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Exercising raises my blood sugar

A

ariaxo

Well-Known Member
Messages
194
Type of diabetes
Type 1
Treatment type
Other
I like to do Zumba and just dance to music as a form of exercise and my blood sugar would rise up to 16+ after I exercise. This happens ALL the time. How is exercising healthy for me when it raises my blood sugar significantly? That’s why for such a long time I didn’t exercise cause it spikes my blood sugar??? But howwww? I’m not stressed, I’m happy. And I’m not consuming sugar. Will I have to take insulin before I exercisev
 
I'm not a T1, but when you do anything strenuous, your liver starts to dump glucose to help give you energy... Which with too little insulin floating around, you can't burn off. As a T2 I'm better off with long walks, those'll drop my blood sugars every time, because it's slow and steady, doesn't make me sweat nor kick my liver into overdrive. Others here will know whether to adjust your basal for a bit or not, but that might explain the rise.
 
There are two things which happen when we exercise.
1. As @JoKalsbeek mentions, our liver dumps glucose to give us ehe energy for the exercise, A healthy pancreas would release insulin to convert that glucose. Those of us with an unhealthy pancreas cannot release the insulin appropriately.
2. Our bodies become more sensitive to the insulin. A healthy pancreas would react by switching off or lowering the insulin production. Those of us with unhealthy pancreas cannot do that and if we have injected insulin (basal or bolus) our blood sugars may lower. This is why some of us experience hypos when exercising.

We are all different and not all exercise is equal. With stop-start exercise (like HIIT or weight training) the liver dump happens when we start each set of exercise but as the set does not last long enough for the insulin sensitivity to happen. This is why some exercise can lead to higher blood sugars.

This is why, typically, longer constant exercise is more likely to reduce blood sugars.

But, of course, it is not always that easy - we have stress to consider which raises blood sugars. An extreme comparison of this would be two cycle rides of the same duration. This first is flat and fast on a warm (but not hot), dry day. This will most likely reduce blood sugars. The second cycle ride will be uphill against the wind on a cold, wet day. This could raise blood sugars.

Unless you are a very fit cyclist who does this every day, in which case, you body will not be stressed.

Before the pandemic, I was a regular visitor to the local climbing walls. Climbing is stop start and stressful (in a weird fun way) so my blood sugars would always rise. To counteract this. I would take extra insulin before I started. I would calculate my insulin dose such that it would reduce my blood sugars to 3.0 under normal conditions. As this was no normal conditions, my blood sugars would be flatter. You could try this with Zumba - but make sure you have your hypo treatment close to hand in case you over do the dose.

Finally (sorry for the long response), the liver dump I mentioned above will mean that you will have less glucose to dump for the next 24 to 48 hours. Therefore, your blood sugars could reduce after Zumba so keep a close eye on them.
 
Wow thanks for the long tesponse. Could I maybe take insulin before I exercise? Because Zumba is the only exercise I enjoy and am persistent with
 
ariaxo said:
Wow thanks for the long tesponse. Could I maybe take insulin before I exercise? Because Zumba is the only exercise I enjoy and am persistent with
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That is exactly what I did with climbing - take insulin before I started climbing which "under normal conditions" would aim for a target of about 3mmol/l. Because my climbing pushed my blood sugars up, I never reached that level but the insulin stopped them going too high. I cannot advise what doses and targets would suit you and your Zumba but I would suggest taking some insulin before your class is worth a try.
Remember, we are all different so, like everything with diabetes some trial and error is needed with your hypo treatment close by.
 
Beware of correction doses of insulin and exercise. It's a sure way to cause a drastic hypo either within the class or over the next 36 hours.
I suggest you start investigating and ask your consultant before resorting to correction doses before exercise (as fast-acting insulin plus exercise is something I am unable to do. On rare occasions, I correct after exercise with food.). What were your BS's before you started the class? Had you eaten any food before the class that wasn't covered by insulin? Had your BS returned to normal after your last meal? When did you last take fast-acting before the class? Could it be your basal is running out at this time?

Exercise always lowers blood glucose (BG) on a 24-hour basis, but sometimes exercise also briefly raises BG following a workout.
 
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My blood sugar rises when the exercising I'm performing is intense (something like an outdoor boot camp), my consultant explained that one of the reasons was the body's stress response. When I go for a cycle they tend to stay where they are drop a little, in which case I'll have some Jelly Babies.

When they raise, I was advised not to inject as it could drop fairly quickly in a few hours, the quicker the drop happens the fitter you are, apparently. Instead, I will go for a short, slow run, the body will have stopped the release from the stress response and the run will use the remainder. Seems to work for me.
 
