Eating and longer distances - How do you get on?

How much water are you drinking?

Little and often but making sure, as oldnpastit asks, make sure you're hydrating well.

I eat something every hour having had a porridge breakfast first.

I'll have sandwiches typically wrap based as they are squashable twice in the day.

Snacks each hour will be a combination of nakd bars, porridge bars and aldi nut mix and aldi dried mango. I have just added Biltong from a local shop that makes their own.

Drink, just water but plenty. I always have 2 bottles and a sawyer filter.

What are you eating?

I tend to go with 'normal' food and snacks, just regular nibbles, and usually a proper lunch stop(s). I found anything gel/posh bike stuff to disagree with my guts.

Experimenting is the best way.

You have plenty of fat on board so you only really need to replace carbs mid exercise.

Table sugar has the right 1-0.8 ratio of glucose and fructose so is as good as anything. Add cordial to knock the edge off of the sweetness.
For 2-5 hours I can tolerate 100g of sugar per hour (per 750ml bottle) but on longer rides I struggle to drink that much fluid so need to cut back to 40-60g per hour of carbs too as I tried 100g in 500ml water once and it’s too strong for me.

You’ll get all kinds of whacky suggestions which shows that ultimately eating something is more important than what it is. See above 🤣🤣

Everyone's different. Some people can eat pretty much anything, others struggle with solid fuel at all, a mate of mine who was a national level endurance rider - won 24-hour solos etc - used to fuel pretty much solely with gels, which sounded pretty horrid, but was all he could reliably keep down.

I've found avoiding anything that's high in fat is a good move - it digests slowly and screws up your processing of other stuff, I think - ditto smashing a big meal and then riding again, your body will go into hibernating bear mode, or at least mine will. But everyone reacts differently again, I once rode from Dalby to Robin Hood's Bay and back again for fish and chips and ice cream.

Everyone reacted differently to the chips. One, who'd been struggling, was improbably energised. I had a temporary slump. One of the other guys, who'd been going fine, slumped horribly and never recovered. So you can experiment.

But generally, low fat, little and often, stay hydrated is my take. Stuff like flapjack often has quite a high fat content btw. Some commercial bars are good, but a lot of them are stuffed with preservatives and other stuff you've never heard of, if you're going to use them, find one you like. I get on with Clif Bars, which can be a bit sweet, but work for me generally.

Or make your own stuff - rice cakes is the pro solution, not the dry crispy things, stuff that's made from cooked sticky rice, chilled and pressed together - the Feedzone Portables book is a good option for recipes.

What are you eating at the moment? How hard are you riding?

Advice from people who don't have problems is unlikely to be that useful. I can go running on a (normally) full stomach (never tried straight after a curry blowout!), can eat easily on the run, let alone cycling. Did struggle a little bit last year doing a very hilly 100 mile ride round the dales in the heatwave but I'm sure that was more to do with heating than eating. Even then, I'd had enough to eat, just didn't feel very well towards the end.

Have mentioned before, my wife got the GCN cook book and we find their big ride energy drink (home-made gel alternative) is very palatable especially when watered down a bit. But you have to buy a few bags of assorted powdered stuff to mix up.

I’ve ridden 24hrs + on carb drinks, gels and jelly babies supplemented by the occasional pork pie. However, you don’t want to find out on the day of an event/big ride that your stomach doesn’t agree with your dietary choices. I also found that lots of endurance rides turns you into a lean-burn machine - I didn’t need to ingest the volume of carbs most of the online calculators tell you too, otherwise I’d just feel bloated.
Stopping mid-ride for a fry-up means your body diverts blood flow to your stomach to injest food which means there’s less to carry oxygen and fuel  to your muscles. Used to do a midsummer ride down, around and back to the Isle of Wight with a fish supper on the ferry back from Ryde - getting up Portsdown was purgatory.

Yesterday I managed my fastest ever 50 mile club ride with just a toasted teacake and a large cappuccino at the cafe stop, but thats probably not gonna help you.

Depends what you are used to and why you are riding. I don’t race, and i can ride at a good pace for a couple of hours on a cup of coffee and a bowl of cereal, with a bottle or two of juice.

