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d333gs

Well-known member
Joined
Feb 20, 2018
Messages
270
Location
France
I wobble between pre-diabetic and diabetes 2. As a result, I often monitor my blood sugar levels. Up to the last couple of weeks my blood sugar levels were down around 8 after my intense bike rides. As the temperatures have been rising here my post-ride glucose levels also started to rise. Showing levels of 14, I thought my test strips had spoiled from the heat and I opened a new batch and kept them in the fridge: Still, my sugar levels were significantly higher after the ride than before the ride. I started checking around and apparently, intense exercise can induce the release of stress hormones which triggers the liver to release glucose. This is ok occasionally, few times a year, but not 4 or 5 times a week which is my case. Not only for sugar but because you don't want elevated stress hormones. So I am backing off the intensity levels in this heat and pay close attention to my sugar levels. It will make an interesting experiment to find where my optimal level is.
 
Interesting! Do you test right after you finish your ride? Do you eat or drink anything before or after riding?

I have cycled for over 20 years, and daily on my indoor bike for the two years leading up to my surgery last month. I hadn't really considered the impact on my blood sugar.

I had my labs done about four weeks ago and my A1C was 5.0. If I get clearance to begin riding again I want to see the impact on my blood sugar after rides, dependent on their intensity. I think I'll invest in a home testing monitor and take a look at this. I may have a different baseline than you before surgery but I'd like to see the impact on me after surgery.
 
Hi

firstly (metabolically) I can't see how this is related to surgery or your exersize, unless you are saying that number is low. Because because in Australia we use mmol/L and if you mean that then "damn" that's high

showing levels of 14, I thought my test strips had spoiled from the heat and I opened a new batch and kept

so just wondering what unit system this is in because I only know of:
  • mmol/L
  • mg/decilitre
  • typo
So I'd ask @Chuck C if he can see anything exersize related here ... to me its you must have eaten something with a higher carb content before. I have seen (on fasting) that my levels of (say) 4.9mmol/L go to 5.4 after 2 hours or yard work (so my body stripped something for its required blood glucose).

Also be wary of how you handle things in and out of the fridge if there is high humidity. You will also risk spoiling a strip due to percipitation (dew) formation on the strips (or more specifically on the chemistry inside the strip) when you pop the lid if you haven't let the meach ambient before popping the lid.
Read the container for its temperature range guidance and trust that they have a few degrees either side of this with no harm
IMG20220605064328.jpg


so you would not expect these to alter if stored at 30C which I would expect is not common inside your house nor if there was a brief period of 35C.

they build that in because they know people often haven't got a good idea of what temperature it was where they stored them.
 
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Thanks for sharing your experience with elevated blood glucose. Good for you for monitoring your glucose level with a home meter. It is remarkable to me how many people on the pre-diabetes- diabetes spectrum do not monitor their blood glucose. Very important to avoid those spikes as much as possible.

I'll assume that your units are in mmol/L. Those readings seem high- especially if you are getting readings of 14 mmol/L. That is actually in the full-blown diabetes range.

Exercise can be tricky with pre-diabetes/diabetes. You definitely want to exercise regularly, as it increases your insulin sensitivity and in the big picture helps control blood glucose. In fact, regular exercise is one of the most important things that a person with insulin resistance can do to improve and control the situation. On the other hand, as you are seeing, for some individuals, intense exercise can cause blood glucose to rise for a period of time following the exercise. Your levels are probably doing fine during the exercise itself, as you’re burning up the blood glucose with your activity. However, you are correct that with intense exercise hormones are released which cause the liver to produce glucose and this can continue for some time after exercise cessation. For normal individuals with healthy insulin production, this is no problem, as their pancreatic beta cells kick out plenty of insulin to control the blood glucose being produced. But those on the diabetic spectrum generaly have significantly impaired ability to produce insulin, so there is very little to control the rise in glucose and, of course, the further someone is down the spectrum, the more impaired and the higher the glucose spike and the longer it will typically remain elevated. This can cause significant damage in all kinds of areas.

