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Rising BG after exercise, how long until this stops?

M

Muddling Through

Active Member
Messages
26
Location
England
Type of diabetes
Prediabetes
Treatment type
Diet only
I realise the thread title is a bit how long is a peice of string, but I'm curious to hear from other members.
I've lived a pretty sedantry lifestyle, I'm in the obese range for BMI (down 1 and half stone so far since early July) but I've been taking my BG's for a while now and after this mornings session on the rowing machine it raised to 7.8!


From googling though I can see this is a common occurance for some people but that it does drop off eventually to the point with after exercise your BG will drop to what it was before.

I've been fasting since last night from 7pm, and even this morning 1 hour after my last test (which I took as soon as I finished) it has dropped down again to 6.7. I seem to floating around the 6 range frustratingly despite eating fairly low carb, but I imagine that will drop in time. I hope.

So, did anyone else have this happen to them? When did your BG start to drop off instead of increase after exercise?
 
It is quite common for intense exercise to raise levels, especially if you have fasted and not eaten before working out. There just simply isn't fuel in your tank to meet the demand, so the liver will provide the needed glucose to get you through it. Think fight or flight response at work. This is perfectly normal.

Congrats on the weightloss and floating around 6 really isn't a bad thing.
 
I’ve been exercising crazy hard, my blood sugars get pretty high into the 8s & 9s then drop back to normal within an hour or so. I’ve found I can pretty much eat anything I want within that golden hour. So far I’ve tested a half a bowl of rice and a half a bowl of corn, and I still drop into the mid 4s. Tuesday is my daughter’s birthday, I plan to crush out some sprints, then help her suck down her birthday cake lol!!

I’ll report my findings lol!
 
Muddling Through said:
I realise the thread title is a bit how long is a peice of string,
Click to expand...
I think i'ts just that, as you have hinted at it, depends on your metabolism and fitness rate both will rates will change as you exercise more and get fitter.

Exercise uses up the stored sugar in the muscles, forcing the liver to break down fat and generate sugar to replenish the muscles.
Think of it like this ....

You are filling up the car, after the tank runs down.
You don't care about the amount of petrol as it passes through hose pipe.
 
In Response said:
I carried a bag of shopping uphill on a wet, windy day and my blood sugars went up.
Click to expand...
I do this regularly and my bg almost always goes up in response, but not always. I have seen it suggested that if one's bg rises after exercise one should continue the exercise longer and it will go down again. So far I have not been able to bring myself to do this so I have no idea if it would work.
 
Measure about one hour after exercise. Mine takes about 30-40 minutes . Now I try to consistently test at one hour, just for my notes
 
LaoDan said:
I’ve found I can pretty much eat anything I want within that golden hour.
Click to expand...
Sorry man not to be a kill joy or that guy...
IF your body is breaking down body fat to generate the glucose needed to replenish and repair your muscles after a work out, eating during that "golden hour" has a reverse effect.

To stick with the gas tank analogy...
you're gas tank is running dry and you have 2 full gas cans you have in the trunk, instead of using them you stop at a gas station and top up from there..

You are still driving around with the excess gas cans in the trunk..
 

You’re absolutely correct, there’s no need to eat carbs after a heavy workout. There’s a lot of bro science out there stating you need to have carbs in order for cells to absorb the necessary amino acids to rebuild muscle, it’s simply not true.

I don’t think fat repairs muscle though, aminos do. So, I should eat protein or I won’t build muscle optimally. And that’s my goal, to get jacked. I’m experimenting on myself on how to feed my muscles optimally while GLUT-4 is active. A nice 8oz ribeye, veggies and a tiny bit of carbs seems to work very well. I hover around 4.5 - 5 until the next morning, as long as don’t screw up dinner lol
 
LaoDan said:
I don’t think fat repairs muscle though
Click to expand...
Of course it does, gluconeogenesis
You liver has a store of fat at any given time it release this as glucose for your muscles to store as glycogen or speeds up the amino's ability to repair micro damage. (can remember of the top of my head I thinks it acts as a catalyst)

You want to get jacked, can't do that if your muscles are covered in a layer of fat.
If you are already at that level through your exercise then groovy.

If not remember Glut-4 is contained in the adipose tissue broken down during gluconeogenesis.
 
Please can we stick to the topic raised by the OP.

The detailed discussion about gluconeogenesis and associated issues, while interesting, should be in its own thread or via PM.

Thanks.

For what it’s worth @Muddling Through the type and intensity of exercise definitely has a bearing on what happens to my short term blood glucose levels. So vigorous walking/sports/lifting weights tend to push it up whereas a gentle saunter, swimming or Pilates brings it down. However it all has a positive effect long-term and not just on numbers - mental health and general wellbeing are so much better when being active.
 
Newly diagnosed T2 and interested in this thread too. I row in the mornings and find it does increase blood sugars. But finding the gas tank analogy makes sense so while they have gone up, it will go into my muscles to replace the fuel i’ve used. Ie i shouldnt worry about it. Husband has bought me a shiny road bike so i can dip my toe in the world of cycling, i note someone said its really effective at lowering their blood sugar. God i hope so! On a total mission at the moment! To get it down!
 
This is what my day looks like, wake up at 5:30, then a 30 minute walk, a quick breakfast, walk and ride the subway to the gym by 8:30 until 11:00.

looks like my fat tank is having a hard time keeping up. I don’t think I’m in ketosis because I’m about 1:1 ratio of fat and protein.
 

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6 is a good number to be at, and huge congrats on loosing weight. Rowing will raise you, it’s intense. But the thing to remember is you drop back down.
Walking lowers me nice and gradually most of the time, hiit will raise me, gardening lowers me fast after an hour...yourll notice what works for you. Whether it goes up or down depends on the type of exercise.
 
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