Longer rides i prefer real food, so generic cereal bars to nibble on every 15-30 minutes, little and often. I carry a Torq gel as an emergency bonk ration, trial and error has taught me it's the brand i digest easier. I don’t use any other "energy" product while riding except a hydration tab.

If you are wanting to barf going up a hill, that suggests to me that your body can't power effort as well as digestion, so either reduce the effort, or eat little and often to ease the digestion.

I am in no way qualified on this, just my experience

As crosshair says you get bizarre suggestions from all, like table sugar 😁

Before you respond I know nakd bars have processed sugar but they taste great and are easy to eat so win for me.

Thanks everyone, some really useful advice.

How much water are you drinking?

Lots (for me), I struggle with this as well, I drank about 2.5 litres yesterday, and as per normal two things happened. 1. I just seem to have to wee it all out again, 2. I can feel it all sloshing around inside me which adds to the bloated feeling.

Food I ate yesterday for a 80km 1100m - XC/gravelly type thing was; moving time was 5 hours, I was going pretty steady

Half a commercial flapjack from a garage at about 20kms in (too much fat?)

a packet of bloks (over the course of the day)

A brownie at a cafe stop at about 40km (again, too much fat?)

A flat white at the same

A can of coke at about 60km.

I'm not exactly a fan of the stuff but carbohydrate drinks do actually work on me.

A 1kg tub of high5 powder lives in the garage fridge so I can basically just turn water into Carbs before leaving. Supplement that with a gel or two, maybe a flapjack and that can see me through maybe 6 hours before I really yearn for solid food...

This is fun, if a little unscientific:

.

Oh, and breakfast was scrambled eggs - 3 eggs

Lots (for me), I struggle with this as well, I drank about 2.5 litres yesterday, and as per normal two things happened. 1. I just seem to have to wee it all out again

Yeah, that happens to me. I do find it worth using rehydration tablets.

I did the Exmoor MTB marathon a week or so back, wasn't really sure how long it would take me tbh 4.20 in the end, porridge breakfast plus a couple of croissants as it was a late 10.30 start. On the ride I ate a banana, dropped the other one 😟, half a malt loaf, 3 gels and had a small soft bottle with about 4 scoops of maltodextrin, a pinch of salt and dash of squash. Prefer to drink plain water than have energy in with it, "ate" something every 20mins.

Savoury lots and lots of savoury. The longer my rides are the more I crave strong savoury flavours. Finally did a proper peak ton last month and the food from the Hope Curry House went down a treat. ( which was lucky as there was sod all else open,)

TBH the only two problems I have eating on rides is:
After about 10 hours or so onwards if I've been pushing it.
Being able to carry the damn stuff. Did a few 100km mtb rides in lockdown and my rucksack weighed a bloody ton.

I need to eat normallish food. Not too much obvious sugar. Haven't eated a gel ever, and not used any "sports drink" for 14 years or so. Sandwiches with lashings of tobasco salt and pepper.
Boxes of tomatoes covered in salt and pepper.
Dry spicy salami.
Pizza
Soup
Scones with lashings of clotted cream

( PS, as you can guess, this is for 'plod' rides rather than TTs. Decent pace, but not so fast that i can only digest short chain glucose)

Vive la dufference

I like an eggy breakfast an hour + before a long day - 2 eggs max.

Thereafter a couple of wine gums and a cereal bar every 1r - 1.5hrs. That gets boring after a while so something like wraps spread with peanut butter, bit of grated carrot and mango chutney - rolled up and cut in two, half every hour. Once I get going on that regime I feel good. I have to stop myself eating too much when its available, couple of notable disasters involving overeating at cafe stops and really suffering shortly afterwards.

On a recent multi day trip in warm weather I was getting through 3 litres of water over 8 hrs, that felt fine, but I have to force myself to drink sometimes.

I have found sticking to a regime is better than grazing as and when you feel like it or there's a cafe/shop is better.

Oh and I struggle to avoid a coffee stop - now I try to restrict that to one on a long ride, I think too much caffeine affects my digestion?