I think that you are wise to back off the level of intensity of your work outs. Something which you may want to experiment with is on the days that you train hard try adding a long cool down period at the end of your workout. Continue to bike, but just at a gentle constant pace. The idea is that the exercise should continue to burn off the glucose and keep it controlled, giving the glucose stimulating hormones time to burn off as well. If you bike for an hour intensely, maybe try an hour of cool down before stopping?

Ideally, maybe you can get your doctor to prescribe a continuous glucose monitor that you wear for a couple of weeks so that you can see what your glucose levels are doing during the entire work out and cool down period.

I think there is generally sound guidance here: Exercise Can Raise Blood Glucose (Blood Sugar) | ADA.

Please keep us posted on how your modifications affect your levels.
 
Hi jmb
yup ,I test when I get back before any post-ride snack. About 10 minutes before I start the 28k ride I have half a banana which keeps any hypoglycemic episodes at bay. I was testing about every second ride. My BS tests were usually in the low 8s. In terms of biking performance, it would go in 'good day /bad day cycles' usually ending in a better time. I switched to a tougher bike which took more effort. Then the heat hit along with the unexpected blood readings. Yesterday was the 3rd high reading after which I did some Googling.
I will back off for a few days , go back to the old bike and an abbreviated ride and start my testing.
The home test is well worth investing in. I use this ;
How to test your blood sugar
It has been very useful!
 
Thanks for sharing your experience with elevated blood glucose. Good for you for monitoring your glucose level with a home meter. It is remarkable to me how many people on the pre-diabetes- diabetes spectrum do not monitor their blood glucose. Very important to avoid those spikes as much as possible.

I'll assume that your units are in mmol/L. Those readings seem high- especially if you are getting readings of 14 mmol/L. That is actually in the full-blown diabetes range.

Exercise can be tricky with pre-diabetes/diabetes. You definitely want to exercise regularly, as it increases your insulin sensitivity and in the big picture helps control blood glucose. In fact, regular exercise is one of the most important things that a person with insulin resistance can do to improve and control the situation. On the other hand, as you are seeing, for some individuals, intense exercise can cause blood glucose to rise for a period of time following the exercise. Your levels are probably doing fine during the exercise itself, as you’re burning up the blood glucose with your activity. However, you are correct that with intense exercise hormones are released which cause the liver to produce glucose and this can continue for some time after exercise cessation. For normal individuals with healthy insulin production, this is no problem, as their pancreatic beta cells kick out plenty of insulin to control the blood glucose being produced. But those on the diabetic spectrum generaly have significantly impaired ability to produce insulin, so there is very little to control the rise in glucose and, of course, the further someone is down the spectrum, the more impaired and the higher the glucose spike and the longer it will typically remain elevated. This can cause significant damage in all kinds of areas.

I think that you are wise to back off the level of intensity of your work outs. Something which you may want to experiment with is on the days that you train hard try adding a long cool down period at the end of your workout. Continue to bike, but just at a gentle constant pace. The idea is that the exercise should continue to burn off the glucose and keep it controlled, giving the glucose stimulating hormones time to burn off as well. If you bike for an hour intensely, maybe try an hour of cool down before stopping?

Ideally, maybe you can get your doctor to prescribe a continuous glucose monitor that you wear for a couple of weeks so that you can see what your glucose levels are doing during the entire work out and cool down period.

I think there is generally sound guidance here: Exercise Can Raise Blood Glucose (Blood Sugar) | ADA.

Please keep us posted on how your modifications affect your levels.
Thanks Chuck!
" Something which you may want to experiment with is on the days that you train hard try adding a long cool down period at the end of your workout. " great idea, I will do that. I think I have reached my peak time and I will back off trying to beat the clock. Doing blood tests during the ride is easy, I will try that too.
 
