Tips on how to exercise without having low blood sugar

Hi guys,

My Name is Jessica and I am 19 years old. I was diagnosed with type 1 about 3.5 months ago. Since I have been diagnosed, I have tried a few times to get into my old running and weight routine at the gym. However, on three occasions I have experienced lows after working out. Right now I am giving myself injections and do not have a pump. I have tried eating snacks before working out and drinking Gatorade while working out. I was just wondering if anyone has any other suggestions of things I could try so that I do not have to lower my pace and keep taking breaks. Thanks!!

One tip that I learned when I had a personal trainer was to not inject your insulin in the area you are working that day. So on leg day, I’d inject in my arm instead of my thigh.

It can be hard to avoid lows, I generally find I go low about 4-6 hours after exercising…how the hell am I to predict that? haha

You can’t always avoid lows but some tips are to have a small snack with 15g of carbs if your bloodsugar is less than 100/5.5 and you can also try lowering the meal dose before working out. So if you eat lunch at 1pm and plan to work out at 2pm or something, try dropping one or two units from the insulin you take at 1pm.

It’s a lot of trial and error to figure out what will work for you. The best thing you can do regardless is make sure you have some dex tabs on you when you exercise and your tester; when I was running I’d carry sugar, some change (to get more sugar if close to a store) and my glucose kit in a fanny pack along with my cellphone in case I needed help.


You should talk to your doctor about lowering your long acting insulin on running days. That may help. But I am not a runner so I have no idea. I do crossfit and have the exact opposite of what you are experiencing and go high during workouts. Trying to find my own happy medium right now as well. It is so much trial and error and writing down to know what works, what doesn’t work.

I hope that you will figure out something that works for you soon! Hope others who run like @MariaKhristine can be of some assistance to you!

Hi @Jbrown94, and welcome! As @Gina suggested, lowering your long-acting insulin may help. I won’t be the best resource, though, because my sugars actually tend to rise when I go running!

Are your lows immediately after working out? Or is it after showering? For me, taking hot baths and/or showers lowers my blood sugars. (No idea why; another T1 once suggested that it is because the heat makes it easier for my body to absorb insulin more quickly.)

But if it is during the course of your workout, then the only thing I can suggest is to anticipate when you’ll be starting your workout and start trying to raise your sugars (maybe to about 150 or 160) about an hour beforehand. One thing that always elevates me quickly is yogurt. The other morning, I was 61 before my run. I ate yogurt about 20 minutes before I left for my run; and about 15 minutes into my run, I was on a path up, and by the time I got back home, my sugar was 159.

It’s awesome that you’re trying to get back into your routine; great job! And since you’ve only had T1 for about 4 months, it’s possible that your body is still producing a little bit of insulin (honeymoon phase), which could account for the lows. It’ll probably take you some time to figure out what your body needs, and to figure out what foods work best for you pre-workout. Good luck! And I’m glad you found TypeOneNation. I’ve had T1 for 25 years and only just found it last year. I wish I had known about it sooner! Feel free to message me if you want to chat a bit more about any exercise-related things, or anything T1!

Thanks for all your replies! I will definitely try out your suggestions! @mariakhristine to answer your question I usually go low right after working out. So I guess I need to just raise my blood sugar up higher before exercise

I’ve been diagnosed for six months and had lows every time I would run for the first month. Eating a little protein like peanut butter crackers or protein granola bars before has helped me avoid the lows.


Hi there!

I went to the exercise seminar yesterday at the Type One Nation conference in Austin, and there is so much to know!

Avoiding lows can be tough, but here are some things you can try -
(1) reduce you’re insulin bolus (I reduce 50%) if you are exercising within two hours of eating
(2) when you inject, try using a shorter needle (if you aren’t on the shortest one already) so that you only inject into the fat layer, and not the muscle. If you inject into the muscle, when you work with that muscle the insulin reacts twice as fast.
(3) try even working out in a cooler area, which you may not have a choice if you go to a gym. Heat makes the insulin rise to the skin and react faster (which is why you should never shower/bathe within 15 minutes of injecting)
(4) make sure you are eating/drinking high glycemic index foods constantly throughout the workout. I play tennis 3hrs/day and I literally have to eat crackers every 10 min or I crash.
(5) If you eat right before you work out, remember you have delayed digestion. So if you eat dinner and get on the treadmill right after, you don’t start digesting that food until you are done, so you can actually bolus after the workout as well.
(6) Look into getting a CGM, it’s been my life saver since I got it!

I hope this helps!

Great advice! Just to let you know you react more quickly when you shower because the heat increases the blood flow to the skin, causing you to react quicker to the insulin.
This is why a lot of people also have to cut down their insulin in the summer!

Late to post…I just joined. I had the same problem. I’m on lantus. Been T1 for 20 years. Without fail I drop when I work out. My Dr had me decrease my Landis from 35 to 32 units when I’d work out and def eat protein snacks be for working out and getting my sugar up to about 160 as other people stated. Any other tips I’d like to know as well I still struggle…trial and error!

I’ve been T1 for 27 years, and a runner for 20, and I totally agree that you will ultimately have to find an approach that works for you. What works for me is pretty simple: I run first thing in the morning before I eat (no bolus) so I don’t have extra insulin to deal with. If I must run later in the day, or am too starving, I take 1/4 the bolus that I would otherwise have taken. This may be different for you, so you’ll have to experiment. What I have noticed is that when it’s been a while since I’ve run, my blood sugar will INCREASE when I begin to exercise, (I assume because my liver has a nice reserve of sugar,) but if I’ve been running consistently for several weeks, then my sugar will go down much more quickly, (liver running low.)

Rterek, great advise. I have been a runner for 25 yrs and stopped when I had a terrible planters injury. I have not laced up in 3 years! I think I will get started again and use what I have learned here and Rterek specifically. Wish me luck getting this tired T1D of 31 yrs body back in shape! I have a Dexcom CGM now and plan to use it as I exercise. I do realize it has a 5-10 delay. Anyone jog with a CGM? do you leave the pump off if jogging less than one hour?

Look into Niacinimide and Vandium> Might be able to cure type 1 if caught early. That is what I read. I have been a type 1 for 31 years. I would try it’s only vitamins!

Good Luck!

Be a research nut!!!

Oh give up diary immediately at least look into it. I believe dairy was the reason I developed the type 1 when I was 13. I drank pasturized milk with every meal as a boy.

Let me know how you do!

My heart goes out to you! You have to a warrior!!!

Eat to live not live to eat!

Years ago when I was on Lantus, when I knew I’d do significant exercise in a day (more than an hour) I’d reduce the Lantus I’d take for that day. That was only mildly useful because I didn’t always know in advance. One advantage I love about having a pump is that you can to a temporary basal before, during and after exercise (trial and error for how much to reduce the percentage during those different periods). One thing I was reminded of recently was that exercise increases your sensitivity to insulin including up to several hours following exercise so that explains post exercise lows.

As others have suggested, eating during and after exercise, not alot but enough to keep your BGs in a proper range is a good idea. I’ve found the Hammer Gel from Hammer Nutrition is really good because it is a more complex carb (I think long chain maltodextrin or something) but basically it helps a smoother curve on your BGs as opposed to some of the other simple sugar products, Powergel, Gatorade, etc., that can tend to spike, then drop your BGs.