s 15% error in this range). Just give trends. In reality both readings may have been similar in low 6’s.

By 3hrs I would want it to be significantly less than the usual 2mmol rise or less we usually advise at 2hrs having had the extra hour to continue falling. A fall in the postprandial reading after breakfast is often lower than the before or fasting as the (suitable) food switches off the dawn phenomenon for lots of people.

Also different forms of exercise has different effects. Hard intense exercise can raise figures for a while but the muscle it builds ultimately lowers numbers, something like a steady walk can drop it quickly as it doesn’t stimulate the liver dump but still uses some excess glucose floating about.

I was diagnosed T2 about 10 years ago and until about 1 year ago I did quite a physical job. Recently I have become more sedentary and obviously this has been playing on my mind.I have determined to get MUCH more active and am feeling good, if very sore through DOMS, hourly sessions in the gym twice weekly, one session of fairly gentle swimming and several moderate walks per week. I will persevere, hopefully increase activity when it becomes easier but here is the thing. My meter readings are almost double what they were pre new regime. They were around 6-7, now 12-16. I am utterly confounded and disheartened. I will be carrying on with the exercise even if my glucose is high as there are other benefits. Is there a scientific reason for these horrible numbers, am I going crazy.