Hi

firstly (metabolically) I can't see how this is related to surgery or your exersize, unless you are saying that number is low. Because because in Australia we use mmol/L and if you mean that then "damn" that's high



so just wondering what unit system this is in because I only know of:
  • mmol/L
  • mg/decilitre
  • typo
So I'd ask @Chuck C if he can see anything exersize related here ... to me its you must have eaten something with a higher carb content before. I have seen (on fasting) that my levels of (say) 4.9mmol/L go to 5.4 after 2 hours or yard work (so my body stripped something for its required blood glucose).

Also be wary of how you handle things in and out of the fridge if there is high humidity. You will also risk spoiling a strip due to percipitation (dew) formation on the strips (or more specifically on the chemistry inside the strip) when you pop the lid if you haven't let the meach ambient before popping the lid.
Read the container for its temperature range guidance and trust that they have a few degrees either side of this with no harm
View attachment 888570

so you would not expect these to alter if stored at 30C which I would expect is not common inside your house nor if there was a brief period of 35C.

they build that in because they know people often haven't got a good idea of what temperature it was where they stored them.
Hi Pell
Yes we are seeing high 30s here in the South of France. I live in a loft with no AC. I have had strips go off before and thats what I thought was happening again . Besides not liking the sugar levels , the activation of the stress hormones indicated that I was over-exerting , pushing too hard, which I expect is not good for my freshly rebuilt heart .
Of interest re over exercising;Why you may need to exercise less: learn about your cortisol levels
 
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Hi Pell
Yes we are seeing high 30s here in the South of France.
well that surprised me ... still I've only been to one part of southern France and that was Ax les Therms

thanks for that data :)

I have only minor knowledge on the aspects of blood glucose and exertion, but what little I know was surprised by such a rise. For instance when fasting two hours of yard work has driving my BG up from 4.9 to 5.2 (or something) but I wasn't high intensity training by any means.

Best Wishes
 
Hi
I'm still gnawing on this because
  • it interests me
  • its a subject here with a claim and not much data
Reading through the presented theory for the how I don't see quantification of levels only qualitative view of "it can rise" .. to me rising from "normal" to 14 is very interesting and I'm not sure I can understand the body doing that without significant failures of mechanism.

So, if you don't mind I have a couple of questions

Still, my sugar levels were significantly higher after the ride than before the ride. I started checking around and apparently, intense exercise can induce the release of stress hormones which triggers the liver to release glucose

what was your blood glucose level before the ride (should be still in the machines memory at this early stage)?

what did you drink and or eat before and during the ride, as I said above:
... to me its you must have eaten something with a higher carb content before. I have seen (on fasting) that my levels of (say) 4.9mmol/L go to 5.4 after 2 hours or yard work (so my body stripped something for its required blood glucose).

It would be very worthy of attention if you went from 8 to 14 during a ride.

Did you hydrate during the ride? It was a long ride, was it pure water or a sports drink? Was there any glucose in that?

What did you drink or eat upon return before checking blood?

Its a very interesting question but its hard to accept the results (as you yourself were concerned about the strips) without knowing what you ate and drank between the pre ride glucose check and the time you checked glucose again after the ride.

I've become interested in this topic over the last few months after discussions with Chuck and Leadville about possibilities of my own insulin resistance (answered by buying a machine and investigating). As it happens (happily) my own situation is pretty decent. (5.6 or under after waking ...)

Thanks
 
Pre ride could be around 12 depending on what I ate for lunch.When I start the ride I dont stop till I get home , no pauses for water. The exercise with the bike usually reduces my sugar down to the 8s. BUT , as I have just discovered, if you start overexerting, stress hormones kick in and trigger the liver to release glucose therefore raising sugar levels rather than lowering them . This is alright occasionally but not consistently as is happening to me. I have been pushing too hard so I will back off.