My blood sugar was 7.7 and after an hour of exercising, it was 16.2. It’s just so sad that exercising can be dangerous for us and we have to take insulin for some exercise. It’s so unfair. Can a basal insulin stop working after some time? Maybe I have basal issues but my toujeo used to work perfectly (not with exercise) but other things. are there better insulin pens
 

Hi there, well I wouldn't say dangerous exactly, just tricky until you've found a way around it. I exercise a lot (most days) and I have worked out what happens depending on whether I am going for it or jogging along at a leisurely pace, or doing it in the morning or afternoon or for how long, etc. When your levels go high immediately after very energetic exercise, how long before they come down again? For me it's around an hour and then they go low and stay low all day, I did take an extra unit of insulin when experimenting and was fighting hypos the rest of the day. I am happy to take a hit of a high if it's for an hour or so because the benefits of exercise overall outweigh the downside of a higher glucose level temporarily. x
 
Reactions: ert
Toujeo should last up to 36 hours. Have you tested your basal by meal skipping or eating a carb-free meal to see if your dose is correct? Did you eat something before the class? That's a really big blood sugar rise you're experiencing. It's worth discussing with your DN to see if they can figure what's happening.
In sprint training, I may rise from 6 to 8 mmol/l but it crashes later. If I tried a correction dose of 1 unit during exercise I'd experience a double arrow down on my Libre, followed by a hypo.
 

I injected 5 units and after an hour, it was still 16.2. Honestly I’m starting to feel really depressed, why is my body so resistant to insulin?
You know, if my blood sugar is 26, I would have to take 20 units to bring it down whilst most people may take 5-10. It’s so difficult to keep my blood sugars normal.
 
 
I know!!! My body is so resistant to insulin, it’s so hard. No, so how do I do that? I take toujeo in the morning so which meal could I skip to test it out. No I had a banana. Also is it normal to take 4 units just for a single banana?
 
ariaxo said:
I know!!! My body is so resistant to insulin, it’s so hard. No, so how do I do that? I take toujeo in the morning so which meal could I skip to test it out. No I had a banana. Also is it normal to take 4 units just for a single banana?
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Try to drink water before the class and don't eat the banana. A banana would raise my blood sugars 3 to 4 mmol/l.
Here is how to test your basal. Make sure you speak to your DN first:
https://www.mysugr.com/en/blog/basal-rate-testing/

I really hope you get this sorted soon.
 
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ert said:
Try to drink water before the class and don't eat the banana. A banana would raise my blood sugars 3 to 4 mmol/l.
Here is how to test your basal. Make sure you speak to your DN first:
https://www.mysugr.com/en/blog/basal-rate-testing/
Click to expand...
I’m sorry I really can’t take all that information in, is there a shorter explanation
 
ert said:
What time of day is your Zumba class?
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I do home Zumba from a YouTube video and I usually do it around this time. Just did it now.
Also quick question, what is the maximum time between meals I can eat? Because I eat every 3 hours which I think is contributing to my bad blood sugar. Maybe if I less regularly, my blood sugar swill be stable because surely not eating will mean my blood sugars will be fine
 
This is quite normal - it happens to me when I go to spin, especially when I first started doing it - my bloods can be perfect all day but shoot up to 17 during the class. The more effort I put in the higher the sugars. I do a bit of a correction dose afterwards but they also tend to drop on their own after an hour or so. I tried injecting before the class once but ended up hypo so it’s maybe safer not to.
I found eating 20g slow-acting carbs ( protein bar) 40 mins before the class actually stopped it going so high.

Although there is an initial high sugar, exercising should improve overall control and insulin resistance..
In reply to your last comment, I’d say that depends if you’re on injections or pump? I can go all day without eating but I’m on a pump with tested basal rates. Can you speak to your diabetic nurse about it all?
 
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Reactions: ert
Although it's not perfect (because some anaerobic exercise is also aerobic, and vice versa), the general rule of thumb is:
  • Aerobic exercise reduces blood sugar
  • Anaerobic increases it
A 15-30 minute vigorous walk will often bring your blood sugar down after anaerobic exercise.

It might not seem like it, but dance is very anaerobic. If your muscles strain more than your lungs, it's probably anaerobic. Even seemingly aerobic exercise like cycling can involve a lot of anaerobic activity, especially when you start cycling uphill and your legs encounter a lot of resistance.

When your muscles are under strain, your liver dumps glucose into the bloodstream. But when this stops, getting your heart rate up even a tiny bit without overworking your muscles will increase your insulin sensitivity and your bolus will usually see you come back down, hence the walking.
 
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