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Type 2 Glucose spikes after exercise?

ShelleyDubs

ShelleyDubs

Well-Known Member
Messages
70
Type of diabetes
LADA
Treatment type
Insulin
Hello, I am T2 for 18 months now and always managed with LCHF to stay in 4-7 range. No meds. I went cycling for an hour today and have had readings of 8+ fasting. Is this something that happens? Really struggling to get this spike down. Thank you.
 
ShelleyDubs said:
Hello, I am T2 for 18 months now and always managed with LCHF to stay in 4-7 range. No meds. I went cycling for an hour today and have had readings of 8+ fasting. Is this something that happens? Really struggling to get this spike down. Thank you.
Click to expand...
Hi ShelleyDubs,
Don't panic. There are many reasons why your fasting BG reading may be higher. These include:
Exercise - your liver decide to help you out by giving you a dump of glucose - just like you get with the 'Dawn Phenomenon'.
Infection/illness
Stress
Lack of sleep
A bad test strip
 
ShelleyDubs said:
Hello, I am T2 for 18 months now and always managed with LCHF to stay in 4-7 range. No meds. I went cycling for an hour today and have had readings of 8+ fasting. Is this something that happens? Really struggling to get this spike down. Thank you.
Click to expand...
Hello Shelley, I too am struggling with my bg rising after exercise. It seems so unfair! I never exercise fasted, but my bg seems to rise whenever I get physically tired. It happens after running, resistance training and even just walking wearily up from town with a rucsac full of heavy shopping. I am intending soon to affix a Libre sensor to give me a continuous readout of my bg for 2 weeks, in the hopes of seeing exactly when the rises occur. Again as for you, once my bg has gone up, it takes ages to go down again. My suspicion is that I just don't produce enough insulin to cope.

You could try avoiding fasting and see if that helps. I find I have to eat something on rising as otherwise my bg (whether lowish or highish) will often go on rising until I do. Maybe exercising fasting gives your liver the idea that you need some glucose in your blood stream.
 
Alexandra100 said:
Hello Shelley, I too am struggling with my bg rising after exercise. It seems so unfair! I never exercise fasted, but my bg seems to rise whenever I get physically tired. It happens after running, resistance training and even just walking wearily up from town with a rucsac full of heavy shopping. I am intending soon to affix a Libre sensor to give me a continuous readout of my bg for 2 weeks, in the hopes of seeing exactly when the rises occur. Again as for you, once my bg has gone up, it takes ages to go down again. My suspicion is that I just don't produce enough insulin to cope.

You could try avoiding fasting and see if that helps. I find I have to eat something on rising as otherwise my bg (whether lowish or highish) will often go on rising until I do. Maybe exercising fasting gives your liver the idea that you need some glucose in your blood stream.
Click to expand...

Thank you Alexandra. I’ll definitely try eating something to halt the rise and see what happens then. I have a libre sensor on and it’s quite a revelation what your levels do throughout the day and night. Certainly worth it. I have been using fasting to keep my levels down but it’s just not working at the moment. So frustrating. It worked before. Ah well, all part of the journey I guess! Thanks again for sharing and good luck with your libre. I find it is worth the money.
 
ianf0ster said:
Hi ShelleyDubs,
Don't panic. There are many reasons why your fasting BG reading may be higher. These include:
Exercise - your liver decide to help you out by giving you a dump of glucose - just like you get with the 'Dawn Phenomenon'.
Infection/illness
Stress
Lack of sleep
A bad test strip
Click to expand...

Thank you! I know it means well, but that liver is a pain isn’t it? Also, I can probably add stress to my list as I started a new job recently and it’s not that great. Also I have a lack of sleep. No wonder I’m spiking. I’ll try eating something to halt the liver in it’s tracks. Not sure how to de-stress if exercise makes me spike as well. Hmm. I’ll keep trying things out and see what happens. Good to hear from you - I’ll certainly try to be calm about it and just not worry about what I can’t control. Thanks again.
 