Per the earlier post to jmb
"
,I test when I get back before any post-ride snack. About 10 minutes before I start the 28k ride I have half a banana which keeps any hypoglycemic episodes at bay. I was testing about every second ride. My BS tests were usually in the low 8s. In terms of biking performance, it would go in 'good day /bad day cycles' usually ending in a better time. I switched to a tougher bike which took more effort. Then the heat hit along with the unexpected blood readings. Yesterday was the 3rd high reading after which I did some Googling.
I will back off for a few days , go back to the old bike and an abbreviated ride and start my testing. "
 
Hi @d333gs - I was diagnosed with diabetes fifteen years ago, I got it into complete remission about four years ago and the diagnosis has been removed from my medical record. I note you say about your blood glucose levels:
Pre ride could be around 12 depending on what I ate for lunch....<snip>....About 10 minutes before I start the 28k ride I have half a banana which keeps any hypoglycemic episodes at bay....<snip...I was testing about every second ride. My BS tests were usually in the low 8s

Those levels are high. What do you eat that gives you levels of 12 and low 8s ? And what do you mean by hypoglycemic episodes - how low do your BS levels get ? Eating half a banana will certainly raise BS rapidly.

Without knowing what you mean by hypoglycemic episodes, it sounds like you might be swinging between highs and lows possibly due to the foods you're eating ? Be good to know what you normally eat.
 
About 10 minutes before I start the 28k ride I have half a banana which keeps any hypoglycemic episodes at bay

Like Paleowoman, I'm wondering about the banana and what you mean by hypoglycemic episodes? Are you on insulin? If on insulin, then hypos could be an issue and there is a bit of a balancing act. If your not on insulin, I doubt that you're going to have issues with hypos from exercise. Hypos are a big issue for type 1 diabetics who exercise, because they are on insulin, as type 1s don't produce insulin and must inject it. They also have issues with hyperglycemia after exercise, probably for the same reason that you are, and often have to inject insulin after strenuous exercise. Type IIs, if on insulin, have the same concern about hypos. But, typically there would not be issues with hypos during exercise if not on insulin for type IIs.

As with checking INR, it does come down to 'knowing thyself" and by testing like you do, I imagine that you know yourself well by now. Are you getting below 4 mmmol/L when you exercise if you don't eat a snack? If you are coming down to 5 or 6, that should not be an issue of concern and would not be considered hypo.

It is possible that the banana could be putting your BG on a bit of a roller coaster ride. You indicated that you plan to test during your ride and after. You might also experiment with skipping the banana, and checking to see if you are truly getting hypos. You could always keep it handy just in case.
 
Like Paleowoman, I'm wondering about the banana and what you mean by hypoglycemic episodes? Are you on insulin? If on insulin, then hypos could be an issue and there is a bit of a balancing act. If your not on insulin, I doubt that you're going to have issues with hypos from exercise. Hypos are a big issue for type 1 diabetics who exercise, because they are on insulin, as type 1s don't produce insulin and must inject it. They also have issues with hyperglycemia after exercise, probably for the same reason that you are, and often have to inject insulin after strenuous exercise. Type IIs, if on insulin, have the same concern about hypos. But, typically there would not be issues with hypos during exercise if not on insulin for type IIs.

As with checking INR, it does come down to 'knowing thyself" and by testing like you do, I imagine that you know yourself well by now. Are you getting below 4 mmmol/L when you exercise if you don't eat a snack? If you are coming down to 5 or 6, that should not be an issue of concern and would not be considered hypo.

It is possible that the banana could be putting your BG on a bit of a roller coaster ride. You indicated that you plan to test during your ride and after. You might also experiment with skipping the banana, and checking to see if you are truly getting hypos. You could always keep it handy just in case.
Thanks Chuck
No , If I have been eating low carb/salads I can have a hypoglycemic episode durring exercise mid afternoon.It will drop to about 7 which is uncomfortable. This is not uncomon for a D2 on an empty stomach. The banana is slow release. I rather have a banana beforhand in place of a sport drink with sugar durring my routine. I have been doing this for years. If my ride was for 2 or three hours I would be nibbling en route. My D2 is well controled and I rarely have any issues with it.
The big surprise was the rise after the ride.
 
