First of all, welcome to the site! Glad you could join us.
So that spike you are seeing is your body’s natural response to intense exercise. You won’t spike like that from a slow long run or jog. What you are seeing is normal for a hard and shorter effort.
That is a typical “fight or flight” response. If you were being chased by a lion, your body would want to make sure it does everything it needs to do for you to escape!
Your body releases hormones - epinephrine (adrenaline), norepinephrine, and cortisol. Your heart rate and blood pressure increases. The oxygen that goes to your tissues increases. And your liver releases glycogen stores to give your body fuel.
Everything that is happening to you on a short fast run is the same as it would be for a non-diabetic. The only difference is that the non-diabetic doesn’t see their blood sugar spike because their pancreas automatically releases insulin.
So your spike from 130 to 350 tells me three very good things:
It means, other than your pancreas, your body is working perfectly normal in every other way!
It also means you are not jogging or taking it easy on that run, you are working hard. Your BG wouldn’t spike if you were jogging easy!
And finally, it means you are doing something good with your body. Instead of sitting around playing Xbox, you are putting forth physical effort. And that is wonderful. Way to go!
So here are a few things that can help you:
You do not need a lot of food before a 5k. Most of your fuel will be from the carbs already stored in your muscles. Make sure you eat well a few days before.
You can eat a very light meal at least 2 hours before. Don’t eat closer to the race time than 2 hours! You want to minimize your IOB. A small meal will help you a little bit, but it isn’t absolutely necessary. The key is to be flat before.
You want to try to be as flat as possible, so don’t experiment with something for the first time before the race. Use a meal that you know how to bolus for! Try it tomorrow if you can! Check your BG often and try to make sure you have a meal and bolus amount that will keep you flat.
And now, here is the thing no endocrinologist will tell you to do. I started doing it years ago, and it took a lot of…guts. But I started taking insulin right before the start of the race to prevent the spike. I kept spiking from every 5k race, and finally I decided to have the faith that I would always spike until I took a little bit of insulin.
I don’t want you to rush into that. The first step is to be comfortable and start to believe that you will spike. Also, if you don’t put forth a hard effort and get your heart rate really pumping hard from the effort, you won’t spike as much. So you need to become confident that you will spike, and you need to know that if you take insulin before a race, you really need to run hard so you don’t cause yourself to drop.
Once you are ready to take that leap of faith and take a little insulin right before the race, you want to start with just a little bit the first time. You will need to experiment until you find the right amount. Too much would be a problem! So you start with just a little bit at first, and build up until you are comfortable with the amount, and figure out the right amount.
You have to do it right before you start. If you do it 10 or 15 minutes before you start, that can be a problem!
And remember, if you take a little insulin before a race, you better run hard!
But wait until you are comfortable that you will spike before you try that…
BTW, you probably would not need insulin right before a 10k. That is a little bit different energy system.
Anyway, feel free to ask questions!