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Exercise effect on blood glucose

TMR254

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Relationship to Diabetes
Type 2
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Two hours after lunch today my glucose level was 6.7, after having been snoozing in the chair! I spent the next two and half hours in the garden, cutting back bushes and tree branches, working like crazy. After that I was dead tired, I could barely limp back into the kitchen for a cup of tea. I measured my glucose level, just for the fun of it, expecting an all time low, and it was... 6.6! Almost no change. I mean, WTF! OK, I know these levels are approx., but after so much effort, and feeling soooo tired, I expected more of a change. How should I interpret these results?

Thanks.
 
Welcome to the forum @TMR254

Any glucose level between 4-7 is considered normal so to be back in range after your meal and after gardening is good news. Everyone’s levels change as our liver dribbles out glucose to keep us going.
I suspect anyone would feel tired after a couple of hours in the garden. I know that I do. It is an activity that I have to make adjustments to my insulin to manage. Your body is still releasing insulin so it sounds like whatever you are doing is working well and you are matching what you need from your pancreas to the amount of carbs you are eating.
 
Are you still on the Ebymect (Metformin / Dapagliflozin combo)?

It might seem slightly disheartening that your activity didn’t reduce your BG levels, but the body is amazing at balancing BG levels and can call on various stores of glucose if exercise is demanding enough.

In some ways it was a pretty ideal result - to be able to do all that activity and your BG levels to retain on-target is preferable to levels plunging down too low?
 
Are you still on the Ebymect (Metformin / Dapagliflozin combo)?

It might seem slightly disheartening that your activity didn’t reduce your BG levels, but the body is amazing at balancing BG levels and can call on various stores of glucose if exercise is demanding enough.

In some ways it was a pretty ideal result - to be able to do all that activity and your BG levels to retain on-target is preferable to levels plunging down too low?
Yes indeed. Thnx. Good point.
 
Now I have seriously reduced my carb intake I'm a bit nervous about going in the gym for the first time since the diagnoses, any tips I should follow
 
@TMR254 You may well reap the benefits of that exercise overnight and into tomorrow. I find that my levels don't go down much during exercise unless I have active meal time insulin in my system, but overnight the muscles I have been using will replenish their stores by sucking the glucose out of my blood stream and my levels drop.
I don't know if you routinely test on a morning when you wake up but I suspect that tomorrow morning your levels will be lower than they normally are.
For those of us who use insulin, we are advised (and can often see in our CGM results) that our exercise has a lowering impact on our BG for up to 48 hours afterwards. I was trimming my sister's horses hooves yesterday afternoon which is really hard work normally but very hard work yesterday as they are rock hard with it being so dry. Then I dashed home to help my partner exercise one of his horses as well as feeding and mucking out my own. I got into the house at 9pm crippled with my knees, back and hands aching and crawled into bed and reduced my overnight insulin. I went to sleep on 7.7 and still had to have a jelly baby through the night when levels got down to 4.2 and woke up this morning on 4.2. That jelly baby should have raised my levels by 1.5mmols, so in total my levels dropped 3.5mmols + the 1.5 that the jelly baby should have raised me so effectively that exercise lowered my levels by 5mmols overnight and my levels have been tootling between 4 and 6 most of the day today until tonight when it appears the effects of that exercise are starting to wear off a bit. I will still see a slight benefit from it tonight too. So please don't think that your efforts were in vain, you just didn't see them in real time.
 
Now I have seriously reduced my carb intake I'm a bit nervous about going in the gym for the first time since the diagnoses, any tips I should follow
As you are not on glucose lowering medication then your liver should do it's job and release glucose if your body needs it.
However it is worth being prepared and stay well hydrated and have something to hand just in case, like a couple of jelly babies. There is no reason it should be any different to before diagnosis. Your body will be using protein and fats for energy.
 
@TMR254 You may well reap the benefits of that exercise overnight and into tomorrow. I find that my levels don't go down much during exercise unless I have active meal time insulin in my system, but overnight the muscles I have been using will replenish their stores by sucking the glucose out of my blood stream and my levels drop.
I don't know if you routinely test on a morning when you wake up but I suspect that tomorrow morning your levels will be lower than they normally are.
For those of us who use insulin, we are advised (and can often see in our CGM results) that our exercise has a lowering impact on our BG for up to 48 hours afterwards. I was trimming my sister's horses hooves yesterday afternoon which is really hard work normally but very hard work yesterday as they are rock hard with it being so dry. Then I dashed home to help my partner exercise one of his horses as well as feeding and mucking out my own. I got into the house at 9pm crippled with my knees, back and hands aching and crawled into bed and reduced my overnight insulin. I went to sleep on 7.7 and still had to have a jelly baby through the night when levels got down to 4.2 and woke up this morning on 4.2. That jelly baby should have raised my levels by 1.5mmols, so in total my levels dropped 3.5mmols + the 1.5 that the jelly baby should have raised me so effectively that exercise lowered my levels by 5mmols overnight and my levels have been tootling between 4 and 6 most of the day today until tonight when it appears the effects of that exercise are starting to wear off a bit. I will still see a slight benefit from it tonight too. So please don't think that your efforts were in vain, you just didn't see them in real time.
Thanks. Worth bearing in mind. Yes I do measure the glucose every morning. It was slightly lower I guess.
 
Hard physical exercise raises mine for a while but walking lowers it. I think that is normal.
 