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Hi @d333gs - I was diagnosed with diabetes fifteen years ago, I got it into complete remission about four years ago and the diagnosis has been removed from my medical record. I note you say about your blood glucose levels:


Those levels are high. What do you eat that gives you levels of 12 and low 8s ? And what do you mean by hypoglycemic episodes - how low do your BS levels get ? Eating half a banana will certainly raise BS rapidly.

Without knowing what you mean by hypoglycemic episodes, it sounds like you might be swinging between highs and lows possibly due to the foods you're eating ? Be good to know what you normally eat.
My A1c range from 6.5 to 7.5
 
My A1c range from 6.5 to 7.5

My A1c is 5.2.

Hypoglycaemia is usually defined as under 3.9. If you feel uncomfortable with a blood glucose level of 7 that will surely be because you are not used to that level and that you must be used to being on higher blood glucose levels - which means diabetes.

You haven’t told us what you usually eat. What do you mean by low carb ?

I adopted a very low carb diet soon after my diabetes diagnosis and it was because of that diet that my diabetes has gone. I still eat that way despite being non diabetic now because I like this way of eating and I eat extremely well too. I hardly ever eat salads - boring ! I eat meat, fish, eggs, cheese, cream, some nuts, non starchy low carb vegetables eg asparagus, cabbage, kale, cauliflower, courgettes, broccoli, aubergine, peppers, okra, and fats, eg butter, olive oil, coconut oil, avocado oil, which I add loads of to food for cooking - that gives me a lot of energy. I do not eat bread, rice nor any other grain foods nor foods made from them, nor any foods with sugars of any sort, nor high carb starchy vegetables eg potatoes, carrots, nor fruit.

You might find this book of interest, Diabetes Unpacked by Prof Tim Noakes and others: Diabetes Unpacked: Just Science and Sense. No Sugar Coating (English Edition) eBook : Noakes, Tim, Fung, Jason, Teicholz, Nina, Kendrick, Malcolm, Harcombe, Zoë, Cywes, Robert, Gerber, Jeff, Cummins, Ivor, Unwin, David, Zinn, Caryn: Amazon.fr: Boutique Kindle

Prof Tim Noakes has written several books on exercise and diet and has an interest in diabetes. He is emeritus professor in the Division of Exercise Science and Sports Medicine at the University of Cape Town. I copy this excerpt from Diabetes UK website about Tim Noakes: "Prof Noakes gives a brief account of how he developed a passion for running and how ended up researching in the field of exercise science. This brings him on to a paper he produced, the results of which he says could have allowed him to diagnose his insulin resistance (or type 2 diabetes) in his twenties rather than in his fifties. This paper, in which Prof Noakes was himself a subject, showed his glucose levels rose sharply with intense exercise, despite high insulin levels, on a high carbohydrate diet, whereas this response was blunted on a low carb diet. Following this and a string of other studies on carbohydrate metabolism, Prof Noakes became a world authority on the subject” (My bold)
 
My A1c is 5.2.

That's excellent, especially for someone who was previously diagnosed with diabetes.

I was diagnosed with pre-diabetes in 2019. Looking back at my previous bloodwork, it turns out that I had been pre-diabetic for at least 8 years, but no physician had ever brought it to my attention. It's really a medical blind spot, as control and reversal is much easier when a person is still in the pre-diabetic range. Medicine tends not to pay much attention until a person crosses the diabetic threshold, unfortunately, and by that point pancreatic beta cell function is typically significantly impaired.

I eat similar to you. I would describe it as a Mediterranean whole foods diet. I avoid almost all sugars and processed foods. By testing at 1 hour and 2 hours after every meal, I was able to determine which foods to avoid or limit, which tend to be starchy high carb foods which are high on the glycemic index. But, I do like my salads. I just finished off a large Mediterranean salad with wild caught Sockeye salmon. For oils I tend to favor olive oil and avocado oil.

