Supersapiens - continuous blood glucose monitoring

The sensor takes it’s reading from interstitial fluid (there is a small filament that gets inserted into your skin when you apply the sensor - it’s painless!) - so this isn’t directly measuring your blood and there is an inherent delay (common wisdom suggests 10/15 minutes). The app gives you a trend arrow to help you see where your levels are heading, so if you see they are looking like they are dropping then maybe time to consider some fuelling.

?? I thought the pathology of type 2 diabetes would is commonly known.

So age, genetics, ethnicity and race are what we call irreversible risk factors. Things you cannot change…

If you want a real deep dive, then I recommend this course.

In it, you will find the importance of integrins, how gastric bypass surgery can be curative for type 2 independent of weight loss amongst other biochemical pathways involved in the pathology of type 2 diabetes. It is far from a “it’s all because of lack of exercise and poor diet” disease. It’s complex and interrelated to those irreversible risk factors I mentioned.

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Yes I know that.
Your previous post suggested from my reading that time was a factor regardless or behaviour. Must have miss read or it’s not clear I agree it’s either lifestyle or genetics with that passage of time.

Ah yes, time is probably the biggest factor of all! It’s clear that it is something you develop over time. Like wrinkles. Your skin will wrinkle over time and whether you are in the sun or moisturize affects when you get it. So same thing with glucose tolerance. Over time, many people are less able to maintain glucose homeostasis because the cellular machinery probably ages. This is evident in epidemiological studies of age vs glucose tolerance tests in relation to BMI.

Anecdotally you have people like Beth Stern show up as prediabetic even though from her phenotype, she is waif thin.

Inability to maintain glucose homeostasis or homeostasis in general is highly correlated with time aka aging and is exacerbated by diet.


Time - the greatest leveller of them all… :+1:

Interestingly my elder brother has always been thin (and was fit in his younger days in the Army). Last year he was diagnosed with Type 2 diabetes (basically because he was thirsty all the time!) - they tested his urine and he was basically peeing glucose as his body couldn’t control the levels. Unfortunately he progressed to Type 1. My eldest daughter has been diagnosed with PCOS and was Insulin resistant. The whole area is a complex one and glucose levels are driven by all sorts of factors.

Type 2 doesn’t progress to Type 1 per-se. They’re really completely different diseases that present with the same symptom of elevated blood glucose. If I had to guess, your elder brother was misdiagnosed T2 initially and turned out to be a T1.5 (LADA) upon further (more competent) inspection. Wait till you hear about Type 3 diabetes (alzheimers). :exploding_head:


The point is that you save time. How long would it take you to fine tune your on the bike nutrition to hash out all the kinks? You can definitely tighten that trial and error loop. It’s all about saving time and effort.

I would agree that it’s not as useful to be used in real time because it’s reading from interstitial but it’s also much quicker than if you were measuring not during activity.

If money was no problem, you can just get the latest version of a dexcom and you can see it in real time. Probably not necessary for most but in our type 1 population it’s essential.

i posted above and repost it here. As a type1 diabetic I am using a Dexcom CGM for years. there is a considerable delay of mostly 20min or more in comparision to directly measuring your blood sugar with conventional fingertip-blood-measurements.
and even then the CGM can be up to 20% off when it deals with more extreme blood sugar levels, low or high!

So if really somebody non-diabetic feels that this data is somehow relevant Id suggest to briefly stopp the training, take a precise blood sugar measurement through your fingertipp and continue the workout. It is precise, quick and cheap(er).

I do not rely on the CGM data exclusively, it is way off especially after food and during intense workouts. It gives me the great advantage and lifesaver that the alarm wakes me up at night before something worse happens… but during the day and especially during sports it is not reliable enough for my health nor would it be precise enough for valuable analysis of data during workouts.

So I still carry a conventional blood measurement device additionally with me and rely on the real blood test to give me data for adjusting my insuline injections


That’s unfortunate to hear that. We got two athletic type 1’s here that used the dexcom G6 where the readings were pretty much spot on with fingersticks and there is no delay. The biggest problem would be from the initial placement. Our biggest concern in delay isn’t between fingerstick and cgm as they are both insterstitial measurements and correlate very well in real time. The delay we see is between interstitial and venous blood. During activity, the delay is even tighter, giving even better control.

The sensor is usually placed on the fat belly of the abdominal area and the insulin pump is placed on the upper deltoid.

His glucose control is spot on and generally achieve anywhere in the 4.0 to 4.5 HgbA1c and her control is more difficult because menstrual cycle so we see her in the 5.2 to 5.5 range.

Almost all the insulin doses are based solely on the data from the cgm without the need of the fingerstick.

