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High BS and exercise

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daisyindevon

Member
Messages
5
Hi, I've been low carbing for the last couple of months with good success. I've lost 28lbs and I@m feeling much better overall but I have a problem which I hope someone can shed some light on. I've been trying to exercise regularly - I walk for about an hour every day and swim for about half an hour five times a week. The only problem is that after I exercise, my BS shoots up by as much as 5 whole points and takes about 3 hours to come down, even if I don't eat anything afterwards. For example, my BS after breakfast this morning was 6.8 (I had boiled eggs). I went swiming about 2 hours ago and afterwards, it had risen to 11.8 and it's still up at 11.2 ten minutes ago. This rise seems to happen every time I exercise and from other posts I've read, exercise should be bringing my BS down! Can anyone tell me what's going on here please? I know I need to exercise but I'm concerned that I'm getting these big spikes. It doesn't seem to make any difference what I eat or when I exercise.

Thanks

Daisy
 
From the quick read, I would take a guess at it being something to do with the differences between anaerobic and aerobic exercise.

Take a look at the RUNSWEET website, sports info for diabetics.
 
Hi Daisy.

I have two tentative ideas on this. One possibility is that perhaps when your blood sugar drops below a certain level your liver may be doing a 'dump' as you exercise to try and bring it back up. (Similar thing happens overnight with some people and results in the 'dawn phenomenon')

The other possibility is that exercise can mobilise toxins out of the muscles etc., some of which could possibly be latent stored sugars and/or glucose. They would float around your bloodstream until your body can dispose of them.

These are only theories, as it seems to be a bit of an unknown phenomenon, but no less feasible than anything else.

http://www.drmyhill.co.uk/wiki/Detoxifi ... n_overview
 
I agree with the idea of the the liver releasing glucose particularly if there is no readily available glucose from food intake. The body cannot process fat quickly during exercise and so it will release glycogen for immediate energy.
I know you said this happens with everything but I also note you mentioned eggs. Personally I know I need to use some insulin for all proteins but for some reason eggs have quite a high demand, I have read of this affecting others... but not everyone. What happens after eggs and no exercise?

As for the Myhill site, read it , she certainly has a following, but she wouldn't be my first choice for information.
General Medical Council, interim orders panel:
http://www.gmc-uk.org/static/documents/ ... h_2011.pdf
 
Personally, I think that the body would only turn to glucose for its fuel if it is in glucose-burning mode because it would have to change over to fat-burning and that can take some time to achieve.

Because I am in fat-burning mode my body automatically, and immediately turns to fat for its fuel source, which is why I no longer get hypos or dawn phenomenon and my Bg levels remain pretty stable.

It can take from a few weeks to up to 4 months for the body to change over to ketosis, but only if the carb level is low enough to force the change.

It seems to me that when in glucose-burning mode the body doesn't burn fat very well, and when in fat-burning mode it doesn't burn glucose very well.

I wonder if there is a way of getting it to do both very effectively!
 
AliB said:
Personally, I think that the body would only turn to glucose for its fuel if it is in glucose-burning mode because it would have to change over to fat-burning and that can take some time to achieve.
Click to expand...

I thought the human body only burns glucose and that whether it gets that glucose from carbs or fat it still uses glucose.

Daisy do you get high readings if you just do gentle exercise like walking, often gentle exercise will have a lowering effect and strenuous exercise will tend to push levels up this is because with gentle exercise the muscles will use stored glucogen for their needs but if worked harder then the liver will dump its stpre to meet demands.
 
The body can get glucose from protein but not fat. Beta-oxidation of fats will also provide energy, but this cannot be used to make glucose.
 
We use all sources for energy, all the time. During the 4 hours after a meal containing 100g glucose its estimated that energy is supplied by 60% CHO, 25% fat and 15% protein
During exercise after an intial demand for glucose to get going, if we then exercise at low intensity we use the greatest proportion of energy from fats . As exercise becomes more intense, more energy from glucose is used.(and demanded) , we still continue to burn fats though.
If we get to be flat out at near max heart rate almost all the fuel needed is from glucose. Then there is a big demand, thats why anaerobic exercise can increase glucose levels.
(I started writing a complex explanation then found this:
http://www.dummies.com/how-to/content/b ... rning.html

What's a gentle walk in the park for one person though could be quite intense for a less fit person. Some people when they start exercising are working at quite a high heart rate. It is at above about 60% of maximum heart rate that the demand for glucose gets higher. If you haven't been exercising you could reach this level with a moderately intense walk. Exercising regularly ie training means we get more efficient and don't demand so much glucose at lower intensity levels. As we get fitter our resting heart rates should fall.

