Swimming and Libre 2

[Laura P]

Hi all,

I've just about gotten myself back to swimming about a year and a half after diagnosis (major BG drops initially during exercise put me off). I've been using the Libre 2 for a long time now and it works wonderfully for me most of the time however I still get rather dramatic (but predictable) drops when swimming but after the first scan my sensor comes up with the 'Glucose reading error' which is incredibly unhelpful when I want to keep swimming. It stays like this for about half an hour after I've finished then the same sensor returns to normal use.

Any ideas or things to do differently?

 

[Inka]

I just take a blood glucose meter when I swim @Laura P and don’t bother with my Dexcom readings (I had Libre 2 previously and did the same). Blood sugar can move quickly during exercise so I never trusted the Libre anyway. I just start my swim with a blood sugar around 9 and get out at regular intervals to check it and eat a Dextro if necessary.

 

[Laura P]

I just take a blood glucose meter when I swim @Laura P and don’t bother with my Dexcom readings (I had Libre 2 previously and did the same). Blood sugar can move quickly during exercise so I never trusted the Libre anyway. I just start my swim with a blood sugar around 9 and get out at regular intervals to check it and eat a Dextro if necessary.

Thanks for the input! I hate the idea of having to get in/out of the pool multiple times, nevermind finger pricking there but worth considering

 

[Inka]

Thanks for the input! I hate the idea of having to get in/out of the pool multiple times, nevermind finger pricking there but worth considering

It’s not multiple times @Laura P Maybe once or twice if I can feel I’m ok or my blood sugar is staying above 6. Starting at 9, I can be confident things are ok early on. I then judge when to retest. I’m there with children so my activity can be quite unpredictable. You might only need to test once

 

[Laura P]

It’s not multiple times @Laura P Maybe once or twice if I can feel I’m ok or my blood sugar is staying above 6. Starting at 9, I can be confident things are ok early on. I then judge when to retest. I’m there with children so my activity can be quite unpredictable. You might only need to test once

When I swim I can't tell that I'm dropping until it's far too late. And I lose 10mmol (?) with the amount I do and don't want to risk it too much more (or starting too high or overdoing corrections or take too many sugar tabs)

 

[Inka]

When I swim I can't tell that I'm dropping until it's far too late. And I lose 10mmol (?) with the amount I do and don't want to risk it too much more (or starting too high or overdoing corrections or take too many sugar tabs)

Yes, it’s harder to spot drops in blood sugar when swimming. If I’m having a day like that (I find the coldness of the water affects it, along with other things) I test at regular intervals.

That’s a big drop. Do you reduce your mealtime bolus beforehand? Do you have a pre-swim snack?

 

[helli]

When I swim I can't tell that I'm dropping until it's far too late. And I lose 10mmol (?) with the amount I do and don't want to risk it too much more (or starting too high or overdoing corrections or take too many sugar tabs)

That is a big drop.
Have you made any changes to minimise the drop?
I am not a swimmer but exercise a lot on dry land.
Things I do to min big drops are
- start a little higher BG
- take in carbs during exercise. This may be a little harder when swimming but I found drinking diluted fruit juice rather than water maintained my levels better than downing lots of fast acting carbs once my levels had dropped too far.
- most importantly, exercise with NO active insulin on board. This means exercising about 4 hours after my last meal and bolus dose.

 

[Laura P]

I swim mid morning when I'm usually sitting high from breakfast. I have tried halving(+) the active dose but it didn't lessen the drop. I could try fruit juice as eating doesn't seem to work but timing wise it would be incredibly difficult for me to not have anything active in the system (rubbish options for swim times). Or I think maybe I need to figure out a slower acting carb for breakfast!

 

[Inka]

Perhaps the breakfast insulin is getting going by the time you swim so contributing to the size of the drop @Laura P ? I used to swim in the evening but now it’s usually the morning with the children. I cut my breakfast bolus and usually add a pre-swim snack like a chocolate bar or part of a bar, with enough sweet carbs and some longer lasting fatty carbs. Flapjack is also a good choice. I eat that just before getting in the pool.

 

[rebrascora]

Why not have a low carb breakfast like an omelette with no bolus insulin, the days you swim, then not only will there be no active insulin but the protein release from the eggs will help to buffer the drop from the exercise.
Which basal are you on? If Levemir, you could reduce your morning dose on the days you swim as another tactic.