Hi,

I also find that exercise increases my levels. I'm working on the hope that this is coming from the glucose already stored in the body so that eventually (in a few years) this won't happen as I won't have as much glucose stored. I don't really know if there is any basis to that hope but it makes sense to me.
 
ShelleyDubs said:
Hello, I am T2 for 18 months now and always managed with LCHF to stay in 4-7 range. No meds. I went cycling for an hour today and have had readings of 8+ fasting. Is this something that happens? Really struggling to get this spike down. Thank you.
Click to expand...

If you exercise while fasted or after an over night fast, then there is no food there to provide the energy when it is suddenly required, so your liver will release glucose to keep your system running as it should. A lot of people find that their level rises as soon as their feet hit the floor first thing in the morning, so exercising on top of that can make the spike even great. Personally, I don't exercise on an empty stomach.
 
Tophat1900 said:
If you exercise while fasted or after an over night fast, then there is no food there to provide the energy when it is suddenly required, so your liver will release glucose to keep your system running as it should. A lot of people find that their level rises as soon as their feet hit the floor first thing in the morning, so exercising on top of that can make the spike even great. Personally, I don't exercise on an empty stomach.
Click to expand...

I have recently started doing exercise whilst fasted and notice that it causes quite a large spike. In practise the amount of the spike is indicative of how hard I worked which is a good thing. If you can, one way to bring down a high spike after exercise is a cold shower ( I swim in a cold pool) that seems to work for me quite reliably.
 
lol it isnt the liver being a pain , it is doing exactly what it is supposed to be :). it will be more our insulin resistance that causes the glucose to stay up once released. Also worth noting that upon reversal or part reversal of insulin resistance, you will notice lower spikes , I remember when I toyed around with a freestyle libre, the dawn phenomenon would only result in a slight increase and intense exercise eg pull ups would have it go up to 5.5 max and right down again quickly after practicing months of sustained high fat low carb.
The better your insulin resistance gets from reduction of overall insulin release, the lower the glucose spikes.

Lastly , cortisol levels also fluctuate during the daily cycle and this will also affect BG and more so if we are insulin resistant. Also illness will affect BG. The more inflamed and insulin resistant we are, the more ill we get.

Interesting pdf and thanks for sharing and useful as a guide. Fundamentally flawed in some areas but a handy guide nonetheless. The first being that fat causes insulin resistance. Terribly simplistic statement and doesnt really deal with the type of fat consumed. Lastly eating fat doesnt cause insulin resistance to any of the same extent that eating excess carbs does. To highlight fat as causing insulin resistance ignores the big giant elephant in the room is, well, disappointing, so I thought I'd point that out. Of course it is best to avoid inflammation causing seed oils high in PUFAs and other harmful chemicals.
 
For me the type of exercise matters in terms of spiking and as I’ve got fitter the spikes have reduced. Weights always push levels up. Less so at the end of the day than the start, but up they go. Similarly playing walking football (more energetic than it sounds) or football involving some running, or doing a long, very fast paced walk, will push levels up. However, there is always a corresponding reduction in BG levels a couple of hours later and over time, my overall BG levels go down a notch as exercise increases and becomes part of my daily routine.

Swimming, Pilates and moderate to slow paced walking all reliably bring BG down.

I regularly exercise fasted - have completed several long, moderately paced walks (ranging from 15 to 30 miles) fasted without BG rises. Weights when fasting do cause a rise, but not excessively over what might be caused by dawn phenomenon anyway.

And for me the positive health benefits - mental and physical - of exercising far outweigh any temporary BG rises.
 
Tophat1900 said:
If you exercise while fasted or after an over night fast, then there is no food there to provide the energy when it is suddenly required, so your liver will release glucose to keep your system running as it should. A lot of people find that their level rises as soon as their feet hit the floor first thing in the morning, so exercising on top of that can make the spike even great. Personally, I don't exercise on an empty stomach.
Click to expand...

This makes sense to me. I really need to learn more about intermittent fasting though, as I thought it was a case of low food intake = low levels. Obviously not. What do you eat before exercising?
 
