Info sought by runner

Hello–I am new to this site, but find it helpful. I am training for a marathon this October, it will be my third, but my first since employing very strict control about 20 years ago. Of course, my biggest challenge is keeping BG high enouigh when running long distances. If anyone out there still takes injections, as I do, I would love to know types of insulin, dosages and times, and diet as relating to long runs. For me, up to eight miles is OK, never easy, but do-able, beyond that, a much greater challenge. I have been Type 1 for 41 years, a runner and cyclist most of that time, and I may have info of help to you??? Thanks, Howard.

Welcome Howard.

I switched to a pump last year for the very reason that I found BG management hard on injections. As my distances increased, it was harder to keep the BG under control with injections. Here’s a few suggestions that I’ve discovered from my own experimentation.

  1. If you take 1 injection of slow acting insulin (e.g. Lantus) each day, you might want to split that into 2 injections. On days with a long run you could reduce 1 of those injections (maybe 25%) to lower your background insulin level during the run.

  2. I’ve found that 25 g of carbs every 25 - 30 minutes helps keep a fairly stable BG level throughout a run. I like the GU brand gel as it’s digested quickly and actually tastes pretty good.

  3. Post run I need additional insulin. With a pump I generally push a few buttons to deliver an extra 1 - 1.5 units, you’d have to take an extra injection of fast acting insulin. The reason for this is that the muscles are releasing glycogen into the blood system during the run. And apparently that process doesn’t stop as soon as the run is over. So I’d often experience huge BG spikes after a run.

I hope this helps in some little way.
I’m running my first 1/2 marathon next month.

Hello Ken, thanks for answering. I do use Lantus for background, currently 14 units every morning. I did try splitting dose when I began using Lantus, did not notice any difference at all. Experimenting w/Lantus does is now focus of fine tuning insulin to cover long runs. As I increased time running to 2:30, and experienced frequent lows, I tried lowering that dose, but found any lower than 12 or 13, I did not have the energy needed, regardless of diet. I believe no matter what the other variables, there needs, at least in my body, to be enough insulin to metabolize sugars, be they from food ingested, glycogen stores, or fat stores. My intake of carbs varies quite a bit while running–many variables, such as intensity of workout or how hard I worked out previous day. But your suggestion of carb intake is about right for me. I currently have five months to go before marathon, and my long runs are about 2:30 in the hills–last Sunday I did a half marathon in 2:07 and was pleased–I have never been fast, and I am now 54 years old–but I felt as good as can be when pushing hard. My goal for the marathon is 4:30, and I feel I am on track for that–it will be a trail marathon and a bit slower than road running, but I try not to dwell too much on time, tho am competitive by nature. I absolutely hate being passed. I try to begin long runs around 160 BG, then try to keep it there–I check BG about every 2 miles during a long run==I suffer from hypoglycemic unawareness, esp. during a long run when fatigue is an issue. I like hard candies–nothing in stomach at all–sugars assimilated through saliva. In a race, I have easy access to ERG. I carry OJ and raisens in fanny pack for the real lows, but of course try to avoid them. A lot of people swear by GU, and I will experiment. No trouble w/post run highs, the opposite is true for me–I tend to be low for 16 or so hours post long run. So there you have it, maybe more than you cared to know, maybe not, but thanks again for listening. Sounds like you used Lantus in your pre-pump days, and am very curious re: your doses. Howard.

If memory serves we well I was on around 18 U Lantus in my pre-pump days.

I’m not fast either, hoping for a 2:15 on my first 1/2 next month. I did a 10K last weekend and my BG was high (200 - 240) much of the run. It was very unpleasant as I felt a need to pee and drink the entire time. It came down by the middle and I did take 1 GU at mile 5. Though it was my PB (1:00:15) I’m pretty sure I would have been 2 - 3 minutes faster if my BG were under control (as training runs of that distance are generally under an hour without excessive effort).

I’m very fortunate in that I have a CGMS. So I can look down any time and see pretty close what my BG was 15 minutes earlier without any finger pricks. When I see it starting to drop, that’s when I know it’s about time for another GU. On a good training run I’m usually able to keep BG between about 90 and 140 the entire time. It took a lot of experimentation though to get that good of control.
Good luck,