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The day after heavy exercise - different BG response?

LittleGreyCat

Well-Known Member
Retired Moderator
I'm getting back into cycling and also into low carb eating.
Yesterday was a group ride of just over 18 miles, with the usual BG spike soon after the start, and i was having to push hard to keep up with the ride even though they were going gently.
By the end I was reduced to granny gears and puffing like a steam train.
No reserves left.

Today, however, my BG has been nice and flat and within range on my Libre 2 (no DP) so I tried a little experiment.
I have been well off the wagon and have half an Aldi fruit cake in play.
This evening I had a big slice microwaved with butter, cream and a drop of brandy.
Came out just like Xmas pud.
Yum.

However this hasn't increased my BG at all.
I am now wondering if I've burned off all my glucose store and my liver is pinching any new glucose on the way in.
Or if I've temporarily decreased my Insulin Resistance so that my limited insulin production is working more effectively.

Does anyone else (T2, Metformin, Aloglyptin or similar) get a free day after heavy exercise?

I've seen something like this in the past which has lead me astray into thinking that I can have a few nice carbohydrates every now and then....
 
Can't comment on the blood sugar levels, but I find I'm hungrier than usual for a couple of days after a big hill walk. The last one wasn't a huge distance but it was very cold - I wasn't sweating - and the previous one was over 12 miles.
 
I don't have type 2 and will never have a "free day".
However, I have found the best way to limit DP is intensive exercise the day before. Or, fore, the "best" way to increase DP is to lay off exercise.

I have been fighting a cold for the last week so missed my usual gym sessions, spin classes and night on the climbing wall. As a result, my DP has been far greater than usual.
 
I am now wondering if I've burned off all my glucose store and my liver is pinching any new glucose on the way in.
Yes I think that's it. I haven't yet fully resolved my fatty liver. I find that my DP the morning after exercise is greater as I guess my liver is taking the chance to try to slim down a bit more.
So those with fatty liver are likely to get a higher than normal liver dump (which is actually a good thing long term if it helps the liver to recover).
 
More or less back to normal this morning (although DP spike not as high).
I assume my liver is now recharged.
Now to resist the temptation to just check in case.
 
I’m not type 2
If I’m going to be lifting heavy or a long bike ride I have eggs on a small slice of wholemeal toast & butter before & a protein shake with unsweetened almond milk straight after,
 
Noting that I now can't handle a baked potato so back to pre-ride state.
Interesting, though, that the effect of a strenuous bike ride can taper off over several days.
 
I'm getting back into cycling and also into low carb eating.
Yesterday was a group ride of just over 18 miles, with the usual BG spike soon after the start, and i was having to push hard to keep up with the ride even though they were going gently.
By the end I was reduced to granny gears and puffing like a steam train.
No reserves left.

Today, however, my BG has been nice and flat and within range on my Libre 2 (no DP) so I tried a little experiment.
I have been well off the wagon and have half an Aldi fruit cake in play.
This evening I had a big slice microwaved with butter, cream and a drop of brandy.
Came out just like Xmas pud.
Yum.

However this hasn't increased my BG at all.
I am now wondering if I've burned off all my glucose store and my liver is pinching any new glucose on the way in.
Or if I've temporarily decreased my Insulin Resistance so that my limited insulin production is working more effectively.

Does anyone else (T2, Metformin, Aloglyptin or similar) get a free day after heavy exercise?

I've seen something like this in the past which has lead me astray into thinking that I can have a few nice carbohydrates every now and then....
I do 2 hours intense most days in the gym, rowing machine 5k and high wattage biking, basically up hill..an hour later my bg is invariably 4.5/ 5.5 .the following morning is still low so I can eat almost anything I want and still never go over 9 bg..then start the process again.. not taking Metformin now... before this regime my bg was very erratic sometimes as high as 18 so it definitely works for me.i have finally found a regime that works for me after 23 years diabetic...
 
T2 here, I went on a big blood sugar reducing challenge early last year to try and stop the ever increasing rise in my blood sugars. They just kept very slowly ticking upwards. I was not over weight, but I was at the top end of normal. So I lost 35 lbs by exercising and being on a low carb diet (35 grams per day). I’m now bumping along the bottom of normal weight for my height.

I have been exercising daily with purpose since May 2023. I have a brisk 6 mile walk every day with my dogs. Every Monday and Wednesday I do an heart exploding mountain climb . With an elevation gain of around 700 meters it sends my heart up into the cardio zone whilst hiking to the summit and down into fat burn while descending. It’s a good 4 hour strenuous hike.

I have noted that on my two weekly mountain climbs it does have an effect on my early morning fasting sugars. They dip to around 5.4 mmol\Ls. The dip is limited and temporary and goes back up the following day to between 6-7 mmol\Ls.
 
T2 here on metformin and januvia. I’m well into my cycling after taking it up 5/6 years ago. I’ve not been out though since September as I’m currently having difficulties with my breathing.

I’m interested to hear what snacks anyone would take on 2+ hour rides? I’ve always taken things like malt loaf, fig rolls and energy bars/gels but the last ride I did my BS raised to 26 mmol/L and I ended up in hospital after collapsing so when I next go out riding I’d be looking at possible alternatives
 
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