Weightlifting raising blood sugar levels?

Hi Everyone! I am wondering if anyone has any thoughts on this, or how to solve it. I have been doing some weightlifting/high intensity exercises lately, while on a rather low carb diet. I am Type 1. I am finding it very peculiar because for the first time exercise seems to be RAISING rather than LOWERING my blood sugars. Examples:

Saturday, went to a CrossFit intro class. Now, CrossFit is very intense - I checked my sugar before I left, and I was at 113. I ate a Larabar (31g fruit/nuts) because I was afraid I would go low during the workout. When I came home from class an hour later, I was at 213 and had climbed to 261 within 20 more minutes. Took insulin, ate lunch, and it came right down.

Tonight, I checked my sugar before I went to the gym: 166 (odd that it had climbed from 101 after lunch and I didn't eat anything carb-heavy, and took insulin to cover, but that's another question...). I ate an egg because I was hungry (no carbs), and just came home after 30 minutes of bodyweight exercises and lifting. I am at 225.

I am a strong person but I don't lift incredibly heavy weights or anything. I think that the raising of my sugars may be due to the fact that I am not recognizing carbohydrate in the same way, so maybe my body is "freaking out" and releasing some glucose stores into my bloodstream when I exercise?

I'd like to continue exercising in the same way, but I am not sure whether to eat prior or take insulin prior - and if I eat, what to eat?

Any thoughts?

(I am currently taking a split dose of Lantus and Novolog for meals).

i have a friend who plays highschool football, and he needs to go on a 250% temp basal rate while he’s playing, or he’ll wind up at 400. His doctor suggested that it’s the adrenaline that’s spiking his BGs, since he doesn’t run high during practices or normal workouts.

Hi Sarah. Yes I have been through this as well. (Lantus 1 x night, humalog)

For me, it’s an adrenaline thing for sure. Relaxing, non-competitive activities (swimming, jogging, friendly sports) make my BG go down. As the competition and intensity levels go up, so do my blood sugars. Almost every time I play pick up ball I get a spike and I have to take an insulin shot between games. So frustrating, I know, because exercise is what we’re supposed to do…and then it backfires on us. Type 1 diabetes always plays dirty :frowning:

My sugars went through the same thing when I decided to start weight training…especially when I trained in the morning. Resistance training at very high intensities puts your body under a lot of stress. Stress = adrenaline + glycogen dump = high blood sugars.

My advice. Train hard but try to stay relaxed as much as possible mentally. Your body eventually will get used to the stress and will not “freak out” so much. Just keep training (Crossfit is awesome!!) and experiment with your pre workout meals and shots. Don’t be afraid to check during workouts or even classes, and keep the sugar treatment handy.

Things will keep changing, but eventually your body will become more predictable.

Thanks, Dino. Yeah, it is seeming like it will be a constant experiment. I have the same thing as you happen (go low) with more “relaxing” sports - yoga, dancing, frisbee, hiking, etc. I am going to keep going because I do like the exercises I’m doing but definitely keep a close watch on it. Glad to hear I’m not the only one this happens to!

Weightlifting can really drive your blood sugar crazy. Mine typically jumps about 100 mg/dl. A big factor is that the stress of the exercise drives your body to release blood sugar and if you don’t have much insulin on board it can cause your blood sugar to soar. This happens in competitive sports and it happens in exercise which is really intense. Sheri Colberg has good advice for the diabetic athlete (www.sheri-colberg.com) with her book “Diabetic Athlete.” A good way of managing things may be to eat before exercising and taking insulin to cover those carbs. Having circulating insulin may well help suppress the glucose dump. Even if you do find that you rise during exercise, that is not necessarily the end of the world. With practice, you can take post workout nutrition and figure out your proper bolus to have things work out fine. Everyone is different, and sometimes your blood sugar will react in strange ways, but you will figure it out.