I just done my first big walk around the estate, felt great
Walking had an amazing effect on my BG levels. I managed to get off the Metformin and into remission (starting BG 108!). I walked every night after my evening meal and my BG stayed almost flat.
I have suffered with plantar (foot) problems over the past few months and had to stop the walks and its really had an effect on my BG levels. So if you can keep it up i encourage you do so. You will also feel much healthier and maybe lose weight and improve blood pressure like i did.
 
Now I have seriously reduced my carb intake I'm a bit nervous about going in the gym for the first time since the diagnoses, any tips I should follow
Take a propietary energy drink with you: I use Science in Sport Go when I'm cycling and taking sips every so often keeps my blood sugar where I want it to be.
 
Take a propietary energy drink with you: I use Science in Sport Go when I'm cycling and taking sips every so often keeps my blood sugar where I want it to be.
That may be sensible as an insulin dependant Type 1 but not necessarily for a Type 2 who is not at risk of hypos.
 
Thanks. Worth bearing in mind. Yes I do measure the glucose every morning. It was slightly lower I guess.
I was advised ages ago to “do something for 15 minutes after a meal -don’t sit down”.
I find this very effective (but don’t always do it!!!!)
 
That may be sensible as an insulin dependant Type 1 but not necessarily for a Type 2 who is not at risk of hypos.
Well I used it when cycling long before I developed diabetes: it keeps anyone's blood sugar at an optimum level when exercising hard. Keen cyclists know of something called 'hunger knock' or 'the bonk', which is when one runs out of available blood sugar.
 
Well I used it when cycling long before I developed diabetes: it keeps anyone's blood sugar at an optimum level when exercising hard. Keen cyclists know of something called 'hunger knock' or 'the bonk', which is when one runs out of available blood sugar.
My non-diabetic partner "bonked" on his bike. Thankfully, it was on his turbo trainer doing a long steep uphill route on Zwift over a couple of hours.
He said he felt dizzy and had to get off the bike. After he felt he had recovered, he took a BG reading - 2.9 and that was after recovery.
I often mention this when people say that you only get hypos if you take insulin. That said, you need to really push it without any fuelling to bonk. I don't know of anyone who has bonked from gardening.
 
Hard physical exercise raises mine for a while but walking lowers it. I think that is normal.
I am not sure that is normal.
It depends upon a number of things such as the type of exercise, how long you do it and how stressed your body is.
I exercise regularly so although not a professional athlete, I am fitter than most people. My cycling is a good example of how these things can affect me.
- if I go for a gentle pootle along a flat canal tow path, my BG barely changes
- if I do a tough 45 minute Spin class, my BG plummets
- if I do a hard slog up a steep hill against the wind and rain, my BG rockets.
I would describe the Spin class and the uphill as "hard physical exercise" but my body is more stressed with the uphill whereas the Spin is pure cardio.

As someone who manages their diabetes with insulin, the amount of active insulin I have in my body will also make a huge impact.
And although someone without diabetes will see variations with their BG, it is unlikely to be as pronounced.
 
My non-diabetic partner "bonked" on his bike. Thankfully, it was on his turbo trainer doing a long steep uphill route on Zwift over a couple of hours.
He said he felt dizzy and had to get off the bike. After he felt he had recovered, he took a BG reading - 2.9 and that was after recovery.
I often mention this when people say that you only get hypos if you take insulin. That said, you need to really push it without any fuelling to bonk. I don't know of anyone who has bonked from gardening.

Bonking on a bike sounds a bit uncomfortable.

The same happens to me after a vigorous walk, especially up hills. Walking up Vesuvius for instance a few years back.
If I combine exercise with carbs it's even worse. I thought my crisps and alcohol (Beer) plus walk home low was caused by alcohol, but I get the same effect with just carbs and a walk.

It generally pops back up to between 4-7 within half an hour, but on one occasional it stayed low all night.
 
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Well I used it when cycling long before I developed diabetes: it keeps anyone's blood sugar at an optimum level when exercising hard. Keen cyclists know of something called 'hunger knock' or 'the bonk', which is when one runs out of available blood sugar.

But @Ian Robinson is going to the gym so very unlikely to "bonk", even less so as his mobility is somewhat limited.
I just think there is a temptation here on the forum to encourage people with Type 2 diabetes, who are not at risk of hypos, to take sugary drinks or snacks when they exercise which partly undoes what they are trying to achieve and perhaps also fosters a fear of having a hypo.
 
I am not sure that is normal.
It depends upon a number of things such as the type of exercise, how long you do it and how stressed your body is.
I exercise regularly so although not a professional athlete, I am fitter than most people. My cycling is a good example of how these things can affect me.
- if I go for a gentle pootle along a flat canal tow path, my BG barely changes
- if I do a tough 45 minute Spin class, my BG plummets
- if I do a hard slog up a steep hill against the wind and rain, my BG rockets.
I would describe the Spin class and the uphill as "hard physical exercise" but my body is more stressed with the uphill whereas the Spin is pure cardio.

As someone who manages their diabetes with insulin, the amount of active insulin I have in my body will also make a huge impact.
And although someone without diabetes will see variations with their BG, it is unlikely to be as pronounced.
Perhaps the word normal i used was not ideal perhaps should have said not unusual for BG to rise after strenuous exercise. Happens to me all the time but gentle/moderate exercise like walking lowers my levels or stops them rising after eating.
 
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