Trying to eliminate running BG LOWs and post run BG HIGHs

I sometimes feel like napping in the middle!! Lol, not really. I try to run 6 days a week, Monday off. Sometimes I just can’t fit it in though and I really notice the missed days! :frowning: So today is an off day :slight_smile:

I don’t monitor the distance when I’m on my own but I sometimes run with a partner who is an ultra runner in training and is very meticulous about the distance. I usually run with her 10 - 15 miles on trails depending on how much she needs to add to her schedule! She wears a garmin and it beeps at every mile :wink: Often she will have already run 20 miles before we meet! She’s incredible!:star_struck:

Incredibly (and knock on wood), for the last few runs, I’ve really not had any significant post-run highs. Well, I’ve learned from your posts / experience re: ZB, etc.:slight_smile: Yes, eating post-run is tricky for me, too! I’m going to try @daisymae’s recommendation of the Boost Glucose Control Nutritional Drink. Yes, eating a banana even without a rise can be disastrous!:face_with_raised_eyebrow:


Depending on your pace, you are probably using a good mix of muscle glycogen and fat metabolism to fuel this type of run. Even if you are burning mostly fat, if you do this 6x a week, you are still using a lot of muscle glycogen.

The body will replenish muscle glycogen. But how it replenishes depends on your diet and how you re-fuel after runs.

I have seen from some of your previous posts that you are relatively low-carb. The body can replenish muscle glycogen from non-carb sources, but the process is not as fast and efficient. It’s a bit of a roundabout process.

Fat cannot be converted directly into glycogen. But fat can be turned into glucose. That process is called gluconeogenesis - the metabolic pathway where glucose is generated from non-carbohydrate sources.

So with a low-carb diet, your process is that some of the fats you eat are converted to glucose (mainly in the liver), and then that glucose is released into the blood for conversion by cells in the muscles into muscle glycogen.

When you are exercising almost daily, the body can get a bit behind on replenishing muscle glycogen. That’s why I have always recommended carbs immediately after exercise.

And your body will replenish much faster if you have the carbs very soon after workouts.


i have yet to figure out how to bolus for a banana, especially if i want to eat it with peanut butter. :tired_face: go figure.


Thank you @Eric for the analysis of the effects low carb has on running. I didn’t know this.

I’m not exactly sure of my pace since we sometimes stop for bathroom, etc. Maybe around 9 mins or so without stops. Or does stopping matter, you just need an overall time and distance from start to finish including stops? I’ll try to figure it out tomorrow if my partner is available w/ her Garmin :slight_smile:

Yes, I sort of thought you would think my carbs were too low :thinking: Well, I’m not really on a low-carb diet but I just cannot manage to control my BG whenever I eat high carbs, like pasta! It’s a night of never ending corrections!

So I bought some Glycerna at the store today (and got a parking ticket, to boot!). I could not find the Boost which @daisymae recommends. The Glycerna seems to be very similar w/ 16g carbs. I’ll try it tomorrow to see how my stomach tolerates it! Do you think that by increasing my carbs (and proteins) post-run that my overnight lows might be reduced? I think I read on your Sports Wiki that it would help to stabilize overnight BGs, too, or maybe that was just my wishful thinking :wink:

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do you wear a pump? i am guessing yes, that you do. for pasta and moderate carbs meals, have you tried changing your ICRs for the specific meal? or even doing an extended/ dual bolus?

the funny thing about carbs, at least that i have found, is that at the times i lower my carbs to accommodate for less activity, when i return to higher activity and higher carbs, it takes my body a while to sync up and i dont metabolize the carbs the same way as i did before. i have no idea of why this happens; i just know that it does. i am certain that eric will have an answer :wink:

(one other thing that i have learned is that when i am eating a carby meal, i MUST include protein with it, for example fish, chicken, turkey, eggs…)


Definitely helps when you do that. It doesn’t mean you will never have a nighttime low, but it can certainly reduce them and make them less severe than they would be if you did not refuel.


@daisymae Yes, I use OmniPod. Good suggestion re extended bolus. I’ve tried extended bolus off and on with varying success. I can’t seem to get consistent results with extended bolus on high carb meals. I usually end up using extended, plus lots of corrections.

