Exercise and T1

I am recently diagnosed (sept 2014) and interested in getting back in shape. I was hesitant to start exercise without having a CGM. I have had it for a few weeks now and LOVE it- but even with the cgm I have not been able to figure out the “secret” to exercise without going low. Today, for example, I was 3 minutes into walking on the treadmill when I got the double down arrows on my cgm. I ate a few glucose tabs and kept going… Managed to go about 15 minutes before I got too nervous that I was going to completely bottom out. It is so frustrating… Trying to do something good for my health and I can’t get through more than 15 minutes!!! I am just so frustrated any tips would be helpful. Also I am on MDI - have started reducing my fast acting insulin w/ lunch as I usually work out around 1pm after a light meal. Thinking that having any extra insulin running through my system is contributing to the double down arrows during exercise, although reducing it hasn’t helped at all.

I used to be super active before diagnosis, and I am just feeling super defeated right now because I can’t even do a 30 minute walk without diabetes rearing its ugly head. Help please!!!

Don't be discouraged. Lots of T1Ds exercise hard and manage good blood sugar levels. The simple answer for your exercise is to either give less insulin or eat more food before you exercise.

Timing of food, insulin, and exercise is very important. You might try to eat a normal, not light, lunch but only take about 2/3 of your normal dose for that meal. Then start to exercise when your meal dose is peaking, about 60-90 minutes after taking the insulin. Do you take your insulin before eating? How long before?

You may need to experiment with the size of the meal, size and timing of the insulin dose, and timing, intensity and duration of the exercise. Since there are more than a few factors at play here, I would recommend getting a small notebook and writing everything down. That way you can draw the right lesson from each experience. Step by step you'll eventually discover the formula that works for you.

Don't give up on exercise! It's a big deal. A persistent exercise program is key to managing your diabetes well. Good luck!

I have similar problems if I try to do a long intense cardio workout, like biking. I have biked for years with T1(dxed 3 years ago) and have never figured out how to keep my sugars from dropping low. I never bike more than 1 hour and have tried everything from stopping insulin to eating before and during, and nothing keeps my levels up. Luckily, they seem to drop to a certain point every time like clockwork and rebound quickly after I am done, so I have accepted these low numbers as a trade-off for good quality exercise. even my endo seems ok with it given how predictable my numbers are every time.
If I do HIIT sessions or weight training, the results are opposite. then my levels go up and I need to bolus beforehand. You just need to keep experimenting to see how your body responds to different techniques.
Just don't give up...the unstable bg numbers are a small price to pay compared to the benefits you gain from exercise!

Oh man, exercise…
just remember to exercise to feel good, not to lose weight.
then, find out what works for you! try one thing, find out what it does, then adjust.
only adjust ONE parameter at a time, and be patient. and remember, sometimes you can do everything right and still get a messy result. dont feel bad about it, just acknowledge it and move on. i have been in this circus for almost 11 years and sometimes still get results that i cannot understand.
after all, the most important thing is to hold your head high and keep on going strong!

It's all about balance! I try to do cardio things like walking/ running/ elliptical when I don't have any IOB, mostly after work. I've done quite a few group runs with folks from a local running store but those are mostly LSD (long, slow, distance, ha ha!) runs on weekends and I try to get up at like 4:00 AM and eat quick so the insulin is mostly done before we go. It's a pain but I almost always feel better after I run. I've run with IOB but it sort of gets in the way of the experience, I end up eating and running and all that, which isn't as much fun as just running.

I think I get the most useful data from consistent, shorter runs during the week, I get home, test my BG and run and seem to get decently consistent results that suggest that "pregaming" about 10G of carbs will take me 3 miles. I'm 47, about 185-195 lbs (towards the high end of that now, need to run more!) so YDMV but I've tested it and can get home at 90 and have a glass of skim milk, run 3 miles and be pretty close to the same when I get home. I always take something with me but, if I'm running, I don't want to jack around with snacks, I want to run. It's maybe easier to eat walking, as I will take the dog along but that's what I've seen.

I agree with your assessment that insulin is causing the double downs. I like to run my basal pretty hot too, eat little bits here and there and bolus heavy too but it keeps my BG down. I was always super skeptical of pumps but, once I tried it, I found it was like night and day, really great for exercising, if I go harder and my BG runs up or down, I can nudge it very easily with a pump. I did my first pump vacation last summer (to go surfing, which is also AWESOME!!) but it was very challenging to control my BG as well!

thank you for your encouragement! It really is all trial and error, and as a slight perfectionist, it's an exhausting battle to fight!!! But I am pretty motivated to master this exercise thing - it has always been a huge stress reliever for me in the past and I know I could benefit both physically and mentally from getting back into it.

I've heard pumping does make exercise more manageable. I think down the road that is something I will consider...don't know if I'm ready for it yet though, it seems like so much to learn. I know I just need to be patient and persistent, it is just a learning curve. Thanks for your input!

I am interested in the responses too. I have not mastered this yet, but I'm certain others have. I am ok with planned moderate exercise at home, I can do a temp basal on the pump, eat a snack and after trial and error have figured out my needs. It's the spontaneous or variable stuff I do that causes me problems. I hike every week, different terrain, distance and time (lot's of variables) and I cannot seem to get it right...ever. Frustrates me.
When I was on MDI I would work out after supper, usually cut my bolus 1/2 for the meal and sometimes have a juice box before. That's what worked for me. I did manage to figure it out eventually.

I started walking/running on the treadmill at home in case I dropped, I was close to family and carbs. I experimented with the time of day, food, insulin, etc. Once I "mastered" it, I went outside and ran/walked. Of course with skittles or sweetarts.
Even when I think I have my crap together, D decides to remind me who is in charge.

Along with what everyone has said, I would add to test often. It's the only way you can maintain good control and be in charge of your health. Good luck!


You would be a good candidate for a pump. I've been T1 for 31 years and pumping for 12, and exercise used to be such a hassle before I started pumping. I'm no athlete, but I'm really active with dancing and hiking. I hated having to pig out before I exercised! Now I just dial down my basal rate (baseline trickle of insulin) about an hour before I start exercising, and it works like a charm. I can set a different temporary rate following exercise, since exercise often has an extended effect on your BG. I still go low sometimes, usually if I'm exerting myself more than expected, but I never have to eat beforehand, and am usually quite stable during and after.

My general approach, fully endorsed by my endo, is to get my BG to least 180 or higher before beginning cardio. I can easily drop 100 points from 40 minutes of cardio and I don't want to be worrying about eating glucose tabs during a workout. I know it's not an approach many around here would agree with, but it works for me and my endo said she knows T1 athletes who get their BG much higher than that before a workout. If I ever make the leap to a pump, I'll probably be able to refine my approach some, but with MDI this seems to be what works.

For me, exercising after a meal-- when there is bolus insulin in my system-- is not s good idea. Getting the blood flowing will invariably cause the bolus to absorb faster. I can work out as hard as I want as long as there is no bolus without and significant risk of going dangerously low, but any bolus is a recipe for problems