Trying to figure out what time of day to exercise and what to eat when going low to not throw off all of the exercise I did

So whenever I was diagnosed about four to five years ago, the weight slowly but surely started putting on.  So far I have lost around 30 - 40 pounds and wan to continue to loose at least another twenty.  I still workout every evening as well as watch what I eat, although sometimes I feel as if the exercise that I do is almost not effective because of having to eat afterwards in order to get my blood sugar up.  Most days I workout in the evening closer to bed time and then have lows all night so in order to avoid that problem I started working out in the afternoon with a mindset of not having to worry about putting on non needed extra calories from lows but just not having to worry about bolusing for dinner but for some reason my blood sugar doesn't go near as low as it does whenever I exercise in the evening, sometimes there is no change in it at all and sometimes even goes high.  I am not just starting to have this issue and wondering if I need more intense workouts? Also, I am wondering when the best time of day is to work out , as well as what is best to eat for low blood sugars after exercising to not feel that the exercise was pointless.

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this is really a hard question.  I'll start out by saying everyone is different.  

for me, if I am going to exercise i need to know if I have insulin on board.  fast acting lasts a minimum of 4 hours after taking it, lantus lasts all freaking day,  my basal rate lasts for 45 minutes.  I have a pump so I can dial back a basal rate but there "aint nothing you can do" about insulin on board except expect a low and eat plain glucose.

here's why it matters for me.  Walking (intensity 3 workout) can lower my blood sugar drastically if I have insulin on board (IOB) or if I walk during a higher basal rate part of the day.  If I know I am going to be walking, I typically only bolus for half my carbs or less if I am going to walk within an hour of eating.  "Lets go for a nice walk, honey" can be terrible if I just bolused for everything.  simply put, it's easier to take more, it's harder to take less insulin.

the real trick for us is to work out and not have to cram carbs and put the calories back.  for me it's all about IOB and it's easier to control if you pump.  Do you think you are working out in the evening within 4 hours of a bolus?  is your basal rate higher in the evenings?  are you on lantus (or other long acting) and are you taking your shot at night?

It can be easier to workout first, then eat.  if it's right before a meal you won't have much IOB from the last meal.  If you are a little low you can just take less bolus, if you are a little high you can eat low carb and bolus for the correction.  

sorry this was long.  cheers.

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Most of the time I do my 60 minute workout about a half an hour after eating dinner which is at 5:30, although if I know that I am going to be busy at that time I will workout in the afternoon which is when it seems like exercise does not help my blood sugar but just lets it stay high.  I have been wanting to try working out in the morning but never seem to have the energy to get a efficient workout in.  And about my basal rates, yes they are higher in the evenings but now my blood sugar is no longer going low after exercising during the night or evening only once in a while it does, not sure why.

Thanks for the advice!

Morning workouts are ideal, but it's not practical if you don't have time or are too tired then.

What you're experiencing with blood sugar not going as low is that your muscles have become more efficient as they get used to the workout.  It usually happens after a couple weeks of doing the same exercise.  It's probably time for different workouts and more intense workouts.  

The only way to avoid having to eat a bunch to cover workout lows is to reduce your insulin.  It takes a lot of trial and error and for me no 2 days are the same.  1tsp. of sugar only has 16 calories, so that's a pretty good way to treat a low blood sugar without adding a ton of calories.

If you haven't read it, get Sheri Colberg's book "The Diabetic Athlete."  She's a type 1 exercise physiologist and the book lists different workouts and insulin and food adjustments to deal with each.

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This helps me out sooo much! I figured that was what was happening because when first starting a new workout I can not keep my levels up but after about a week of doing it , it no longer effects my levels. Would you recommend to keep doing the same workouts that I am doing with the same intensity? Because after doing them I feel pretty tired as if I couldn't do a more intense one or since my blood sugar is no longer going low with the workout to do a better more intense one? Even though I feel as if I couldn't do a more intense one should I try? I really want to lose at least ten more pounds to reach my goal weight of 130. Also, about the trial and error thing, I feel like I have been doing that a lot and still have yet to figure out what is best.

Thanks again!

Also, when first waking up in the morning I find that I do not have enough energy to workout because of not having enough carbs to give me the energy needed for an effiecient work out, do you have any suggestions of what to eat for breakfast before working out?

Wish I knew more!  I understand how blood sugar is affected but I'm clueless about the effectiveness of the exercise itself at the point when muscles become more efficient.  To be honest for me, exercise doesn't really contribute to weight loss.  It's all about calories for me.  Exercise helps me feel better and I think it's good for overall health, but it burns so few calories.  

The people who I know who are really fit tend to walk, bike, and/or run.  They consistently do one or a combination of all of these things.  I'm a fan of swimming, but even years ago when I used to swim laps an hour a day I used to have some baby fat on me and I've read that it's common for swimmers.   Guess it helps us float. =)

For your questions you might check out Gary Scheiner at  He's another type 1 exercise physiologist and has written a couple great diabetes books.  He used to offer good online exercise information classes where you could ask questions, but looks like they haven't done one in a few months.  The live sessions are about $30 or you can see the pre-recorded ones for $20.  Totally worth it.

Awesome! Sounds good! Thanks so much!

I have been working out for the last 3 years cut 115 lbs. About 3 months ago went on the 670G had been on an older model 523 been on a pump since 1993
After changing to the new pump was dropping to 60 after 30 minutes into my 90 minute workout. Tried a number of different things finally found a runners carb jell called GU and now take that just before starting my workout. I still start to drop 30 minutes into the workout not as bad but then the rise from the fast acting carbs kick in and end up at around 120 by the end of the 90 minute workout. These fast acting carbs can be found at any sports store. It works for me also carry them if I am suffering a low.

I will offer another good resource for you - the blog at she has a section on her homepage dedicated to exercise and a subsection about blood sugar management, excellent advice. Lots of other great info here as well, I have learned so much from her! Don’t give up, trial and error are always going to be what this is about! Carol

Hi [music_lover] For me being consistent has been the real key to losing weight. I walk every day. for at least 2 hours some days 6 or 7 (or more). build up your routine slowly but stick with it. Once i figured out I had to take insulin to control my sugar not sugar to keep my blood glucose up things became a little easier… I just started with my first cgm and pump about 8 months ago after using syringes for more than 40 years. As Joe said in an earlier reply everyone is different, and ultimately you have to figure out what works for you, what I do is if I am going to take a serious walk I usually do it after I eat something whether it is a meal or a big snack lots of carbs. 40 to 50 or so, I will bolus but only for about 10 or 15 carbs, and then walk it off. by doing this i just lower the amount of insulin i am taking to account for the exercise rather than eating considerably more. although sometimes I exercise enough that i do need more carbs. I keep an eye on my cgm readings and if I notice that it is 140 and dropping I have a granola bar. It will usually stay even and actually go up to about 170 or so before it comes back down. when it hits 140 i have another granola bar. Usually if it goes much below 140 it plummets so I try to keep it about there when i exercise. Every day is a little different and i keep my plan flexible to account for that. I have lost more than 50 lbs since I started with the walking (about 3 yrs)