Update #1 on CGM Use

Spike is from Tortillas

Here is a short update after my first two weeks with my Levels CGM - using a Freestyle Libre sensor.

As I stated in the first post I was mostly going to get used to the CGM and how the data works for the first 3-4 weeks and that is what I have been doing.  I have seen spikes when I expected them - such as eating a Pizookie ( https://www.bjsrestaurants.com/menu-item/salted-caramel-pizookie-2) which is a sugar bomb I rarely eat or having some tortillas - in this case only three small ones with some Menudo.  But also saw that oatmeal with cream and nutter and nuts, even with honey and blueberries did not generate the spike I expected.  That said I would really need to do an experiment for me to see how I react to oatmeal with the other items in it.  Also, noticed on my 110 mile ride this past weekend I did not get a noticeable spike, that I can see, from taking in carbs in the form of Gel chews but did see one when done and taking in some carbs. 

To do some of this investigation I still need to learn how to download the native data so I can look closer at the long ride and at the timing of when I took in fuel.  I want to look at some other runs where I did not take in any fuel but just to see what is up.  This is part of my wanting to see how fueling for me works and the timing.

I did notice initially is I had some pretty low numbers when sleeping but over the last week not so much so not sure if it is just a matter of things leveling out or not.  Or maybe just how I ate on those particular days before going to sleep.  Another one of those areas to look at.

Now this may be me but I can really see how this can help one work to minimize spikes.  If you are completive or like a challenge just knowing, via seeing past spikes, that certain foods will spike my glucose I will work to avoid them to minimize spikes.  I am also seeing that my body takes care of these spikes very quickly as while I have seen a few good spikes they are very short in duration.  The flip side of this that applies to most is I can imagine that of one endlessly had these spikes ones body could break down over time.

As far as comfort I really do not notice it is on.  The one thing that is a little bit of a pain - not literally - is the CGM takes the reading from interstitial fluid so is why it is on the more fleshy part of your arm and from others that have used one I was told if you sleep on it you can get some faulty numbers at night.  Truth is for me it would not probably be an issue but as I am a little OCD now I was told this I try and not sleep on that side:). But other than that no issues at all and am about to change it out as the 14 days is ending and even the cover held up well - sweaty running, showers and all.

My plan is over the next two weeks to further see how things affect me and work to avoid some of the things I have already seen do so.  Also, I am going to try downloading the raw data so I can see what I can do with it.  Not sure I will have enough data to do much at Gravel Worlds but do look forward to see how my body reacts during the two back to back races.

This is a chart from yesterday showing nothing much going on during my ride ( https://www.strava.com/activities/9502302658 ) as glucose was stable the entire ride. I took in 157grams over the course of the 6:30 ride but don't see any change in numbers when took in gels.  Dinner was with the Pizookie sugar bomb.  The spike after the ride was when I had some pretzels and almonds when done.

The Start of My CGM Journey

While we do not want to be data driven and controlled - as far too many are - we also do not want to ignore the ability to gather data.  In other words do not be a slave to data but let data corroborate what you know and experience since when you do this you will find over time you will not need the data but better be able to do things intuitively.

So it is with me and getting a CGM.  I don’t have TY1 or 2 Diabetes, and am not Pre-Diabetic and as far as I can tell am not insulin resistant.  Let alone at most times I am relatively lower carb than most and a lot less than many that work out and race as I do.  Yea, I am the opposite of the ever increasing posts on working to convince people they need to take in more carbs than ever before.  Where as for a long time the goal was to take in up to maybe 60gr or even maybe 80gr of carbs an hour the use now is for close to or over double that at 120+gr/hr.  Now I get it - if your paradigm is carb centric and you are not willing to change that paradigm you probably only have one way to go - more and more carbs.  But there is a way to go and it is one our bodies was designed to go - that is to use the fuel - fat or carb - that is needed for the effort or situation at hand.  However after years of training our bodies to rely on one source, carbs, most have to make a n effort to get things back on track