My A1c has been 4.9% to 5.1% for the past 2 years. So, my doctor tells me that I've reversed my pre-diabetes, based on A1c and fasting blood glucose levels. But I still continue to eat this way, as I enjoy it so much. Also, the real test is the post meal blood glucose and I know that, even though I no longer technically have the diagnosis, in reality my post meal blood glucose levels will still rise to the prediabetic levels if I slip up and eat high glycemic index foods.

A book which I would recommend is Jenny Ruhl's Blood Sugar 101. Very much science based. She talks about the 5% club, which is folks who have diabetes but who aim to have their A1c under 6.0%.

https://www.amazon.com/Blood-Sugar-...4458801&sprefix=blood+sugar+10,aps,164&sr=8-1
 
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Good morning (from me here in Australia)

Pre ride could be around 12 depending

so basically you didn't measure before ... so if that's the case you can't be sure of what it was so its hard to call a spike

I'll call your attention to this article (which gives quantitative data)

https://beyondtype1.org/dehydration-blood-sugar/
  • Mild to moderate levels of dehydration—especially during hot weather, intense exercise, or illness (diarrhea or vomiting)—can easily spike your blood sugar 50 to 100 mg/dL or higher.
so I'm going to apply Occam's razor here and say that in the absence of data this theory could well be the answer not least because it entirely fits your situation as well as your reports. I think it provides an answer that's more simple and applicable to your stated situation.

I would also suggest you follow this guidance from that:

Beware that hydration fluids like Gatorade and Pedialyte can contain sugar—read the nutrition labels carefully and talk to your doctor about potentially dosing insulin with the hydration beverage or choosing the “zero sugar” or “low sugar” options.​

lastly according to what we classify things as in Australia you are past pre-diabetic and into diabetes. You should pay attention to that and react accordingly to preserve your health. You may still have some functioning in your pancreas but you are in insulin resistance territory.

Best Wishes
 
I eat similar to you. I would describe it as a Mediterranean whole foods diet. I avoid almost all sugars and processed foods. By testing at 1 hour and 2 hours after every meal, I was able to determine which foods to avoid or limit, which tend to be starchy high carb foods which are high on the glycemic index. But, I do like my salads. I just finished off a large Mediterranean salad with wild caught Sockeye salmon. For oils I tend to favor olive oil and avocado oil
I tested like you do ! And I do eat occasional salads....your sockeye salmon one sounds right up my street. I wil also eat a goat's cheese with bacon lardons salad - minus the bread which others have with that !

I was going to recommend Jenny Ruhl's Blood Sugar 101 too - you beat me to it !

I'd also recommend Diabetes Solution by Dr Richard Bernstein: Dr Bernstein's Diabetes Solution: A Complete Guide To Achieving Normal Blood Sugars, 4th Edition: Amazon.co.uk: Bernstein, Dr Richard K.: 8601400129777: Books

This was the first book I read on my diabetes diagnosis, I was pretty shocked at the time as I had been given some blood tests and my fasting blood gluocse was high, but I was slim and didn't eat much processed foods so couldn't understand it. Endocrinologist I was referred to thought it was Type 2 - there are some slim ones.

Anyway, the book: Dr Bertstein is actually a Type 1 diabetic himself but he wrote the book for all types of diabetics. The book is extreme low carb - no more thatn 30g carb per day, 10g per meal, which I was able to do. It helped show me that it's carbs that mostly raise blood glucose, though very large portions of protein can do so too. Dr Bernstein bought himself a blood glucose meter at a time when only doctors could obtain them, his wife was a doctor. He was the first patient to monitor his own blood glucose, he then retrained from being an engineer to becoming a medical doctor and then an endocrinologist and created the movement for patients to check their own blood sugars at home - he felt it critical that diabetic patients check their blood sugars before and after meals, i and 2 hours after, so that they could see what foods affected them and when - important especially for Type 1s or Type 2s on insulin as he brought in the principle of small numbers for people on insulin so that they are less likely to get hypos which can be fatal when a person is on insulin (my DH's mother was a Type 1 who died of a hypo).
 

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