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Marathon

Hi @RAM1306 and welcome to the forum.
Are you asking about a particular marathon, or a competitive marathon in general, or just completing the marathon distance in the allowed time?

Several Type 1 diabetics on a keto/low carb way of eating have taken part in long distance evens while running in a fasted state. Dr Ian Lake a T1D has done at least one (monitored) fasted 100miles in less than 5 days run/walk event. He has also recently been cycling from UK to Switzerland on 30gms of carbs per day and has completed nearly1000 miles in keto/low carb state and posting his progress on Twitter.

Links:
100miles in 5 days: https://www.diabetes.co.uk/forum/threads/zero-calories-5day-100miles-experiment.177033/

Cycling UK to Switzerland on 30gms carbs per day (on X/Twitter): https://x.com/idlake
 
I should point out that those Type 1 diabetics did prepare for those long distance feats especially eating low carb/keto for long enough to become 'fat adapted'.
They just did those things in order to show that it isn't inherently dangerous for diabetics, even a T1D to exercise in a state of nutritional ketosis.
 
Whilst I have not run a marathon, I know others with Type 1 who have and can confirm that a keto/low carb maybe one possible approach but it is definitely not the only one.

My long distance exploits are either walking or cycling and I eat a "normal" level of carbs. It has become easier to maintain my BG throughout these exploits since I started using an insulin pump but I was able to do so previously on MDI. May key "trick' was to put some very diluted fruit juice in my water so I was taking on carbs most of the time rather than bulking up on a banana, for example, as my BG started to drop.
 
Hello @RAM1306

Yes have done 3 now, I do the London virtual marathons, but plan my own routes and have a couple I use, I use a tandem slim pump and will start with levels 10mmol/l+ and I turn off my basal 2 hours beforehand, if still running high after 2 hours I do a correction, but I tend to stay fairly highish running at a moderately slow pace, it's when I hit hills that my levels can drop as muscles deplete glucose quite quickly, so have to top up with jelly babies/beans and cereal bars/flapjacks, I don't use glucose gels as they give me a poorly tum, and then a really careful watch over the next couple of days as the muscle repair works start, I run 2-3 times a week and will do a marathon once a year and then mostly 5 & 10k's and the odd half marathon.
 
Thanks for your replies. I am on a Medtronic insulin pump and guardian 4 sensor. My problem is with running 5k my sugars really drop to below 3. I do eat skittles to boost it but it is not maintained for long and didn’t want to increase my distance if this is happening. I currently run three times a week and have entered for the Brighton Marathon.

Just looking for suggestions to keep my sugars at a constant level.
 
There is a film called “Run on Fat” which describes becoming fat adapted to run long distance. The full movie is available on the dietdoctor.com with the first 6 minutes on this YouTube video …

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RAM1306 said:
Thanks for your replies. I am on a Medtronic insulin pump and guardian 4 sensor. My problem is with running 5k my sugars really drop to below 3. I do eat skittles to boost it but it is not maintained for long and didn’t want to increase my distance if this is happening. I currently run three times a week and have entered for the Brighton Marathon.

Just looking for suggestions to keep my sugars at a constant level.
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I aim to start at 10mmol/l but below 13, with no fast acting insulin on board, for a 5k that works and I have no issues with hypos, but also in exercise mode. It also depends on time of day and temperature as both these also affect me, so the warmer it is the quicker I can go hypo, and I can generally run in the morning without dropping but later in the day I have to keep a close eye on levels, I tend to start taking glucose on board when levels start dropping below 6mmol/l too as can drop quickly from 6.

If still going low then set up a new basal profile with a 30-40% rate.

You can do it just trial and error and don’t feel defeated with hypos - I ran last night in a trial run over 2 big hills 4.7 miles and started dropping around 3.5 miles in but didn’t get my starting BG level and was below 9, I know this was the reason along with some residual quick acting on board, I managed to run to the end with levels between 3.2-3.6 and felt cracked at the end but it doesn’t ever put me off as I know what I’d do differently next time.
 
