Can Exercise Raise Blood Sugar?

I know that overall exercise is supposed to lower blood sugar levels, but I have also read a few things that say it can raise it. I’ve noticed this happening to me a few times and I don’t know if I’m doing something wrong or just have a weird body!

For example: not long ago I exercised first thing in the morning before eating. When I got up my blood sugar was around 105. When I checked it after exercising for about 45 minutes it had gone up to 122! Obviously, this was not the effect I was looking for.

Just today, I tried exercising around 40 minutes after eating. I had more risotto (rice w/cheese) than the amount I would normally have and also a small dessert, and I was afraid the extra carbs would raise my blood sugar, so I wanted to work it off. I did some cardio walking with weights and a little yoga.

When I checked around 2 - 2 1/2 hours after eating, it was 132–high for me.

I think someone said you should wait longer after eating to exercise, but doesn’t that let the glucose from food just sit there in your bloodstream?

Any ideas or ‘it worked for me’ suggestions?

(BTW, I am considered ‘prediabetic,’ type 2, and don’t use insulin. )

Thanks for all suggestions!

Exercise is stressful and that will raise your blood sugar regardless of food. It raises your adrenaline and cortisol and these will raise your BG.

This is why I made the rule of minimum 10 miles of mountain biking any less and the BG would go up . You can try and do a lot to insure it goes down or forget about the phenomena, the overall benefit of the exercise outweights the temporary rise in blood sugar.

I dont think rice is an appropriate food for diabetics. Nor is bread nor patatoes.

Hi Sophie,
I agree with Anthony. We have two prediabetics and we watch their diets strongly. They rarely ever have even a spoonfull of rice. It has too many carbs and doesn’t add enough nutritiionally for them. They arre growing but don’t have big appetites and can only eat so much. The bread we limit to 2 slices of 12 grain fiber rich per day. And the only potaotes they eat are small amounts of sweet potato upon occasion. They like the sweet potato and it is a good vegetable for them nutritionally. But the rice is maybe 2 times out of a year and then only a spoonfull By keeping our prediabetics as low carb as possible, the doctor tells us we are protecting their pancreas for as long as we can. Hope this helps.

People disagreed with a premise that if we had adopted an Atkins type diet we would have less diabetes. I am not so sure and I think a low carb high fat diet would at the very least stall the progression of the disease for a long while.

My blood sugar goes up everytime i exercise. It drives me crazy and eventually makes me loose my desire to exercise at all. What has seemed to work for me is this: Get your bood sugar about one or two points above your target range, then give yourself between 4-6 units of insulin. the amount of insulin you will need is different for every person and you really have to figure it out through trial and error. This is what has worked for me, how it helps. good luck.

Dear Rebecca.

For God sakes don’t stop exercising. The rise with exercise is temporary and as you said can be corrected easily. I tend to ignore that phenomena. met 2 ice fishermen once who told me that they stopped exercising for this reason. I told them to stop eating that was even better for blood sugar control.

Anthony , I as a marathoner am in totally agreement with you …keep on exercising regardless of having diabetes …it may prevent :slight_smile:
Highs will come down …it may take 20- 30 hours …finger poke, finger poke through the night !!
And it is not wise to stop on eating …choose the correct foods is my choice of living well !!

Dont worry since I have been on insulin I have not been able to go 24 hours without food even though it would do marvels for the BG to unload the liver occaisionally.

I bet you that if you run a half a marathon the BG would go down. If I do that distance on mountain bike which is way easier than running it will be on the verge of going down.

As Dr George Shehen wrote in the '70s, We are all an “experiment of one”. I’ve tested my glucose levels on a run and after about 30 minutes, the numbers start to go down.

i agree with Anthony. theres a kid i go to school with and everyday after PE his bg was high and mine was low. im guessing the exercise stressed him more than it did me, resulting in our different bg numbers.

I took my blood sugar during participation in racquetball tournament play this weekend. It was between 250 and 300 after strenous matches. Anyone have any thoughts on how this effects decsision making on the court?? I currently take no medication and control through diet and exercise.