My thoughts and plans for the CGM is to gain more info on how my body works to help my health and performance and also to help others in how to use carbs in a lower carb diet for health and performance.  The Bernal plan is to just gather info for 2-3 weeks and then start experimenting with different foods and timings to see what doe best for any given situation and effort.  In the midst of this will be my run and ride at the Gravel World’s Double the end of August and will be interesting to see what the data shows after the races.  Unlike a certain company that pushes their CGM set up to drive what you do even in a race I am just going to observer what happened and use that data to compare to how I feel and make adjustments.  The issue with making on the fly changes is that as context changes - temp, effort, fatigue and more - so does ones needs and it may not be the same from one time to the next.

As far as the CGM set up I chose I went with Levels.  As a bit of info if you are not diagnosed by your doctor as diabetic or pre diabetic you will need to go the route of one of the CGM health companies to get a CGM as you can’t just buy them and your insurance will not cover it.  While a topic for another day but it is interesting that insurance companies will only cover things when you are already sick instead of covering those tools that may help you not get sick - but that is how they work since sick people are more valuable to the medical complex.  I looked at a few companies and finally decided on Levels as at the moment you had a choice between a Freestyle Libre or Dexcom 6 and for now went with the Freestyle Libre as the Dexcom 6.  Some differences are that the Libre is a little smaller and needs to be scanned every 8 hours to down load the data while the Dexcom is live and downloads the data via bluetooth.  Also, the Libre is good for 14 days before you need to change it while the Dexcom needs to be changed every 10 days.  Then, depending on who you talk to one may be more accurate than the other but if Levels ever moves to Dexcom 7 which I hear is much better it will be good.  As Levels, as with others, is a subscription based you get a new set of CGMs every month and you can change from the Libre to Dexcom when you like or even stop the subscription for a period of time.  You do pay a yearly ($199/yr) fee for use of their software on top of the monthly fee for the CGMs ($199/mth).   Again, you can put the CGM’s on hold when you like and then start again.  My plan is to use one for 3-6 months then take a break then come back near the end of my year plan - actually got a free extra 2 months - and see how things are and decide what I want to do from there.

I am sure there will be more I will do as another aspect of this is to see how my system reacts to being fat adapted and what happens when working out and racing when lower on carbs.  As I have said this is not to have the data drive what I do in real time, even though it may help adjust it over time, but help fine tune my fueling and cooperate what I already know and feel - or if the data says something else change what needs to be changed.  IN working with Peter at Vespa we really want things to be organic and intuitive but also know that data helps to build a foundation that supports what we know.
That’s it for now as I head off to So Cal for work for a month - will be interesting to see how my body does when eating out for month on travel. I have to admit I am sort of a data geek so am really looking forward to this and truly hope that the info I discover will help others so stay tuned.

What is the plan - well as I said this is to be a journey to learn more about how my body functions and to be able to fine tune my diet and carb use for various situations be it just life or racing and training.  The first 2-4 weeks will mainly just getting used to the data and collecting it so I know what my baseline is.  Also, will collect data from the Gravel Worlds Double that is about 5 weeks away which should be interesting in and of itself.  From there, and maybe even some in the 2-4 weeks, I will do some testing of certain foods and food combinations to see how I react.  One thing I really want to find out is about what carbs work best when racing to give me the push I need.  I have already found how some combos spike my glucose more than others - I do not noice it directly but can sure see it in the numbers.

I am sure there will be more I will do as another aspect of this is to see how my system reacts to being fat adapted and what happens when working out and racing when lower on carbs.  As I have said this is not to have the data drive what I do in real time, even though it may help adjust it over time, but help fine tune my fueling and cooperate what I already know and feel - or if the data says something else change what needs to be changed.  In working with Peter Defty at Vespa we really want things to be organic and intuitive but also know that data helps to build a foundation that supports what we know.

That’s it for now as I head off to So Cal for work for a month - will be interesting to see how my body does when eating out for month on travel. I have to admit I am sort of a data geek so am really looking forward to this and truly hope that the info I discover will help others so stay tuned.