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Art Of Flowers said:
There is a film called “Run on Fat” which describes becoming fat adapted to run long distance. The full movie is available on the dietdoctor.com with the first 6 minutes on this YouTube video …
Click to expand...
It’s an interesting train of thought but for insulin dependent diabetics the use of carbs not just for fuel but for hypos is vital so the philosophy of running on fat isn’t ideal - it’s more so balance with diet and with managing BG levels too.
 
I have a completely different problem with running. Parkrun 5k always puts my BG up. I like to start at less than 5 and usually finish, about 23 minutes later at about 11 to 13. 10k similarly puts my BG up particularly if I am trying hard. Last half marathon I had nothing to eat. Really should be able to use glycogen stored in liver and muscles for about 2 hours of exercise.
Never done a marathon but I always find when I ride my bike for more than a few hours I need less insulin and much more food.
Experiment!
 
RAM1306 said:
Has any one with type 1 diabetes done the marathon and what their sugar levels were like
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Hi,

I've done the Yorkshire Marathon twice with varying results in blood sugars.

At the beginning of the race I aimed for slightly higher than target range, but this is usually the case with the inclusion of nerves and excitement.

Attempting the first marathon I used a bag and checked my levels, administering a small amount of insulin if it had spiked too high (I only did this once and the unit was low) I consumed around a gel or chew (SIS Beta fuel worked really well for me) per hour. My blood sugar level was stable throughout but that was probably because I wasn't putting my all in. I finished in 4.10.

The second time I moved over to Omnipod with a Dexcom, I assumed my control would have been better. However, I was so determined to avoid low blood sugar in the last six miles I sent them sky-high, which didn't help. Another thing to mention would be stomach issues during the race, towards the end of the second time I had consumed too much, with high blood sugar and this made it uncomfortable to run. I finished in 3.40.

Depending on what you use to control your diabetes, it can be made easier but it's just another thing to think about when running.

I would always carry way more than you need as a precaution. One time I was fading and had to rely on spectators' sweets at the side of the road.

Doing long runs as a practice where time isn't as important, trying out the nutrition you would use is a good idea too. I find that gels don't spike my sugars quickly enough to prevent a hypo.
 
Fern Hopper said:
I have a completely different problem with running. Parkrun 5k always puts my BG up. I like to start at less than 5 and usually finish, about 23 minutes later at about 11 to 13. 10k similarly puts my BG up particularly if I am trying hard.
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Have mentioned in your other thread that it's the adrenaline/cortisol pushing your BG levels up as you do run hard, your liver is giving you an extra boost to help you get going, perhaps try a much slower gentler pace as a one off to see the difference ? I sometimes run hard and go high and stay high for anything up to 3-4 hours afterwards but a slower pace keeps me in range.
 
JGibbons said:
Doing long runs as a practice where time isn't as important, trying out the nutrition you would use is a good idea too. I find that gels don't spike my sugars quickly enough to prevent a hypo.
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Definitely try this as getting the fuel source right is vital, I set my target at 6 mmol/l on long runs and start fuelling at this point as I can drop quickly from 6 to hypo and particularly when using a sensor as it's reading is 15-20 mins behind anyway so a good buffer is helpful, also I find once I go hypo that I can't get my levels up very quickly at all and have to walk and fuel but it does take the wind out of your sails too when that happens so avoidance at all costs is best.
 
Juicyj said:
Have mentioned in your other thread that it's the adrenaline/cortisol pushing your BG levels up as you do run hard, your liver is giving you an extra boost to help you get going, perhaps try a much slower gentler pace as a one off to see the difference ? I sometimes run hard and go high and stay high for anything up to 3-4 hours afterwards but a slower pace keeps me in range.
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I ran much slower last weekend and BG didn't spike. Running tonight might prove to be a bit of a puzzle as it's efforts of some description.
But I recover from a spike fairly quickly - quite often within an hour. Then I can eat something sticky and delicious! Croissant, fruit, quark and nuts for preference. There has to be some compensations in life!
Scan yesterday. My watch told me I was stressed. Really?
 
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