In T2 diabetes there often seems to be a bit of an imbalance ie glucose is demanded but too much glucose is released; the classic liver dump' . Basically, the 'glucostat' of insulin/glugagon aren't working to balance each other. It could also be that the glucose though present, doesn't get into the cells, because cells are very insulin resistant .(though during exercise this shouldn't be problematic since insulin is not needed to get glucose into the cell when exercising... unless glucose levels are very high before exercise and that's a whole different scenario)

(have you any idea where your blood glucose level is during or at the end of the exercise?, this could make a difference to possible solutions)

The only practical ideas are and just ideas (sorry)
a) keep on :exercise does reduce insulin resistance and should lower levels over all.
b) maybe walking/ swimming at a lower intensity until you are more 'trained'. You could get a heart rate monitor and see how intense you exercise actually is.
c) (and sorry this isn't a low carb piece of advice!) It might help to eat a very small amount of carbs (10-15G), such as from fruit before exercise to help fuel the exercise or a similar amount during the period imediately after exercise when little or no insulin is needed to use it.(thus if there is a dump; preventing it)
 
Could it be though that if an individual is insulin resistant, although their body is pushing out glucose to fuel the muscles, the muscles can't use it?

Perhaps in that case they are actually burning fat instead and the glucose is not achieving anything and is just floating around in the bloodstream.

Sid, the body can use either glucose as fuel, or ketones from fat-burning. When marathon runners hit 'the wall' that seems to be the point at which their glucose stores run out and ketosis takes over. It can knock them back a little because the body takes a few seconds in that case to change over.

Charles Washington has found during long-distance running that because he is very low-carb and in fat-burning mode all the time, he doesn't hit 'the wall' at all.

The relatively small amount of glucose that is needed in the body it can manufacture from proteins using a process called gluconeogenesis.

I do wonder if in those of us with imparied glucose metabolism, the changeover between glucose-burning and fat-burning doesn't work as efficiently as in those who are non-diabetic and used to changing from one source to another.

But that is only my opinion.
 
Sorry Daisy, this isn't relevant to your question :oops:
Charles Washington has found during long-distance running that because he is very low-carb and in fat-burning mode all the time, he doesn't hit 'the wall' at all.
Click to expand...
I can't find any mention on his blog of his having run more than a half (13 and a bit miles) so he's about 7 miles short. Prior to T1 I ran a couple of half marathons on nothing more than water.
I didn't hit the wall in the London Marathon in April either :D
You don't have to be a low carber to use fat, that's where most of the energy comes from in a long distance run.You also need to use glucose (from glycogen) to actually be able to oxidise fat. Glycogen stores are limited and can run out at about 20 miles or before if the person has been running too fast (for them) in the early stages or indeed if stores are low in the first place.
http://www.marathonandbeyond.com/choices/latta.htm
 
Thanks for your replies. Will have to do some catch up reading as a lot of it went completely over my head - sorry, I'm not very 'technical' and you all seem to know so much about the science bits :shock: . The interesting thing is that absolutely ANY exercise whatsoever pushes my BS up - even a stroll around town or a bit of housework puts it up 2 or 3 points. Is this because I am very overweight? Obviously, I'm not going to stop exercising but I just wonder if these spikes are an indication of something nasty lurking in the background.
 
Daisy, do you find it makes you breathless when you walk or do the housework etc ?
 
A little if it's a bit strenuous. I guess that's because I'm not fit and overweight. My blood pressure has always been normal (at least that's one thing I haven't got a problem with!).
 
I think that might be part of the reason for your glucose levels rising, what we called anaerobic exercise is basically exercise that makes you breathless. Try to take things gradually, not trying to do too much too soon. As you lose weight it should become easier. If you get very breathless though it might be a good idea to mention it to your doctor (no special reason, it's just belt and braces to make sure they know everything!
 
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