After successfully completing a couple of 5ks and a 10k this year, I received an email about a race series next summer - it’s 10k, 5k, 6k, and half marathon races, adding up to a marathon. I signed up 
I found the Hal Higdon plan and will probably use that next summer to train.
In the meanwhile, I just wanted to say thank you all for your help in the past, especially @Eric !!! I can’t believe I signed up…
I am excited for you! It’s gonna be great!
I used one of Hal’s program for my first Marathon. It’s super easy to follow.
It is not overly complicated with too many different types of runs or different speed work. Just consistent running that builds your base mileage. Follow the plan and you will get there, no problem!
While you can run a 5k or 10k without eating anything, one of the things about the longer distances is that you start getting to a point where consuming carbs during the race is very helpful. You can run out of fuel if you don’t eat, and that makes it so much harder.
Even the lower intensity use of fat metabolism is enhanced when you eat some carbs during a run.
For 5k’s and 10k’s, I only eat carbs if my BG is low and I need it for BG. But for 1/2’s and longer, I eat with the intention of knowing it will get me to the finish line faster and easier. There is a big difference there!
It would be super helpful to get started with your testing and fueling practice soon, because it’s just like training. The more you do it, the better you get at it.
I have made a bunch of wearable running BG meters, and have actually sent 5 of them to FUD members over the years. (Most recently to @needlesandmath.)
I’d love to get you hooked up with one. All I need to know is - what’s your favorite color?!? 
Sounds great, @allison ! I always like the Higdon plans. They’re simple, no-frills, and very customizable. Looking forward to the updates on your progress.
I’m so glad to hear your success in running and your dedication to it! Please keep us updated on your training and races!
Thanks!! I am taking it easy this week but will get back to it next week.
I know you do it differently (without a Tandem pump) - but was wondering what you’d recommend for me. Turning my pump off about an hour ahead of my workouts has been a game changer. I have been doing that, eating a granola bar, then working out - usually turning my pump on (with Control IQ off) about halfway through.
For a longer workout (I’m assuming 2.5 hours for a half), how do you recommend using my pump? I might just have to try and see what works but I’m afraid to leave it off too long.
And I truly appreciate the offer for a meter, but I really have had great success with my CGM. When I was testing for my previous thread, I just put my meter case in my fanny pack and that worked well!
Thanks! I had no idea where to start but I’ve seen his name a lot so figured it must be safe and effective 
haha!
It’s vitally important to fuel on the long runs. Yes, you can run 2 hours without fuel, but it makes the long runs more difficult.
It’s surprising how long you can do a zero basal when you are running! I have gone over 4 hours without basal, only taking boluses for fuel. And the boluses for fuel are small, like my I:C can be crazy, like 1:300 or 1:500 or even more. (Sometimes I can fuel without a bolus, even after zero basal for several hours.)
Tandem has a quick-bolus button that can be used. This would be a very simple trick!
The Tandem quick-bolus can be set to either units of insulin or grams of carbs. Before your run, you would change it to carbs.
When you have it set for carbs, the Tandem quick-bolus increment options are 2g, 5g, 10g, or 15g of carbs. I would suggest starting with 2g. Just as a starting point.
You can change your I:C and make it whatever you want if you need to. But you might not even need to change it.
Suppose your I:C is set to 1:20. If you have that I:C setting, and you have a 2g quick-bolus setting on your Tandem. When you hit the quick-bolus button, you would get a 0.10 unit bolus.
This is important - you are not actually taking only 2 grams of carbs. You would take something more like 20 grams of carbs! But you are only telling the pump it’s 2 grams, so you get a super tiny bolus.
After an hour of running - and while you are still running - what does 0.10 units and 20 grams of rapid carbs do for you? Let’s find out!
(I can tell you that those numbers would not cause me any problems. I might need to take a little more carbs, maybe less. But those numbers would not crush me. And I am speaking of rapid carbs here, like a running gel, not a granola bar.)
But regardless, you start with something in that ballpark and see if you need to adjust it after a few trials.
Since you can’t make your quick-bolus option less than 2 grams, if you need less insulin you could just adjust your I:C on the pump. Essentially, the combination of quick-bolus carb options and your ability to change your I:C makes it possible to use the quick-bolus button for whatever you want, very easily and quickly.
So the summary is that you would have zero basal going for your entire long run, and try to fuel during the run with very small boluses and carbs.
Does all of that make sense?
Other notes:
(Yes, you can do it without the quick-bolus button, just using the normal pump interface. But I think touch-screens suck when running! Why not use the quick-bolus feature?)
(Some of this whole idea came to me when I was exploring other pump options after Omnipod abandoned their old PDM (push-button) and went to only touch-screen options. I knew that would not work for me, so I looked into Tandem as an option. I got a little insight from @elver about it too!)
Thanks for your thorough reply! Yes, that makes sense. We are back to more trial and error again - but when I did the testing for the 10k, it was easier to figure out than I had expected. So hopefully it will be the same for the half. I will definitely try to run that 13.1 miles before the race in August!
I currently use the quick bolus button all the time - I have it set for 0.5 units. Maybe I’ll give that a try (using carbs instead of units) once I get into longer distances.
I think I’ll continue running and see how far I can go and feel good on zero basal. I did 7.5 miles this past Sunday (new personal record!) and ate a couple of gummy worms along the way. No problems
@allison
That sounds great! Congrats on the 7.5 miles! 
Since you are already using the quick-bolus button, that makes it super easy. I really thought it was cool that you could adjust it for carbs, so it could be a very tiny bolus.
Just as a reference from my personal history with all of this - when I first started, I only used insulin when my BG was high, and I only took carbs when my BG was low.
That seems incredibly simple and common sense, right? Duh, you take insulin when high and carbs when low.
BUT… I started to learn more about fueling and performance, and I learned that carbs are not just for low BG, they should also be used to fuel the activity. At that point I started taking insulin so that I could be able to take carbs. Like even if my BG was fine, I would take insulin and carbs.
None of this is required. You can certainly run a 1/2 without any fueling. But I’m just saying that carbs will help you get faster for those longer runs.
This is just to show you the math of carbs vs fat. If you google Respiratory Exchange Ratio (RER) you will see this. The RER is higher when we are running faster (it means we are consuming more oxygen and creating more carbon dioxide).
Look how carbs become more predominant the faster we go (the higher our RER gets):
Why am I saying all of this? Just to emphasize the importance carbs can play in exercise, and how it helps to start practicing it!
I always wanted to do a half marathon but hip issues ended my running. I did many 5k and 10-12 ks but no matter how I planned and practiced on race day I ended up in the 200s.
I was always afraid to take more than my regular training insulin dose for fear something would change and I would go low. But the adrenaline/cortisol spike was always there. This was prior to Dexcom so maybe things would be different now.
I never could run very far before I had a CGM! It is truly a game-changer!