T2 cycling 100 miles in a day, how to fuel?

Convert your metabolism to running on fat, if possible.

I haven't reached the ability to cycle 100 miles non stop (but I'm working on it).

I can do 50k (around 35 miles) on just a cup of coffee with butter and double cream and I am usually in ketosis.

A fellow rider (non-diabetic) who took up the keto diet for health and weight loss reasons cycles on just a double espresso. Must try that sometime. Possibly.

A good read is https://www.amazon.co.uk/Art-Science-Low-Carbohydrate-Performance/dp/0983490716 (other bookshops are available) which explains about "hitting the wall" if you are fuelled by carbohydrates and how this should not happen if you are fuelled by fat.

The other thing to watch for is pushing a little too hard. I was reading about training/performance zones and that if you push yourself from fat burning to anaerobic zones you can crash and burn. Perhaps you just need to ease back a small amount to manage long distance cruising?

Edit: https://bengreenfieldfitness.com/ar...ic-diet-articles/ketogenic-diet-for-athletes/ looks interesting. Just reading it so I can't recommend (or not) yet.

A lot of endurance athletes are now turning to ketogenic eating in order to avoid your exact problem. If you become fat adapted then "The Wall' becomes a thing of the past as you will be carrying thousands of calories of energy in your body fat which you can access. Most then do their endurance trials in a fasted state using the doughnuts they ate years ago for their fuel.

bulkbiker said:

A lot of endurance athletes are now turning to ketogenic eating in order to avoid your exact problem. If you become fat adapted then "The Wall' becomes a thing of the past as you will be carrying thousands of calories of energy in your body fat which you can access. Most then do their endurance trials in a fasted state using the doughnuts they ate years ago for their fuel.

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Interesting thread as this would apply to cyclists I know seeking these same answers Neither of them have any spare body fat though. So if they became fat adapted what would they burn in the lack of years old donuts and carbs?

HSSS said:

Interesting thread as this would apply to cyclists I know seeking these same answers Neither of them have any spare body fat though. So if they became fat adapted what would they burn in the lack of years old donuts and carbs?

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We all carry about 40k calories in body fat even the skinny ones..when you are obese I think I heard that the figure was up to 400k calories... so I reckon that should fuel one race ok.. but you do have to be fat adapted to access it or your glucose stores get emptied and "The Wall" hits like a ton of bricks...

I used to cycle competitively and “the knock” was a real danger when out training. If you hit the wall and had no food with you it was debilitating, bad enough to prevent you cycling to a shop. Quite preposterous really when the body has several thousand calories waiting in cold storage.

Coincidentally I’ve recently been considering buying a new bike. If I do so, it will be interesting exploring riding again in ketosis.

Jim Lahey said:

I used to cycle competitively and “the knock” was a real danger when out training. If you hit the wall and had no food with you it was debilitating, bad enough to prevent you cycling to a shop. Quite preposterous really when the body has several thousand calories waiting in cold storage.

Coincidentally I’ve recently been considering buying a new bike. If I do so, it will be interesting exploring riding again in ketosis.

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Go for it! One of the best exercises around.
I've recently had some glorious rides in sunshine and a 2C temperature.

My plans are for cycle touring (never did any sport competitively) but I am, hoping that I can plug along all day burning fat.

Out of training at the moment but can manage 25 miles.

Pulling together various threads and ideas, I wonder if the chocolate truffles would be a suitable fuel for an extended cycle ride?

Lots of fat, a little bit of protein, not a lot of carbohydrate.

However I know that it takes a while for glucose to get to the tissues if you are exercising hard (hence not being able to stave off the wall even if you are snarfing down glucose gels) so I don't know how quickly fats get through the gut and into the blood stream and available for use.

Anyway, I will do a few minor experiments,

I have no idea how to measure if I am running out of metabolic ketones in my muscles because there must be a maximum rate that body fat can be re-purposed for fuel.

There must also be a point where gluconeogenesis can't keep up with the very limited demand for glucose during extreme exercise.

I wonder if there is a study.......

I'm a relatively recent Type 1 LADA diabetic, in my honeymoon period, and not yet taking Insulin. So I don't know a lot about Diabetes. But I do know a lot about my body and how it works for me. Having ridden 100 miles today and 300 miles this week I can share what I've learnt for me

Like you pre diagnosis and early days, I struggled with energy, especially if I had to push hard. It felt like the glucose was just sitting in my blood and not getting to the cells.

I find, as I have always found, that anything with sugar doesn't really work for me. Personally I would cut out the coke and sweets, which I have always found a short acting spike, to be followed by a drop the other end.

Keto is great for long duration endurance rides, below your lactate threshold, where you are using the aerobic system for your energy for most of the ride.

However, if I am planning to train at a higher intensity or race when I will be above my lactate threshold. I do need some carbohydrates to fuel. I will have 20g of carbohydrate at breakfast, generally porridge, mixed with chia seeds and coconut cream.

Routinely, I will carry nuts (generally almonds) in my pocket, an emergency banana and/or Paleo type bar, free from sugar. If I felt I was starting to feel my energy dip, as I did today after 50 miles into a headwind, I start to nibble on small pieces of banana. I may not even finish the banana in 100 miles. I drink only water, if its very hot and I'm doing a long ride, then electrolytes.

I can only speak for what I have found works for me

Caffeinated energy drink keeps me sharp and alert over time. I have to have caffeine to keep me alert over a distance. On an average temp day, about a bottle an hour. Hotter means more; colder means less.

Then I need SOMETHING chocolate. I use a chewy granola bars that I can break into sections, depending on what I need. They can survive the heat, where sometimes chocolate can’t. If it’s really hot, red licorice does the job- something I can section into carbs that I need. It’s all packable.

For me, about 12 carbs an hour, and .3 units of insulin per hour of insulin make all day riding work for me. Riding is one of my favorite things.

When it’s done, fresh food only.