I’m trying out an extended bolus tonight with 30g carb dinner. I was already on the low side, 70, so I took 1U immediately and another unit extended over 2 hours. So far only dropped down to 59. One hour left extended but I anticipate having to take corrections in bolus+3 or 4 hours as I often get a delayed spike:(

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by any chance, do you have diabetic gastroparesis? have you ever seen a GI specialist? i am no doctor, but i mention this b/c i had similar problems, had an endoscopy, and was diagnosed with “delayed gastric emptying.” now i take medication, and i no longer have the problem that you are having.

food for thought.

there have been some people who have shared on this sight who take their insulin AFTER eating just in order to have the insulin peak to meet their digestive peak. we’re all so different.


Yes, that has occurred to me, too, after reading about others experiences. I’ve not been checked though. I didn’t know there was medication that one could take for it. I’m sure glad it helps you. Some food for thought at my next Dr appt…:slight_smile:

Last night’s extended bolus helped, sort of. Except instead of going low, I remained a bit high, 133, for a few hours from around 9pm til I finally took a correction. Go figure :slight_smile: Yesterday was a rest day, too, so that probably had some bearing as well :slight_smile:


i take a medication called Donperidone. its not approved by the FDA so i get it from Canada. many others on FUD take it. of all the GP Ds, it has the least side effects and is the most successful.

i had this problem today as well. i dont have a clue why i stayed high. i was on the low side throughout the night (50s ), but after breakfast i spiked to 122, and then i turned off my pump so i went even higher (145) without any IOB. i swam hard, so i was curious as to why my BGs were behaving so stubbornly. at the end of my swim, and i swam for 1.5 hours, i had only come down to 115 !!! i couldnt believe it. anyway, i bolused hard once i got out of the pool, and my last BG was 98 and coming down.

i bolused 50% of the carbs for my BOOST shakes. we’ll see what happens.

Eric always tells me that its not necessarily the day off that counts, its what you did the day BEFORE that counts. but you run 6 days a week, right? i think its just that our D bodies are not always very predictable. i have no clue as to why i was so high today. just correct and move on :sunny:


Today’s run went really well, probably due to the beautiful, light snow fall coming down :slight_smile: Not too hot, and soft ground :slightly_smiling_face:

I met my ultra runner friend and per her Garmin, we ran 10.33 miles for 2 hours exactly but we stopped along the way for the bathroom and a few other places, maybe for a total of 10 minutes. I wore my trusty Sony Smartwatch which acts as the xDrip+ Dexcom transmitter collector and has a step counter. I also started the Fit app on my watch. It had quite a different result from the Garmin, with an estimate of 11.84 miles, probably not accurate!


Tidepool chart:
Shows lows during the run as low as 49, but I never felt those lows so I’m thinking Dex was just off. I did a finger stick at the end of the run, and BG was 90, whereas Dex showed 65.

And the numbers…

  • 1/2 HR pre run-start: BG 83 (Dex), Temp Basal reduced by 80% for 2 HRs: 0.5U/hr down to 0.1U/hr
  • 1/2 HR pre run- end : Resume normal Basal (0.5U/hr)
  • Run-start: 11:30 AM, BG 84 (Dex), IOB 0U
  • Run-end: 1:30 PM (with a couple of stops, so @1 hr 50 mins run), BG 65 (Dex), 90 (finger), Bolus 1.3U immediately upon end
  • Post-run: 2.15 PM drink 1 Glucerna Chocolate Shake 16g carb), chunk of parmigiano cheese
  • Post Run: 3:29 PM BG 74 (Dex) … still going up slightly.

So, immediately bolusing post-run does indeed seem to consistently prevent a post-run spike (thanks @daisymae and @Eric!) . No spike at all. 2.5 hours post-run and I’m going up a bit, BG 85 but it’s probably from the extra cheese that I ate :frowning:

This is my first try at refueling properly. I tested the nutritional shake just to be sure my stomach could tolerate it. And it did! Very chocolatey! Thank you, @daisymae, for the recommendation!! I think 16g carb is probably too little but I can’t really tell what optimal refueling is, not physically, at least not yet! But just by reading @Eric’s FUD sports wikis, it seems like I may need to increase the amount. I’ll see how tonight goes!


i am thinking like eric now: you need more fast carbs for refueling !!! that’s why i do 2 of the shakes at once. but i dont eat any cheese b/c the fat in the cheese will slow down your digestion of the fast carb replacement. also, the cheese, as you thought, is probably the culprit for the rise in your BG. also, how did you bolus for your Glucerna shake? did you bolus for 100% carbs? or less, like i do?

may i ask, what is your A1c ? i usually come in between 4.9 and 5.2 . (same with eric)

great numbers BTW !!! awesome job. keep us posted on how your evening goes with all the changes that you made today. also, do you do a lower TB overnight for a couple of hours to prevent lows?


