Tandem tslim exercise mode

Hello! I have been using the Tandem tslim x2 with ciq for several months. I have gotten my settings (mostly) in a good place but I am having trouble with exercise.

It seems to me that “exercise mode” does not do anything. I go low almost any time I exercise- even if it is leisurely exercise (such as walking the dog on a day in which he wants to stop and sniff everything) and also even if I put exercise mode on a half an hour before I start. The only time I can avoid lows is when I exercise first thing in the morning, presumably because the exercise is combating against FOTF.

Any suggestions/advice on how to make exercise mode work better for me?


I eat a banana before exercising. Or under-dose for a meal (as in: tell my pump I’m having 30 g of carbs when I’m actually having 40) and then exercise before it shoots up.
I was told to set it to exercise mode an hour or even two before starting exercise mode but that’s just crazy talk.

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Also, I often have to snack.

Exercise mode doesn’t do anything for me either. I make sure that I don’t have any IOB before starting exercise and carry a hypo treat.

I agree. The other issue is it gives automatic correction boluses when in exercise mode. In my opinion that is dangerous and an absolute terrible design by tandemn.

So taking fast acting carbs while exercising results in my CGM showing a fast rise in BG, but I know this is a temporary rise and my BG will come back to normal range. I think that is a pretty common BG response to carbs while exercising. Unfortunately your predicted future bg will calculate a required bolus and automatically give. The is the absolute last thing I want is a bolus and creates a big problem.

So temp basil is still the best solution for exercise.

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I’m surprised this game been mentioned yet. I have three commonly used basal profiles. "Control-Iq"is my standard, “Low_iq” is 50% of my standard, and “High_iq” is 150% of my standard.

Part of getting ready for high activity is “getting stupid”, as we call it in this house, which means switching to the “low_iq” profile. (Hey, it makes me laugh.). As well as switching over you the exercise activity.

That can handle basic exercise and general physical labor on the farm for me, but all Control-IQ can do is withhold your insulin. It can’t overcome basic physiology. If you’re burning up more carbs then you have on board, and your basal delivery is fully suspended, then you’re going to have to eat some more. Usually you only burn carbs hard for the first 15-20 minutes of exercise, after that you’re supposed to fuel with fat instead, hence the “second wind” effect. Might also be why I don’t have a massive problem, because I’m usually going into exercise after a meal, so there’s enough carb on board to get me through those first minutes.

Also remember that correction factor is critical to how Control-Iq works. Too high of a number here, and you cripple the system. It is incapable of intervening, and your stuck in whatever direction you’re headed. If you’re going low and Control-IQ is still delivering basal, then this might be a factor.
Too low of a number here, and you get the crazy roller coaster of highs and lows. It both withholds too much insulin when you’re low, resulting in a rebound high, AND gives too much correction insulin when you’re high, resulting in a rebound low.


I also have profiles for exercising. I use one called hike, and one called extreme. 25% reduction and 50% reduction. Both also run the exercise mode, but I think the exercise mode just adjusts your ranges a little. By itself it’s useless.

I like the bolus correction in exercise mode because when I exercise I get a spike before I start to go low.

I use carb gel. I eat one after 20 min then another for each 30 min that I’m still going. I use the ones meant for athletes. Flavored like coffee or vanilla. Not the red cough syrup tasting ones from the pharmacy meant for diabetics with no ability to taste. https://res.cloudinary.com/shogun-frontend/image/fetch/f_auto,q_auto,c_fill,w_1080,h_1080/https://f.shgcdn.com/832c348a-0f53-4da8-a943-1b1d5a007765/

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Thanks. I had started using temp basals similar to @Jim26 , but creating another profile makes sense. I hadn’t thought of that - I guess I’m still thinking in Medtronic mode.

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I got tired of trying to get exercise mode to work for me. As a result, when doing dog walking up to real work like chainsawing a tree or such, I take one lemon sour piece of candy. It is only 4g of sugar and it keeps me from going too low. I don’t recall ever going high on one lemon sour. If my activity out lasts the candy, I simply take another one.



It doesn’t always work well for me either but I have more success when I start the exercise profile at least an hour before I head out for my long walk. I do usually eat my prunes while walking(yes, I am getting old!) I don’t take insulin for them on my long walk but take half the amount on shorter walks.
As with everything diabetes, trial and error! Good luck!

I hate exercise mode because it gives automatic boluses over 150 or something like that, which are then amplified because of the exercise you’re doing. I always leave my pump in sleep mode (24/7) and I avoid exercise if I’ve recently taken a big bolus. Usually I work out in the morning, so I have a nice flat line from overnight, then I eat a SMALL snack and turn the delivery off until I’m about halfway through my workout, then turn it on again. That seems to work pretty well for me.