Any tips for half marathon training?

nicki92

Active Member
Messages
41
Type of diabetes
Type 1
Treatment type
Insulin
Hi,

I was diagnosed with type 1 at the end of September, so everything is still pretty new. I've run the half marathon distance once before (pre-diabetes) and am now training for my first HM race in April. I haven't had any problems with blood sugar levels during ~5K runs, but yesterday I went for my first longer run of ~12km.
My levels were 8.2 when I set out, more than two hours post a small meal (so insulin shouldn't have been in my system) and after half an hour down to 5.5 and trending downwards. I had an energy gel (25g carbs) and monitored for the rest of the run. My level went down to 5 (according to Libre; 4ish on xDrip) and stayed there for the rest of the run - another half an hour. I had maybe another 10g carbs during that time. After getting home it went back up to 9-ish before decreasing again. Then overnight I had hypo alarms and ate some carbs at 2:30 and again at 5:30.

What I would mostly like to understand is
* whether it's safe to keep running at 4-5mmol -- it stayed stable and another energy gel would have seemed like a LOT
* what I should/could do differently to avoid the overnight hypos
* just generally if anyone has tips or experiences to share! My runs are (hopefully) going to increase in length from now until the Spring and I want to be able to manage my diabetes at the same time!
 

In Response

Well-Known Member
Messages
3,371
Type of diabetes
Type 1
Treatment type
Pump
- it is not unsafe to exercise at 4 to 5mmol/l if it stays stable. However, you are more at risk of going hypo so it is not recommended
- I would always reduce my basal for the day after exercise. This depends on your basal as Tresiba is very long lasting and any changes can take 3 or 4 days to take effect. If you are using Tresiba, it may be beneficial to request a twice daily basal such as Levemir which provides more flexibility
- one tip I was given for exercise and lowering levels is to add something sweet to my water bottle - a very dilute fruit squash or fruit juice so maintain levels rather
than letting them drop
 
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Trevor vP

Well-Known Member
Messages
85
Type of diabetes
Type 1
Treatment type
Insulin
Hi,

I was diagnosed with type 1 at the end of September, so everything is still pretty new. I've run the half marathon distance once before (pre-diabetes) and am now training for my first HM race in April. I haven't had any problems with blood sugar levels during ~5K runs, but yesterday I went for my first longer run of ~12km.
My levels were 8.2 when I set out, more than two hours post a small meal (so insulin shouldn't have been in my system) and after half an hour down to 5.5 and trending downwards. I had an energy gel (25g carbs) and monitored for the rest of the run. My level went down to 5 (according to Libre; 4ish on xDrip) and stayed there for the rest of the run - another half an hour. I had maybe another 10g carbs during that time. After getting home it went back up to 9-ish before decreasing again. Then overnight I had hypo alarms and ate some carbs at 2:30 and again at 5:30.

What I would mostly like to understand is
* whether it's safe to keep running at 4-5mmol -- it stayed stable and another energy gel would have seemed like a LOT
* what I should/could do differently to avoid the overnight hypos
* just generally if anyone has tips or experiences to share! My runs are (hopefully) going to increase in length from now until the Spring and I want to be able to manage my diabetes at the same time!
If I eat before training I reduce my fast acting Insulin by circa 30% for a 80% of Heart Rate 1 Hour session bike or run and by about 45% for anything harder for 1 hour. Also should I eat / inject after training I reduce my fast acting by 15%.
Try keep Carbs low in meal to also have as little possible quantity IOB and always carry a belt with 10 Jelly babies. Sometimes just need one at 25 mins in if I got the Carb insulin timing wrong and also just watch my pace. Also can drop to Z2 so as not burning Carbs to let insulin/carb balance catchup. I use the same method in training as in long endurance events, small numbers Carbs and Insulin means small mistakes

best wishes and hope this helps
 

nicki92

Active Member
Messages
41
Type of diabetes
Type 1
Treatment type
Insulin
If I eat before training I reduce my fast acting Insulin by circa 30% for a 80% of Heart Rate 1 Hour session bike or run and by about 45% for anything harder for 1 hour. Also should I eat / inject after training I reduce my fast acting by 15%.
Try keep Carbs low in meal to also have as little possible quantity IOB and always carry a belt with 10 Jelly babies. Sometimes just need one at 25 mins in if I got the Carb insulin timing wrong and also just watch my pace. Also can drop to Z2 so as not burning Carbs to let insulin/carb balance catchup. I use the same method in training as in long endurance events, small numbers Carbs and Insulin means small mistakes

best wishes and hope this helps

Thank you Trevor that's really useful!

I had another experience today: before eating my BG was quite low, so for 30g carbs I'd normally take 1.5IE, but didn't take any (I also ate a fair amount of fat). An hour later my BG was rising rapidly so I had 0.5 insulin units. Two hours later I went for my run, heading out with BG of around 9mmol/l, and it stayed between 8 and 9 for the whole run! I had sweets and a gel and didn't need anything!
(I assume my body should be done with such a small amount of insulin after 2 hours and I was happy to be under 10 but still high enough to feel safe heading out to exercise.)

I guess maybe there's something in the difference between the two runs or what I ate but it's so strange to me how my body can react so differently to very similar exercise. I suppose I'll learn it all in time, but for now I reeeally appreciate the tips. For now I will definitely remember lower carbs/low insulin amounts before exercise -- thank you for your wisdom!
 
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nicki92

Active Member
Messages
41
Type of diabetes
Type 1
Treatment type
Insulin
- it is not unsafe to exercise at 4 to 5mmol/l if it stays stable. However, you are more at risk of going hypo so it is not recommended
- I would always reduce my basal for the day after exercise. This depends on your basal as Tresiba is very long lasting and any changes can take 3 or 4 days to take effect. If you are using Tresiba, it may be beneficial to request a twice daily basal such as Levemir which provides more flexibility
- one tip I was given for exercise and lowering levels is to add something sweet to my water bottle - a very dilute fruit squash or fruit juice so maintain levels rather
than letting them drop

Thank you for this advice! I will mention my training to my diabetes doctor -- I am currently on Tresiba and honestly would much rather not have to inject even more frequently, but will see what they recommend. I also appreciate with Tresiba that (for me at least) it doesn't seem to have any detrimental effect if my injection times vary by a couple of hours, so I do like that. I also appreciate that half-marathon training might mean some adjustments are necessary, so I'll have to ask what they think.

I've promised my sister to enter (the ballot for) a marathon at the end of 2023, hoping I might be hooked up to a pump by then to make things that much easier!
 

bmtest

Well-Known Member
Messages
141
Practise makes perfect in sport with diabetes. So train for the specific times you may have to run a half marathon. For me when I did run half marathon I used a combination of less insulin and a few extra carbs before run.

On the run I would always drink one bottle of lucozade sport which I carried. Back up packet of dextrosol rarely used. I carried no testing equipment and after run with club ran 2 mile home

What happens your body gets used to this activity just like going off to work it's no different. If you are not used to it yes you will receive lows following run as expected.

Aim for static blood sugar reading i.e not dropping one where if you don't do any activity it will rise.
 
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