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LCHF pushes my BS up when exercising

cz_dave

cz_dave

Well-Known Member
Messages
450
Type of diabetes
Type 1
Treatment type
Insulin
I have been on LCHF for about 4 weeks now. I have noticed that my BS go up during pretty much any exercise - aerobic as well as anaerobic. I went jogging today and my BS would go up by 1 mmol in just 10 mins of running.

When I went to play badminton the other day, my BS just surged and even kicked me out of ketosis.

In my pre-LCHF life, my BS would go down during exercise, not up.

It looks like I will have to bolus before exercise and that could end up really tricky as my BS could drop too fast during some intense activity.

So, I have two questions:
1. How not to be kicked out of ketosis during exercise
2. How to manage BS during an intense exercise such as badminton.

Any advice much appreciated.
 
Use a small bolus initially and watch it carefully, I guess.

Have you read Phinney and Volek? They might have something to say about what's going on here.
 
Thanks, I have read 2 books by Phinney and Volek, really helpful in many ways but could not find a direct answer to my situation.

However, here is an update. I have just come back home from my Sunday badminton game(s). This time I took a bolus (just 1 unit NovoRapid) and let it peak before the game started.

My BS:
4.7 - before bolus
4.1 - bolus peak, 30 mins before playing
4.6 - 5 mins before game
5.4 - 10 mins into the game
7.2 - 30 mins into the game - here I discontinued because I did not want to get again to 11 like last week.

Next time, I will bolus again but try to let it peak in the middle of the game that lasts 60 mins.

I still cannot believe what is happening here - badminton is like a meal of pasta for me now :(
 
I must admit I am having trouble getting my head around it too. But your approach seems to be working so keep at it.
 
When does it start coming down again Dave?

Mine goes wild for 20 mins or so, then comes down. So the high doesn't last long. I still sometimes take a half unit first.
 
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Hi czDave, I get a rise in blood sugars when I do hiit stuff and a low for steady stuff. Very scientific I know.
I went on the animas sports weekend last year and a consultant said something along the lines of all legs will lower, arms and legs will raise.
Now that you are doing lchf is it that your liver is helping out by dumping sugar? Badminton is arms and legs, if I did it my body would treat it like hiit and I'd get a rise of 3-4 points from my liver joining in.
I have to up my basal 30 minutes before hand and for roughly an hour after. Then the muscles do that fantastic snatch back without needing insulin. Amazing and a pain.
 
@cz_dave, what your will be seeing is a liver dump due to a lack of glycogen in your system. To truly get into ketosis you have to blast glycogen from your muscles. Your liver can and does still produce and store it though.

Certain forms of exercise, when you are pushed anaerobic, require you to use glycogen to power your muscles. Badminton is very likely to do this, as is any form of fast running (slower endurance style is less likely to).

It's less a case of "legs and arms" I find, rather aerobic and anaerobic. A very high Intensity legs weights session also pushed my blood glucose up due to a glycogen dump. As Mrs Vimes says, you should see it as a temporary dump, as the glut4 transporters in your muscles, which are activated when exercising, should be moving the glucose out of your blood and into your muscles.
 
Thanks so much everyone for the insightful comments.

So, my understanding is the following based on your input: The glycogen stores in my muscles are rather depleted thanks to the ketogenic diet and so when doing an anaerobic exercise, my muscles badly request glycogen. The liver comes to help and dumps glucose into the bloodstream. Since I am T1, my pancreas does not counteract by providing insulin and so the muscles cannot effectively process the glucose and request more of it, the pancrease keeps dumping even more and my BS goes high. The only solution to this is to bolus before the game or switch to an aerobic sports activity.

Ok, so if I bolus and play badminton, my blood sugar should not go too high but I still wonder if I could be kicked out of ketosis due to all that glucose in my blood stream. Any thoughts? My guess is that I may be kicked out of ketosis but then perhaps the ketosis should come back again quickly thanks to the massive glycogen depletion. (see below)

And, by the way, here is an interesting account of what happened the first time I played badminton when in ketosis (about 3 weeks ago):
- I did not take any bolus with my low carb dinner and I also skipped my basal as the badminton game finishes at 10pm and I could potentially go low at night (my basal is still quite low, between 4 and 6 units of Levemir, so I can do this).
- But instead of going low, I went quite high - from around 5 to 11 during the game. I could not believe the meter as this was an absolutely new development for me. In my pre-LCHF period, I would have to eat a banana before the game and then drink apple juice during the game not to go too low.
- Equally interesting was what happened after the game. My ketones dropped to 0.4 immediately after the game but the next morning spiked to over 7! My BS went very low, I woke up with 3.9. I had to stop taking any bolus and basal for full 6 days after the game in order not to go too low. My fasting BS was consistently at 3.9, post-prandial around 5 and most of the day I was at 4.7. I am sure this was because of the total depletion of glycogen. My ketones returned to around 2 after about 3 days.
 
Tim2000s you haven't seen me play badminton mate! I look like a fairy elephant on steroids! And I never hit the b@@@@y shuttlecock. I'm much too slow. CzDave Tim has given you the proper scientific explanation there, it's all good.
Have you seen the new John Lewis advert with the little girl? That is my approach to training/sport! I'm a bit of a cart horse.
Good luck with the training!
 
Had a personal training session at 8am. 6.7 at the start. (Reduced basal for half an hour before because activities vary from week to week). Hit 7 half way through, took 1 unit correction straight away. 7.5 at end of session. No correction as driving home. 1 hour after session 7.3. 1 and a half hours after session 6 which included being unhooked from pump for 15 minutes. SNATCH BACK - love it.
Last weeks pt session I did in the low 4s. Constantly testing and drinking lucozade. It was a cardio session (shush - women's hormones and stuff as well)
 
@cz_dave, it is very dependent on the individual. Some people find that the glut4 activation in the muscles causes the sudden Bg spike to drop back (snatch back as aptly named by @Mrs Vimes) however some don't. The effects following exercise seem to differ for different people. For me, a proper hard workout that causes significant bg spikes also causes muscle inflammation and I become less insulin sensitive for 36 hours post training. The aggregate effect of the training is to make you more insulin sensitive though. I've never heard of anyone getting the reaction you had which suggests you are still producing your own insulin to some extent (even though a very small extent).
 
tim2000s said:
@cz_dave I've never heard of anyone getting the reaction you had which suggests you are still producing your own insulin to some extent (even though a very small extent).
Click to expand...

When I got my C-peptide tested back in March, it was in the normal range. So, I certainly have some insulin. It is just not able to compensate carb-loaded meals. But it can still compensate to an extent the glucose that my liver produces under normal circumstances (not when playing badminton, clearly).

So, while I am still in honeymoon, the combination of low-carb diet and sports activity has some interesting effects :)
 
The high fat in LCHF pushes up your "carb sensitivity", meaning you need more insulin to handle the same carbs. Including the carbs from your own glycogen I suppose.

Finally found a way to make sense of your experience! :-)
 
I just got back from my Sunday badminton game. This time I bolused 30 minutes before the game and it worked out quite well. I started at 5.6, 30 minutes into the game I peaked at 6.8 and at the end of the game I went down a bit fast to 4.7, so I corrected with a sip of apple juice. Now I am at 4.5 and will probably have another sip of apple juice before going to bed.
 
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