Blood sugar rising during workout

Before i start working out my blood sugar would be perfect, then maybe 10 minutes into the workout my blood sugar would spike and not come down until hours later. Why is that and what can I do?

hi @EvieFire , certain workout routines (for some people - lifting weights versus cardio) causes a rise in blood sugar. The most likely (from my observations) is when lifting weights causes spikes in blood sugar The reason it causes a rise has to do with adrenaline, adrenaline (a stress hormone) releases stored liver glucose and increases insulin resistance - so your blood sugar goes up.

There is no easy answer, for some people repeating the workout eventually lessens the effect. For others, starting at a higher blood sugar or eating before works, and some people need to balance insulin and exercise to try to contain the rise.

I often mix workouts to include a short warm up, then anaerobic (weights) then aerobic - like a jog, a run or a stair climb to lower blood sugar, but I don’t get a huge spike so my strategy may not be the best . for everyone.

thank you for your advice and insight. I do both lifting and running in my whole routine. But ends same. I will give it time more i do it and see how it effects me from then on.

Yeah this happens to me when I lift weights sometimes. My doctor told me it was probably adrenaline and some other hormones.

But be careful if you are taking insulin. I would often crash when I would try to correct.

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thank you for the heads up! appreciated

My son had the same issue playing soccer. His number would go from low 100’s to over 300. The sweet spot was to eat and give insulin 3 hours before games. The remaining insulin at that time along with his exercise allowed him to maintain his glucose levels! An hour earlier if he would perform at that intense level he would drop extremely fast.

It’s a balance and a little trial and error.

Good luck

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thank you for your help, trial and errors aint fun but eventually find something that works :slight_smile:

I feel your frustration, i get a huge drop at the beginning followed by the liver dump and a spike followed by another crash . I have started breaking up my exercise into smaller time frames over the day to lessen the bg effects. I know it lessens the exercise effects but coping with the BG effects has lessened enough that i can still exercise .

I have this issue if I exercise when fasting. I actually prefer to exercise when fasting because I know I won’t tank especially with cardio. If I do it right in the morning though, it usually combines with my dawn phenomenon and I need some insulin to stay in range. For me personally as soon as I see 110 or grater on my cgm I have to take a small amount of insulin (usually .5-1 unit) and then carry on with my workout. Especially if I lift and especially if I focus more on my arms. Legs are different and even if I end my workout high, I come down super quickly and am super insulin sensitive within an hour or so of finishing my workout. Arms I tend to stay higher for longer and then I become really sensitive 3-5 hours later and up to 48 hours after. If you do take a small amount of insulin make sure you have snacks by you. What works for me obviously might not work for you and I would hate to hear that my advice went you tanking without having a good amount of sugar near by!

thank you for your advice and tips! i am taking them into consideration and will be used!

For me, I have generally found that the best time to exercise is about 2 1/2 hours after I start a meal. If I exercise sooner than that, my body does not have enough time to completely digest carbs from the meal, and my blood sugars tend to spike due to the release of what are called counter-regulatory hormones (epinephrine and cortisol)–hormones that allow muscle cells to get enough energy for exercising. In contrast, if I wait 2 1/2 hours before exercising, my muscle and liver cells have plenty of time to absorb and store carbs from my meal. The end result is that counter-regulatory hormones are not produced and my blood sugars do not spike with exercising.

Do you have an insulin pump? Because if you are setting temp basils that may be the issue but also it could just be how your body reacts when you workout.

i do have an insulin pump. i am not setting temp basils but i think it is just how my body reacts