Yes, I saw your post. Did you reduce your basal the previous day/night? That can always cause a high even a day later, at least with me.

Yes, the day BEFORE I just ran, nothing special but probably something I’m overlooking. Nothing is by accident in our bodies! There is probably some rhyme and reason for it but too intricate for ME to figure out… :frowning: Yep, tomorrows another day :sunny:


everything adds up: bad nights sleep, anxiety, frustration, guessing how many carbs are in an unfamiliar meal, and of course EXERCISE!!! :blush:


I have shared this with DM before. Think in terms of a car’s fuel tank. Imagine completely filling up with gas on Monday (for instance a rest day).

You drive a bit each day. And you also put a little bit of gas in the car each day, but not as much gas as you use.

If you do that long enough, eventually your car will run out of gas. Will it be Thursday? Friday? Saturday?

At some point, it is inevitable.

Yes, you can replenish muscle glycogen with non-carb sources, but it is slower, as I posted about a few days ago.

Whatever you burn, replenish! That will help you avoid lows.

And yes, the other thing you mentioned, my Dex can frequently be very inaccurate during long runs.


Oh, wow, I hadn’t thought about that! You are right!

I actually took a bit more than my I:C ratio is, trying to account for the protein a bit. So I took 1.3U for 16g. Normally that would just be 1U with a 1:15 carb ratio.

Wow, we are the exact same! A1c is between 4.9 and 5.2 also per lab. Dexcom consistently shows about 0.3 lower than that, like 4.6.

Great question! Yes, I did indeed lower my basal yesterday by 50% (from .5 to 0.25) 11:01 AM - 9:21 PM, but not overnight, which held my BGs stable in the 80s but may have also contributed to today’s morning high.


That is definitely my goal!! I’ll try 2 drinks tomorrow, without the cheese. I was thinking the cheese for extra protein, but forgot about all of the fat it has slowing digestion! :frowning:

how many calories do you generally eat per day? and how many carbs and protein do you take in?

wow, you must be very insulin sensitive!!! in the morning my IC is 1:6.5 and throughout the day its 1:12 and then goes back to .9 until the next morning.

how long do you generally need to pre-bolus for your meals. i can be extremely insulin sensitive in this regard. i cant pre-bolus for more than 15 minutes unless my BGs are really elevated. just curious.

PS: but i forgot to mention that once i am back to swimming full force, my afternoon and evening ICR is 1:14 and sometime even 1:16 depending on how hard i swam that day.


To be honest, I don’t really count :frowning: I usually have 60-75 carbs / day, but that will definitely increase w/ these nutritional drinks, maybe by 30g+. I’m not adverse to carbs, I just have a hard time managing BGs with them. I’m vegetarian but not vegan - I eat dairy and some fish. I think I should reduce the cheese though! :slight_smile:

Wow, that is a wide range for IC ratio making it even more difficult to manage. Mine is pretty much the same all day.

Pre-bolus is usually 30+ minutes depending on current BG of course. Wow, insulin works fast for you. Are you using Humalog? That’s what I’m on.

Oh, yes, that makes sense with all the swimming you do would make your ICR more sensitive. I’ve noticed that in my body as well.


i use NovoLog. used to use Humolog, but when i was first dx, there was no fast-acting insulin, so i was on R, NPH, Lente, and something else which i cannot remember. but, my point being, when i was taking R to cover my meals, i only waited 1/2 hour before bolus and eating. do you think that b/c your ICR is so low that that is why you have to wait so long between bolusing and eating? i wonder if eric has the answer to that. i am very very curious. if i wait even 20 minutes after i bolus, i will begin to crash.

just my opinion, but i eat a lot of cheese and nuts and any protein or fat i MUST bolus for. so, my insulin dosage doesnt just depend on the carbs i am eating. its a real PITA, if you know what i mean.

also, i estimate that i eat between 1,500 and 2,500 cal/day. not 100% certain, though. i might consume about the same amount of carbs as you do. when i was swimming 5 days a week, i was probably eating a lot more!!!

question: do you also have to bolus for proteins and fats? and, are you skinny like me?