I know that mildly elevated blood sugar is common after intense exercise, but mine was really high the other day.
I do a ~24 hour fast once every week. At about 21 hours in, I checked my BG, which was in the 80s (a little high for me fasting, but not bad), and then decided to do some exercise. I did some jogging for 15-20 minutes, and then ran some intense interval sprints. I was pretty worn out by the end. I got some water and went home. About 20 minutes or so after the workout, I checked my BG again. It was 143. That didn't seem right, so I checked again. And then again. All the results were within 5 points of the original. It took a couple hours to come down. After 3 hours it was down in the low 70s.
I am young and healthy and usually have very good glucose control. I have a nice low fasting glucose, and my postprandial glucose seldom exceeds 100 -- even with potatoes.
I suppose it might have simply been a lot of adrenaline from the workout freeing glycogen in the presence of low insulin, but I've never seen a post-workout result that high. Usually it's no higher than ~105.
Has anyone else here ever seen post-exercise glucose this high?
asked byDavid_1 (195)
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on December 27, 2011
at 06:55 PM
I've been a Type-I diabetic for 41 years now and blood sugar levels still frustrate me even though I'm a runner, CrossFit enthusiast, and road biker. I've looked into this for numerous years and read many books about it. Your body releases glycogen from your liver when it realizes you need the energy for your workout. Your liver doesn't realize you have diabetes of course and pumps out what it believes you are in need of. Under normal condition your body would also pump out a bit of insulin to process the glycogen. So unless you have a tiny bit of insulin to help the process along your blood sugar will rise. This is more pronounced when engaging in anaerobic activity like lifting weights. Running will usually not make the blood sugar rise much unless you've miscalculated your food intake prior to running or just didn't reach your usual heart rate during your run.
It seems a bit counter-intuitive to take insulin before working out but with a bit of it your glucose will sit, unusable, in your blood stream. Remember, insulin is the hormone that processes the transfer from the blood stream across the cell membrane so it can be used. A little bit goes a long way during exercise so don't over do it. I'll usually take about 1 unit of Humalog before going out for a 3 mile run. of course, I'll check my BS and make sure I'm in my "running range" of 125 - 140. By the time I get back my BS should be between 80 - 100, just where I like it. A slice of peanut butter toast is plenty for the 3-mile run, btw.
What I find to be the case more often than not are miscalculations in food intake verses insulin dosage for the exercise done. It's a tricky mix.
on April 06, 2010
at 11:46 PM
I would send you to Robb Wolfe's site and listen to Podcast Episode 22 related to high fasting BG and Cortisol levels....it doesn't exactly address your issue of post workout high BG but it may be involved with your cortisol level.
Listen to many of the other podcasts and you may glean an answer. There are 21 others. If anyone would know, I think he should. He is very much a paleo nutritionist and advocates proper exercise regime and proper recovery time for his clients at his Cross Fit Center in Chico, Ca.
You can submit a question and he may answer it directly in an upcoming podcast.
on April 29, 2010
at 02:50 PM
Yes I have seen blood sugars that high after intense (Crossfit) workouts. I imagine many people do but just never know it because they aren't monitoring their blood sugar levels. I monitor because I have a genetic variety of diabetes called MODY (the same kind that Jenny of http://diabetesupdate.blogspot.com has). High blood sugars after intense WODs don't concern me too much though as long as my overall health is good and my A1Cs are still low.
Update: Last night I did a intense Crossfit workout called Fight Gone Bad. About 5-10 minutes after the workout I started feeling woozy so I tested as soon as I got home and found it was 206 mg/dL. That is extremely high for me - the highest I think I've ever seen is 250ish. 20 minutes after that it was back down to 165, and after that I stopped testing. Since I'm not on insulin I'm not sure there is much I can do about high blood sugars like these other than just let them fall on their own.
I'm curious what the result of an intense workout like that after 10-14 hours of fasting would be (when my insulin sensitivity is increased) vs. intense workout like last night after a normal day of eating.
on April 07, 2010
at 07:04 PM
Dehydration can also cause blood sugar to go up. Type one diabetics are instructed to call their doctor if they vomit or run a fever because of the possibility of dangerous hypos.
on April 07, 2010
at 09:12 AM
My blood glucose certainly goes up after exercise. Fasting at 68 mg/dL, post-exercise 100 mg/dL.
on April 07, 2010
at 12:19 AM
Yes, it can happen. There are many many reason why the body produces insulin, exercise is NOT an insulin burner. Exercise, if you get the heart rate pumped up ( 60-70 % of max- you do need a HR monitor- as important as a glucose meter in my opinion), will improve the mitochondria action in the cells which is the single best thing a diabetic can do. This will help your numbers overall. What stimulates insulin production in people differ. Sometime after a work-out, I???m find, others times it is high but that number does NOT bother me as I know, it???s the long term effect I am working for. Diabetics need to test more often then they do and try to get a feel as to when insulin is high and why.
on March 06, 2013
at 07:26 PM
My last evening glucose test was 106 I ave 120'- 140's.. This morning we had about 7 inhs of wet heavy snow..I maneuvered my big ole self propelled snow-blower around For about two hrs I did not have any breakfast but did take my morning diabetic pill. When I came into the house my pulse was around 85 or so I felt good so I tested my glucose. It was a whopping 213 What would cause that jump?? [email protected]
on December 27, 2011
at 01:44 PM
I am a 65 yrs old soccer player. And I run regularly. Today I started out before breakfast at 98. After 30 minutes of running I was up at 132.