Managing your blood sugar levels with unplanned exercise

I log into work around 4:30 am. I have an eliptical and a bicycle in my office. If there are no emergencies at work I like to jump on one of them for 10-15 minutes, and hopefully I can do that several times during the day. The problem is that my sugar is between 100-130 at that time of the morning. So if the exercise is unplanned then my sugar level drops. I don’t have time to exercise in the afternoon or evenings so that is why they are in my office so that I can take advantage of slow times at work. Is there any way to keep my sugar at a good level during this time. I usually end up going low and then having to handle it.


Do you use insulin pump or pen/syringes ? Or oral meds?


Pop a few carbs🍭. Quick action to cover unplanned exercise.


I use an insulin pump. I reduce my basal when I am outside riding my bicycle but that is a planned activity. Reducing my basal 2 minutes before I exercise doesn’t seem to work. This morning I did down a cup of juice right before I rode. It helped that I didn’t bottom out but now I am at 51 so will have to eat/drink something. I was at 136 when I started to ride.


Hi @HippieNerdBabe

A basal reduction right before you start can be helpful for keeping your BG from tanking if the exercise is longer, but also it can help after the exercise is finished. You become more insulin sensitive, so keeping it reduced after you finish can help prevent the lows that follow the exercise.

As an example, right before you start you may do a 50% reduction for an hour, even though the exercise is only 15 minutes.

Since these are short segments, 10 or 15 minutes or so, tell me when you drop. At some point after the exercise, right? For longer durations of exercise, dropping during the exercise is normal. But for shorter ones like 10-15 minutes, the drop would generally be afterwards,

Do you eat breakfast in the morning? Can you tell me about that?

Is your goal more fitness oriented, or for weight loss? If it is more for fitness, then taking carbs to prevent the BG drop is good. But for weight loss, taking carbs somewhat defeats the purpose (not entirely, because the exercise does help your metabolism, so the exercise is still helpful, but taking in the extra carbs is just not ideal if your goal is for weight loss). So the best solution depends a little bit on your goals for exercise.


Yes, you are correct. I am dropping after exercise. I will try your recommendation about dropping my basal for an hour. I get up around 4:15 am and start working between 4:30 am - 5:00 am. I live on the West Coast but am still working East Coast hours. So I try to fit in the exercise anywhere from 4:30 am to 7:00 am. I eat usually between 7:00 - 8:00 am. 95% of the time it is oatmeal. And my goal is fitness oriented however I would prefer not to eat just so I can exercise. There has to be a happy medium (??). I manage much better with planned exercise like in the summer when I take a long lunch and go for a bike ride. Sometimes that backfires on me when I’ve eaten a Clif bar and reduced my basal and then get called into a meeting. But thankfully that doesn’t happen very often. This time of year I am very busy at work so trying to plan exercise during the day doesn’t work. Working 12-14 hours is normal.


Generally speaking exercise drops your BG because 1) your body is burning up glucose to fuel the exercise, 2) your body becomes more insulin sensitive, and 3) your insulin is getting absorbed faster as your blood moves faster in your body and your body heats up.

So the easy options are to either reduce basal, which takes a little time, or take in carbs.

But for issues with not wanting to take in EXTRA carbs, the other possibilities are:

  1. Possibly timing your exercise so you can have more time to reduce basal before

  2. Timing your exercise so you can eat a meal afterwards (you are going to eat lunch anyway at some point, so that would not be “extra”)

  3. Timing your exercise so that it is right after breakfast. (Possibly delaying your breakfast until right before exercise. Since you eat breakfast anyway, that is not “extra” carbs.)

  4. Or…micro-dosing of glucagon!

Does all of that make sense?