I tend to eat very little on rides, I quite often don't feel like much at all. Cafe stop, I'll always have something - granola bar / teacake etc but rarely more than that. I can reliably do 100km road rides on that and a couple of bottles of water. 100km off road would be a different matter, I'd have to resort to bars for that. I like the Torq flapjack ones although Nakd bars and the KIND nut bars (supermarkets, petrol stations) work well for me too. Anything else just sits there and feels horrible. Apple or banana is good for something fresh and to remove the sticky sweet feeling from your mouth.

I did RideLondon a couple of times on gels alone - to get below the magic 4hr mark you basically have to treat the thing as a road race, sit in the groups and no stopping so 4 gels, 2 bottles.

I think with me I was so used to eating during races that it's just stuck with me, I can get by on not a lot. Now I'll always have a cafe stop on a ride but it's never sitting there eating a full English!

If you really struggle with getting food in, the best way to take on energy is to use a proper energy drink.

I'm pretty adapted to 24 hour garage food now, sausage roll or pork pie, cheesy sandwich and a blue Powerade with a bag of jelly baby chasers.

All awful, processed stuff but needs must at 10pm when you're planning on riding through the night...

I tend to stick to normal food these days. If you try enough stuff, eventually you'll find something that works for you.

Half a commercial flapjack from a garage at about 20kms in (too much fat?)

a packet of bloks (over the course of the day)

A brownie at a cafe stop at about 40km (again, too much fat?)

A flat white at the same

A can of coke at about 60km

That doesn't sound anywhere near enough, e.g. I would take a packet of bloks AND maybe a couple of other snacks in the course of an hour if I was on a big ride (and not usually within the first hour when I'm still running on muesli/bananas from breakfast).

I've been trying to move away from the sugary energy products for longer rides, or saving them for hard efforts near the end or something. Naked Bars and the Co-ops little protein energy balls are great for this, they all consist of mostly pureed date which seems like the perfect longer chain carbs to sustain you.

I'll combine these with Bananas (which are still unbeatable in my eye, tasty, portable, reasonably healthy) and mini-soreen just for variety.

The challenge is timing, I don't really want anything big or slow to digest before any big climbs or efforts, so I'll try to time snacks for the top of the previous climb or a wee bit out from the base of the next climb. Probably harder on an MTB so I'd just constantly nibble, that's where the wee 'energy ball' type products are really useful.

Biggest ride of the year a couple of weeks back with lots of pretty nasty punchy climbs, I followed all the above and had half a portion of chips with macaroni cheese on top for lunch, washed down with a big black coffee (I don't like the idea of milky type coffees on long rides? A belly full of milk doesn't appeal).

Any yeah, with the warmer weather I've started using carbohydrate or at the very least electrolyte drinks.

Lots of different advice here based on lots of different types of ride. I wonder what the op's ride was like. Under 6hours or thereabouts at a hard pace my food would be very different from a long day bikepacking for example..

I can (and have) do a steady 100km on the road on water and a banana but I would be pretty bloody hungry when I finished. Up to around 6hours going hard mostly on carb drinks etc, over that and it's much more protein and savoury.

As many say, there's a large dose of trial and error to work it out.

I've done a handful of iron distance triathlons - so for my uncompetitive pace, an hour swim, 6 steady hours biking and then until it gets dark shuffling around a marathon.

For me... porridge/ granola for breakkie, then I've found the combo of clif bars and shot bloks work well on the bike (I find I need something with a bit of 'substance' better for me on the bike - an empty / liquid only stomach doesn't agree with me at all and I start constantly burping and a bit bluuurgh, until there's something more solid down there (maybe the result of being horizontal swimming for an hour ?).

Once on the 'run' I can't take solids without trying to cholesterol to death, so I drop to gels - the Torq rhubarb and custard is best for me.

I find that anything acidic doesn't go well - so citrus drinks are bad choices for me, even the high 5.  I tend to mainly drink water.

As per many others, 'little and often' is the mantra - guzzle half a bottle of fluid in 1 hit and that's a recipe for puking it back up.  (I carry a 0.5 litre soft drinking 'flask'  on the run, so I can sip regularlyy between feed stations and refill it at them).

Having said all of that, I was handed a ham sandwich at a feed station about 16 miles into the mara at the Lakesman a couple of years back, and it was the best food EVER !

