Hey I was wondering. When I was on shots with NPH and regular I could ride my bike for miles and miles without ever testing or worrying about going low, what gives, as I go low now with any amount of movement on the pump. 
I do ride now, but have to carb up big time, decrease my insulin and I can only ride for about 1/2 hour before going low. What is that?
I miss my days of riding 20 miles on a Saturday without a care in the world.
Hi Karen
Our bodies change all the time. I hear your complaint. What worked so well for me three months ago, no longer works. Is it because i am three months older? Is it because my body is working at warp speed to help me with my diabetes? I wish. I really don’t know the answer, but if someone else does I want to know it too. Of course if someone knows about a quick fixit that comes in a little tube (like superglue) that I can buy at Walmart, please tell me that one too. All I have left is a little bit of my sense of humor and most of that is gone too. I need a recharge please.
It is all experimental. It took me a few rides to figure out where I should be. I go out for 100 mile rides now, but lower my basal to 50% and take in 15 grams of carbs every 30 minutes. Trial and error, and it changes whenever it wants to, but with the pump it is easy to adjust.
I don’t recommend turning off the pump during exercise or ever. I used to do it, but ended up with some bouts with DKA because I had no insulin. (duh!) As a CDE once said to me, “Non-diabetics don’t turn off their pancreas when they exercise.”
Since insulin peaks in about two hours you won’t really see the affects of turning off the pump until two hours later - when you’re done exercising in most cases. The result is that your muscles are more insulin receptive because of the exercise BUT you’ve got no insulin on board since you stopped taking any two hours earlier = trouble.
Now, I didn’t end up with DKA every time, so turning it off might work, depending on various factors, such as how long it’s off, what your BG was at the time, the length and intensity of exercise - you know, the typical juggling act.
As for what to do while exercising - trial and error. If you’re going low, try lowering your basal rate starting 30 to 60 minutes before your ride. Carb up - not too high - and carry some carbs with you. Bring your basal rate back up at the end of the ride.
It will take some trial and error so keep you testing kit and fast acting carbs nearby - which we should do anyway. Look at the Athletes with Diabetes group for other tips and other people’s experience - also the Diabetics who run Marathons group.
Keep riding!
Terry
Like others have said, you may have to do a little experimentation to get it just right. I have just experimented with different basals, starting one hour before exercise, to get the right amount of insulin for the food I plan to eat and the exercise I plan to do. Also, I would not recommend turning your pump completely off but if you are still getting low you may need to turn it down even further. Try turning down an hour in advance since the basal rate takes some time to catch up with you.
Any form of movement since starting on the pump five years ago, I go low very quickly, so since going on the pump I have gained a ton of weight as I feed my lows and avoid exercise like the plague. I was hoping with being on the pump I could avoid all these lows, but it has yet to happen, but I keep trying.
Gardening on Saturday I lowered my basal to .03 for an hour before gardening and my bgs was 200 and with in a short time I dropped to 102 and felt like crapola. The 200 was not caused by lowering my basal, but other issues.
Today I lowered my basal again to .03 an hour before biking, I biked for only 40 minutes and I was 102 at the beginning, ate 40 carbs and was 159 at the end, I was fairly happy, but still I have to eat a lot to do all this.
I want to lower my basal, not eat, and ride like the wind for hours without eating, is that possible? Not asking for much. 
And yes I have gone sky high later on occasions in doing all this lowering of basals.
I am one frustrated diabetic/pumper.
If you want to ride for hours, it is most likely that you will need to eat. By not eating at least something small during exercise, you limit the amount of energy your body can use which can have a negative impact on getting more trained. However, if you are exercising for an hour or less I can understand not wanting to eat anything.
What is your normal basal rate during the time you lowered it to .03 and do you notice a time of day when this problem is worse? Also are you type 1 or type 2?
Type 1, so no I have no extra insulin floating around that I am producing.
My basal rate during this time is normally .3 (lowest of the day from 2:00-5:00)
I go low constanly with any movement
Thinking about doing lantus again as my basal and just bolus humalog for meals and corrections, to see if the constant fast acting insulin in my system is doing me in.
so you are exercising in the afternoon typically? this is my most insulin-sensitive time and even if I have taken a bolus in the past 3-4 hours it can hit me in the afternoon. what time of day do you typically exercise?
I tried going off the pump for other reasons, but it was very insightful.
5:00 p.m.
how long after your last bolus is it typically? can you think of any other reason that might explain why you drop low so quickly when you don’t eat? do you digest your food easily during exercise? also, what happens if you turn your pump down 90 minutes before? To offset highs after exercise you can try turning up the basal 30 minutes before you finish since the basal won’t affect you right away.
Depending on the type of exercise, I will turn my basal rate down up to 3 hours before exercising.
It is usually after my lunch bolus at noon and I ride my bike at 5:00.
I have tried all of the above.
Today again I rode, I cut my basal back ate 40 carbs and 40 minutes later bgs was normal. 82 at beginning and 112 40 mintues later.
I will try cutting back tomorrow the 90 minutes, hmmm today was 90 minutes, I cut it back at 3:30, maybe I will have to do the 3 hour rule like Maureen suggested, I guess I don’t want to plan and scheme this much.
yeah it’s a bit of work to figure it out but once you do, it gets easier at least for a while until things change again! it is definitely possible to find something that works for you though, so don’t give up. Try cutting the basal back earlier and let us know how it goes.
I also have a tough time exercising around 5 w/o eating anything. I haven’t bothered to figure it out since I usually exercise early AM or later in the evening.
I had the opposite effect with nph. By reducing the basal rate on your pump will help. My liver sometimes dumps sugars if I burn more than 1000 cal in a workout. So I will sometimes jump to over 300. I use a polar watch to see how many cal I am burning and I also use the CGMS. I hook my pump to my handle bars and see if I am am going low or high while I ride.
How long of tubing do you have?
I just did not find the CGM to be that accurate. I fought like crazy to get my insurance to pay for the CGM because of my problems with movement and exercise, but I just don’t trust it to be accurate.
The CGMS does show me when my bgs are falling or rising during the workout.
I have been biking on my stationary bike for now. But I had ankle surgery and I am 3 to 4 weeks away from biking again. I had an Osteochondritis dissecans . Surgery usually involves removing the loose fragment of cartilage and bone from the ankle joint and drilling small holes in the injured bone.