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very nice to hear it works for some. Interesting though as even Dexcom clearly states that there is delay and no application of insuline should be undertaken solely on basis of the Dexcoms data. But hey, happy to hear it seems still to work for some.

as I said, in my years of using Dexcom there has always been delay, there has always been considerable difference between Dexcom and fingerstick test after food intake or during workouts and, especially during high intense workouts where blood sugar tends to fall very quickly many times the Dexcom reacted with a sensor fault which could last up to 30 min until the signal was fine again and data was sent.

So for me the Dexcom has not been and is not fully reliable as exclusive source for blood levels as much as I would wish it would be. It is not.

my sensor is applied on the belly, always has been, my HbA1c is usually around 5,5%.

For a Type1 I find 4.0 very low.
Asuming regular intense workouts where blood sugar needs to be in higher ranges and even tends to spike considerably after completing sessions someone who wants to reach a HbA1c of below 5% has to have very very low blood sugar outside of workouts. Such person must be undersugared in Hypo all the time.

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It is a young, very active male who has a very good intuitive sense about his insulin doses. Better than what could be administered algorithmically. Also, both individuals are on low carb, ketogenic diets that is the bedrock of maintaining glucose homeostasis.

Are we talking about the same version of dexcom? Here in the US, we are using the g6 which is FDA approved for insulin decisions without finger sticks. You do want to do finger sticks periodically to verify calibration though. The new G7 that’s coming out should be even better. We have other systems which are closed loop with the pump which, of course doesn’t need finger sticks as it is the closed loop, however, the adaptive learning software still isn’t as good as a highly competent human.

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Sure, I have a G6.
and still I find these HbA1c very low, too low.

Ahhh, yea I know what you mean. I’m not one to rule out that he may be a genetic freak though. In any case, that is outside my realm of expertise. That’s between him, his endocrinologist and…psychologist…lol

Ah right, was wondering why it was not showing up on my Garmin. Which beta are you using? I see 7.19 is out.

These are interesting reads, thank you.

What bothers me about my readings is just that if, like today, I do four hours 3500kcal burned, then you can imagine how I was attempting to fuel. I was still not in the optimal range (that being 120mg/dl) for no longer than 20% of the ride. The supersapiens app also does not really distiniguish these phases either. My average glucose for the day is ofc way higher for days like today - but in realtiy this is skewed. The ride was tanked up, beforehand had sugar, and afterwards too - that is the deal for us lot.

Anyway, this CGM is really giving me some insights into my habits. I have some open questions now:

  • how does one really fuel to keep this high level? Sipping sugar water non stop for hours? No bolus?
  • post workout - within 30mins a high load meal/drink should be taken on board. How high? How much? My one today in fact set my levels through the roof - I was really surprised!!!
  • out of all the foods I have eaten, apart from the blindingly obvious like some veg, wholegrain pasta has given me the most stable response and satiety. In addition, my pre-ride meal of some toast with jam on, and a side of protein (yoghurt say, or seiden-tofu) works so well to give me a decent rise up to around 120 and then slowly peter off. Rice waffles, though so low in kcal, are absolute pyro for my blood sugar.

Only above 120 for say the first hour doesn’t seem quite right to me. Because your liver will be dumping glucose into your bloodstream too, probably around 400 calories worth. And you would have say around 1500 calories already in your legs. That’s if you started topped off like you said. Are you waiting to fuel into your ride, or are you immediately starting? Your liver glucose capacity should be lasting longer than 1hr.

Depending on the ride ill do either a bolus or simple sugars, with many rides combining both. My glucose stays 130-140 (finger pricks).

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I tend to wait about min 30 mins but usually about 75-90 mins before I start on the sugar water. Generally speaking, I think some fluctuations are surely fine. Activity level influences it of course. I saw today that after my breakfast, then heading out about 45 mins after - the activity more or less releases the sugar stored up and kept me fine for the SS intervals (for the 75 mins). Having it ‘live’ on my Garmin is really fantastic.

Very much experimenting still. Did 2 hours TR work, followed by somewhat easier for another 2 hours. The Clif bar after the workout caused an initial dip, but then working in tempo, I could see it kept my levels ca 120 for a good hour - this worked well.

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And in the UK you cannot drive if your sugars are lower than 5. If a person always runs their sugars low they can also become hypo un-aware.

Not sure where @Minty_One is based when he refers to “here” but I’d be worried if that athlete was driving with sugars that low though of course he may not drive or they may not have similar regulations where he lives.

Edit just noted the" here in the US" Do they not have similar regs?

Or worse still riding whilst hypo…


Really? I’m in the usa and to best of my knowledge a regulation like that doesn’t exist. Do they actually test drivers like you would for alcohol?

Might be because most our population is 6+ anyways. I like the idea, but the back lash to that being implemented would be huge.