Ultramarathon nutrition for type 1 diabetics

This post is long overdue and has just been written on a long haul flight to the US. It needs mention of Babybel cheeses and hydration but other than that, I think it should be helpful to type 1 diabetics wondering how to approach long runs. Bulletpoint: condition yourself to do more with less.

There is a fascinating discussion finally taking place around what we – ‘we’, as in ‘everyone in the developed world’ – treat as nutrition. Having just watched That Sugar Film I think there is a chicken or the egg discussion to be had around whether that film started the wave or has jumped on the crest. One thing is sure, though, a number of lifestyle writers and blog-based journalists have been inspired by its content, even if they are now writing without acknowledging it as a source.

So, to my point: race nutrition for type 1 diabetic ultramarathon runners.

Niche huh? And what the f&%# does that have to do with the unfolding mainstream discussion around calorie sources as a contributor to health problems, rather than the chronically simplified discussion around calories in, and calories out?

Simply this: whether you are diabetic and running for 30 hours or not diabetic and simply running for 15 hours, it is not just what you do on race day, in a nutritional sense, that matters. There is a whole of life approach, or at the very least a dedicated period of time for tuning the body, that will contribute to how well your body works on race day, based on what fuels you throw into it.

Like running shoes, nutritional approaches vary widely. I am writing from my own experience as a type 1 diabetic, having completed multiple 100km runs on track, road, and trail. My quickest so far was just over 11 hours on a relatively flat course, so I have not yet run 100km as fast as I would like to. At the other end of the spectrum, I’ve been fortunate enough to run 4 250km multiday events, and 3 single stage races of 240km and up, as well as a couple of 100-milers.

This means that I’ve had some great opportunities to get things wrong – both diabetically and nutritionally – and to try some ideas with the intention of getting closer to doing things right.

And aside from some additional nuggets of wisdom you might harvest in the next page or two, know this: nutrition isn’t just something you do on race day.

My first time running Coast2Kosci – other than having been in Antarctica the week before to run just over 140km with Team Born To Run – my blood sugar management was shabby and my nutrition was all over the place. My sugars sat above 12mmol/L for more than half of the 38+ hours I was on course simply because I was more anxious about running into hypo territory than on high sugars.

This was because I didn’t yet understand how deeply sustained high sugars – in my terms, over 10mmol/L for 90+ minutes – will affect the body. Nausea, sluggish performance, impaired endurance – these will come eventually. They do not occur immediately, as clear markers of a hypo will, but after a period of 4-8 hours. To reduce the concentration of sugars throughout the body – as I understand it, at least – fluid is drawn from whatever sources are available, and ultimately this will have the knock-on effect of impaired organ function.

Simple lesson: Don’t sit high for too long.

Simple problem: But what if, as a diabetic athlete, you’re scared of low sugars on race day?

Simple answer, and simple question: what makes your sugars fluctuate wildly?

There are three key variables at play for the diabetic endurance athlete, as I see it.

1. Exertion: The harder you’re exerting yourself, once beyond that first hour or so where adrenalin is playing a massive part by blocking the blood-sugar-lowering action of insulin, the greater an effect your insulin-on-board is having in pulling your sugars down.
2. Insulin on board: This consideration must include both basal levels, whether by pump or longer-acting insulins like Lantus and Levemir, and recently administered boluses and corrections.
3. CHO inputs: This is as basic as it gets – how much carbohydrate have you had within your window of action and beyond? If insulin functions in your system for 2-3 hours, how is it interacting with sugar levels and carb intake from four hours ago, or from 10 minutes ago.

Rather than going straight to advanced level factoids like:

• caffeine will accelerate uptake of carbohydrate and thereby lowering of blood sugar
• sugar levels will drop faster at 7 hours into a run than at 2 hours into a run, all other factors being equal
• sugar levels will respond differently before dawn than at, for example, lunchtime, but possibly as a function of reduced pace as the night ends rather than simply as a result of ‘dawn phenomenon’
• inflammation in the body may well be a factor that increases insulin resistance as a long long run (20+ hours) progresses

Let’s look at the basic relationship here: Exertion – IOB – CHO

Carbohydrate releases glucose which is burnt in cells as a fuel, having crossed cell walls thanks to insulin, thereby enabling desired levels of exertion.

But even simple factors like map reading will accelerate blood sugar consumption, as a direct consequence of the brain’s voracious appetite.