Goonergal said:
For me the type of exercise matters in terms of spiking and as I’ve got fitter the spikes have reduced. Weights always push levels up. Less so at the end of the day than the start, but up they go. Similarly playing walking football (more energetic than it sounds) or football involving some running, or doing a long, very fast paced walk, will push levels up. However, there is always a corresponding reduction in BG levels a couple of hours later and over time, my overall BG levels go down a notch as exercise increases and becomes part of my daily routine.

Swimming, Pilates and moderate to slow paced walking all reliably bring BG down.

I regularly exercise fasted - have completed several long, moderately paced walks (ranging from 15 to 30 miles) fasted without BG rises. Weights when fasting do cause a rise, but not excessively over what might be caused by dawn phenomenon anyway.

And for me the positive health benefits - mental and physical - of exercising far outweigh any temporary BG rises.
Click to expand...

Thank you for this reply. I found Body Pump and circuit training kept me in the 5s after, but the cycling really pushes it up. Amazing how one condition affects people so differently.
 
I remember my DN talking to me about this. Obviously every individual needs to find their own threshold but she said the following;
1. If you are exercising for up to 40 minutes at a medium pace - your levels will probably not rise much.
2. If you exercise at a fast pace for less than that time, your levels will rise more.
3. If you exercise at a medium pace for over 40 mins, then expect the rise.

Simply put, keep it under 40 minutes at a steady pace and you might find you're ok! I don't know if it works like that for 'normal' people or for all types of diabetes but I experimented myself and she was spot on.
 
CherryAA said:
one way to bring down a high spike after exercise is a cold shower ( I swim in a cold pool) that seems to work for me quite reliably.
Click to expand...
I read this and dismissed it as there is no way I am taking a cold shower or swimming in a cold pool. (I put a lot of effort into trying to keep my hands and feet warm, as I have impaired circulation.) However, after reading your post I went out for a run, raising my HR more than usual, then stupidly sat in front of the computer for ages without putting on any warm clothes. I finally roused myself, thoroughly chilled, then tested my bg prior to eating. I was braced for a reading in the low 6s, as my bg tends to go up after exercise AND always goes up from the late afternoon on whatever I do. I was amazed to see 4.8, a number I only see about once in 2 months. Was it the chilling, or was it coincidence? Anyway, thanks for the tip!
 
Alexandra100 said:
I read this and dismissed it as there is no way I am taking a cold shower or swimming in a cold pool. (I put a lot of effort into trying to keep my hands and feet warm, as I have impaired circulation.) However, after reading your post I went out for a run, raising my HR more than usual, then stupidly sat in front of the computer for ages without putting on any warm clothes. I finally roused myself, thoroughly chilled, then tested my bg prior to eating. I was braced for a reading in the low 6s, as my bg tends to go up after exercise AND always goes up from the late afternoon on whatever I do. I was amazed to see 4.8, a number I only see about once in 2 months. Was it the chilling, or was it coincidence? Anyway, thanks for the tip!
Click to expand...

Interesting! I know if I get overheated I can get higher readings, so perhaps this is a weird fact that works? I’m going to try it and see. Brrrr!
 
KK123 said:
I remember my DN talking to me about this. Obviously every individual needs to find their own threshold but she said the following;
1. If you are exercising for up to 40 minutes at a medium pace - your levels will probably not rise much.
2. If you exercise at a fast pace for less than that time, your levels will rise more.
3. If you exercise at a medium pace for over 40 mins, then expect the rise.

Simply put, keep it under 40 minutes at a steady pace and you might find you're ok! I don't know if it works like that for 'normal' people or for all types of diabetes but I experimented myself and she was spot on.
Click to expand...

This is very precise, I will experiment with this and see what happens. Good to know, thank you! Anything is worth a try.
 
I always have a small bite to eat before the gym. However I must say the fitter I'm getting the less I'm getting the spikes.

I used to spike to 8 or 9 after a heavy session, now I'm in the high 6s
 
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