How long was the ride? 2 1/2 litres sounds a lot.  It is possible to drink too much

That doesn’t sound anywhere near enough,

Yeah, I was worried someone was going to say that, I was panning to eat more, I had another flapjack with me and I thought I try something savoury at the cafe stop, but I honestly couldn't face it The Coke later on was OK, but the thought of eating the other half of he flapjack...bluuergh.

I've got to get this sorted as I've set myself a 3 day ride at the end of August.

Worth noting as well that a lot of the energy gels/bars etc out there say to consume sometimes as many as 1 every 20-30 minutes which, to most people, is going to be WAY too much, especially if you're not used to them.

I've done ride-leading jobs where some of the punters, especially those new to it or nervous about the event etc are necking gels right from the word go (and this is after an all-inclusive breakfast!) and then wondering why they're sitting in a hedgerow an hour later throwing it all back up again.

Whenever this topic comes up on this forum it seems that most people take pride in eating very little or eating anything that isn't sugar, which is the complete opposite of my experience. Which leads me to believe everyone is different.

I've done loads of 70-100 mile road rides and when I first started doing that sort of distance I really struggled in the last 20-30 mile. I found that start eating almost straight away and eating lots of sugar was the key to feeling fine all the way til home. I've found that savoury foods that you find out and about; like pasties or pork pies etc. do more harm than good. I usually have some carb mix in my bottles, some gels for towards the end of the ride and then a mix of any other carby bars, nature valley, snickers, flap jack etc. cliff bar if I'm feeling fancy for early on.

Gels with the odd bar and sandwich have always worked well with me, but I am weaning myself off the gels now (due to expense and not having any left).

I did a couple of big rides in the Cairngorms last week on:

Ride 1: Triple all-day brekkie sandwich (1.5 rounds) and Tangfastics, plus a caffiene gel.

Ride 2: Tangfastics, with two little pies and a coffee at the lunch stop in Ballater.

Both worked OK, but the first climb and descent after lunch on ride 2 were grim.

You're eating way, way too much. That's a massive amount of sugar and it's why you're struggling. You're also concentrating on the wrong things.

You just need to look at it logically. The body is designed to use its resources and then be replenished. That's why severe dehydration is bad. But hyponatremia kills you. Your body is concentrating on digesting all that food and by the time it's processed it and it's of any use to you. You've finished.

You need to concentrate on salt levels and electrolytes. That's a very personal thing. Especially salt. I could never get my head fully around that and it's a very fine balance. It takes a lot of testing to get right. You need it to absorb the water. But too much and the body won't absorb the water.

Personally I wouldn't eat anything for five hours. Just an electrolyte drink with as little fructose as possible. It's more about what you eat the week before. Especially the day before. Nothing new. Good quality carbs and protein. The day of the big event just a light, easily digestible breakfast.

It's a phycological thing. I'm doing a big event. I must eat to fuel myself. But it's only five hours. It's nothing to the body. As I said before if you eat your body is just wasting energy processing it. High sugar food, the sugar is processed first. Your body uses it and then you get the sugar crash. From what you've said that's why you're having problems.

It's been a long time since I've done anything so my memory is a bit vague. But I've done sixteen hours on an electrolyte drink and a tiny amount of food. Even then the food was more for physiological reasons than fuel. I used to use I think it was called Torq because it's not fructose based. As I've said it was the build up. Then a very light breakfast.

This is obviously just my opinion and what worked for me. But if you look at professional athletes. They have to be doing a long, extreme event before they start consuming food. Little and often. Even with the drink.

This is obviously just my opinion

It's certainly not mine!

But if you look at professional athletes. They have to be doing a long, extreme event before they start consuming food

Depends what you class as extreme or long. Any ride over 3 hours should be fuelled imo unless you are just out for a gentle pootle or you ride involves 20mins riding followed by 10mins chatting at the bottom of a descent or whatever.

 But if you look at professional athletes.

Yeah, I'm not what you think of when you think of professional athletes. 🤣.

You’re eating way, way too much. That’s a massive amount of sugar and it’s why you’re struggling. You’re also concentrating on the wrong things.

