Running Low


On my last few runs I have set the basal rate on my pump  at 45% (down from 50%). Although I haven’t had any real lows lately, I have felt that this is not low enough and that I am always in danger of hypoglycemia. I have also been feeling like I am using energy gels too often in order to keep my blood sugar under control (and not to supply my body with carbohydrates).

Yesterday, I had a easy pace 8 mile run planned. The run started off fine including a blood check and a gel after 2 miles. I was running at an easy pace when after 4-5 miles I started feeling week and sluggish. I stopped to check my blood sugar. 61. (I had taken an energy gel just 2 mile earlier). I thought to myself that this may be a false reading, a result of too much sweat on my hands and decided to check again. I wiped my finger on a nearby wall to dry it off and tested.63. Not much better. (I have had a few false readings of 28 lately)

I quickly took another gel and continued running slowly. It did the trick and a few minutes later I felt fine again but I knew that that had been a close call. Any lower and I would have had to stop.

So this morning when I woke up at 3:53am to get ready for my run I decided to lower my basal rate to 40%.  I got out of bed quietly, trying not to wake Jessica and Adam (who were up a large portion of the night) and went to check my blood sugar. It was 136.

A little before 5:00am, as I was about to leave my blood sugar was 115. I knew that was low to start off with, so after a mile I checked again- BS 91. I took a gel.  I felt good and kept on going towards my friends, meeting them a few minutes later.

After 2-3 miles I stated to feel like I was having a hard time keeping up. Normally this would not have been surprising but they were going at my pace. We all stopped to drink at one of the water fountains and I checked my blood sugar again. It was 72. I was very surprised, not only was my blood sugar not going up, it had dropped. I took another gel and continued. I got my energy back, but 2 miles later I was only 93. I decided to not take any chances and consumed one more energy gel. I don’t think I have ever had three of those things in such a short period of time. I finished the run feeling great and strong. When I got home I checked again. This time my blood sugar was 87.

I don’t know what I should do to keep my blood sugar up during my runs. May be I should disconnect the pump and leave it at home, or maybe I need to eat real food before the run. I guess I just need to keep trying.

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Catherine Price
11 years ago

Amy, My “routines” of checking during runs are all a product of highs and lows. It took me a long time, and many test strips to learn when I need to test myself and when I need to take my carb (gels). Before going on the pump I knew my body so well that I didn’t check at all. Now I’m back checking again very often during my runs. I check every 45 minutes (starting 15 minutes in to the run) and sometimes more depending on how I feel (week, sluggish, dizzy) and how low my BS was last time… Read more »

11 years ago

Michael, How did you work out these “routines” that you reference (ie: testing 2 miles in and taking a gel).  I got diabetes less than six months ago and was a pretty avid runner –though not like you! — prior to the diagnosis.  Where I was running 6 miles pretty easily in February, I tried to do 2 miles the other day and had to stop because my legs felt tingly after a mile and a half and my blood sugar was 50.  I carb load before the run, skip my morning insulin altogether, have cut back on my lantus,… Read more »

Dr. Margaret A. Morris
11 years ago

It’s going to be different for every person, but for me, when I work out in the morning, I eat beforehand (a Clif bar) and way under-bolus for the carbs (about 50% of normal). That keeps me relatively stable for the hour of exercise, even with my basal at normal. If I do less planned exercise, I do my best to pre-load the temp basal; that is, I’ll suspend the basal entirely for an hour beforehand if possible, then re-enable half way through the exercise to help with the post-exercise spike I often see. The trick is that if I’m… Read more »

Sam Gellman
11 years ago

I agree with Matt.  The little I exercise it’s always a battle to fight low blood sugar.  I still remember leading bike trips in 2002-03.  I went from giving myself 45 units of insulin per day to 4 units.  No joke.  My total insulin intake went down by 90%.

Every person is different and to make matters worse, every person is constantly changing.  That’s the battle.
Have you tried a CGM?  It can at least help remove some of the mystery it sounds like you’re dealing with.  (though not perfect by any stretch).

Robin Cacopardo
11 years ago

Thanks Matt. my basal rate is 0.45 during the day and from midnight to 5:30 0.65. 40% of that is well over the 0.01-0.05 your talking about. I will start working my way down.
Thanks again

Matt M.
Matt M.
11 years ago

I wouldn’t disconnect the pump entirely, but it seems like your body is telling you to turn down the basal even more dramatically. Typically, when I go for a bike ride, I turn down my usual 0.4 to 0.1 or even 0.05 about 45 minutes before leaving (if I can predict that). Then on the ride I continue at that lower rate, or even sometimes suspend temporarily depending on my numbers. I consume around 40g of carbs per hour in the form of gel or liquid. That’s usually good to keep me around 100-140 for about a 6-7 hour, 100-mile… Read more »

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