So how do you, a type 1 diabetic ultramarathoner, manage sustained effort across varied terrain at all hours of the day and night?

The cop-out answer is: only you can answer that.

The realistic answer is: practise, practise, practise.

Have enough safety strategies to train hard enough to make mistakes, and then fine tune.

If you can run at the effort you want to for 5 hours with your basal insulin set to, say, 40% with very few corrective boluses, and consume an energy source that works for you – job done.

But if you give that a try and find you go too high and have to really correct, or go too low and then have to smash food, wobble through weakness, then deal with sloshy guts and nausea, then don’t be discouraged – this is where practise begins.

My answer?

1. Daily life approach pre-race. You might be running for one weekend, but your nutrition preparation can begin at least 3 months out. My preferred option is to optimise fat metabolism with a reduced carb intake, both in general life day-to-day and in training.
2. Reduced carb dependency on race day. By more effectively burning stored fuels, I am less dependent on a constant intake that can lead to nausea. It’s mostly subjective, but I feel now that I function better on 30-60g CHO/hr with intermittent periods of higher intake than when I felt like I needed to take in 75-100g/hr just to keep moving forward.
3. Stick to what works for you on race day. When presented with a variety of tasty and colourful options after you’ve already been running for 8 hours and there are at least 20 to go, it’s easy to rationalise eating some or all of them. But digestively, opposing foods can go to war with each other. Foods you don’t normally race on might confuse your digestion under exertion. And quantity especially becomes a factor. The difference between drinking 100mL of a fluid and running, as opposed to 250mL, or eating half of something rather than all of it, can be huge, and comes back to self-discipline. Don’t see the pleasure of a favourite chocolate bar or drink or snack, consider the nausea and discomfort you have put yourself through previously, making the same impulsive mistake. Rewrite that nauseous history.

Eating on race day in an ultra is NOT meant to be a mobile reconstruction of the MasterChef desserts showdown. Forget gourmet, you want function. The less you have to fuel and the more stable all of your inputs and outputs – exertion, IOB, CHO – the less effort you have to put into your fourth major determinant of success: ADAPTATION. Screwing up in training is great because it forces you to build your ADAPTATION and COPING muscles. But it’s easier to save this effort for running on race day, if you have created that option for yourself in TRAINING.

Rant over. Do with that what you will.

What I do is this:

Concentrated Tailwind from an Ultimate Direction soft flask. I mix Naked flavour to a concentration roughly 4 times what is recommended and I sip on 400-500mL for a 3-4 hour period of running with small rinses of fresh water after most mouthfuls. Less carb intake also reduces need for hydration as carbohydrate metabolism is water-intensive. Tailwind is about 90% of my total energy intake for running (or riding) long.

Occasional purpose specific gels/blocks. Roctane seems to work well for me. I generally use the non-caffeinated flavours because all I am after is 20+g quick carb and the proprietary blend of amino acids which GU and my body seem to think enhance metabolic energy efficiency. I also use Clif Bloks for either increasing electrolyte intake or caffeine intake or some variety of carb source if I feel like chomping on something and then hitting it with water.

Caffeine. Despite what a podiatrist once told me, I believe caffeine fasting for a week or more makes a massive difference to how the caffeine works in the body. Stay away from it until about 10pm on race day too if you can, although a morning cuppa will work wonders, especially before you leave your rented accommodation for the land of roadside stops and port-a-loos.

Most of this is advice that non-pancreatically-challenged ultra folk will also find helpful.

If you won the autoimmune lottery, you should also know that this is all in your hands. At the end of the day, for all its predictable unpredictability type 1 diabetes has some simple rules, whether on the run or not.

1. Sugars within a range that YOU determine are awesome. 5.0-11.0 is a perfectly functional place to be when kicking your own ass and heaving like a beast. Ignore any DE who tries to tell you otherwise, especially if they’re overweight. Don’t trust bald hairdressers either.
2. Rapidly descending sugars need attention. Rapidly climbing sugars might just need you to run harder. ‘Attention’ doesn’t need you to stop, or even slow down much. Pound more carbs than you had planned to, maybe check your IOB and think about your short-term management plan for the next hour or so, and run on.
3. Listen to your body, learn from your mistakes, do it better next time.
4. Seriously, what’s the worst that can happen?

And I must say I’m feeling pretty drawn to the diet that someone mentioned a few weeks ago – JERF. Just Eat Real Food.

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