You just need to look at it logically. The body is designed to use its resources and then be replenished. That’s why severe dehydration is bad. But hyponatremia kills you. Your body is concentrating on digesting all that food and by the time it’s processed it and it’s of any use to you

Sugar doesn't need to be digested, it just needs to be absorbed that's why it's useful when exercising.

For a 5hr ride, not overly steep ride, that doesn't seem too unreasonable, although I'd probably have more than a brownie at the caff - always difficult to resist a bacon and egg butty IME.

Thats a hell of a lot of water. I doubt I'd have got through a litre. Not surprised you couldn't fit any food in!

Frontier 300 last year, I had to train myself into eating once an hour. First hour would be something small like a mini sorreen bar or a handful of fruit/nut/m&m mix. 2nd hour would be a bit bigger- Torq flapjack or a Clif bar. Plus stops at the foodtations which were ~every 3.5hrs for something more substantial.

The thing for me is to have the food accessible. If I have to stop and take a pack off, I just won't.

"Food in, miles out" was the mantra

If I'm doing a big, hard ride I do find I sometimes struggle to know what I want. During a race, I eat pasta, haribo and one gel an hour. On a longer ride, substitute the pasta for a bagel with peanut butter. Anything else, I find I'm underfuelled or I get gutrot. It took me a decade of racing to find that is what works for me, though.

I have found lately that after a massive ride or race I don't want to eat anything afterwards. My body just goes into shutdown, and when I do eat something I throw it straight back up. I have no idea how to solve that.

But if you look at professional athletes. They have to be doing a long, extreme event before they start consuming food

The Tour coverage has had interviews with some of the "behind the scenes" crew including nutritionists and soigneurs and the riders are eating and drinking constantly.
It's all mapped out for them individually - gone are the days when you'd get any random musette and it'd all have the same stuff in it, this is food and drink tailored to each rider, their diet, their weight, their power output and the tactics of the day.

When Chris Froome did his long-range stage-winning attack in the Giro, they'd planned that down to the last detail and had every available staff member (even back room staff who wouldn't normally be on the race route) stationed at pre-determined points to hand up the required amount of energy.

If I have to stop and take a pack off, I just won’t.

Yeah I find that as well. Especially on my own, stopping to take on board food just seems really hard for some reason that I can't fathom.

You don't say how long a long ride is?

50 road miles / 30 off-road I'd not bother, just stop at a cafe half way. Most reasonably fit people should have enough glycogen stored to get them through 2-3 hours so there's not much needed to top up. There's a whole industry geared up to tell you that you need 4 energy gell's just to do an evening ride but they're wrong and just trying to sell more £2 sachets of jam.

How much are you trying to eat? Ignore what the Garmin says with regards to calories, at an all day pace you'll be burning about 50% of it from stored fat so you only need to be eating about 250 calories from carbs if it says 500 an hour, protein and fat are needed in small quantities, but really they're just unnecessary beyond the minimum you'll get in most foods anyway.

Little and often is the key, so:

50/50 OJ and water in the water bottles, or just OJ if you bonk and get some from a shop or it's winter so you're drinking less. Diluted 50/50 500ml is ~ 250 calories, so that's easy if it's even slightly warm. Chuck an electrolyte tab in too.

Sweets that don't need much chewing, so jelly babies beat fruit pastilles or Haribo. Fruit jelly's beat almost everything.

Bananas

White bread jam sandwiches

Basically anything that doesn't require much chewing. Chewing seems to be what triggers discomfort for me, I think it's the combination of my stomach expecting a bigger meal than there is, and not being able to breathe while eating on the go. Also, only eat at the flat crest of a hill, gives you a few minutes to begin digesting it before the next climb.

If you're stopping, eat! It's free time so make the most of it. If someone's fixing a puncture have a mars bar. If you're at a cafe don't dither with espresso and bottled water, have a full fat latte with a couple of sugars and extra cake, and a can of coke to wash it down.

And the exception that proves the rule - savory stuff like pies. A few hours in once you're fed up with sweets, it's better to eat something than nothing.

Did a 200k Audax a few weeks ago on a ridiculously hot day, much to my surprise I got to the end and rode home still feeling fairly fresh.

Things that don't work for me:
Haribo, a handful of tangfastics from a shared bag is a nice psychological boost, a whole bag as an energy source is way too much gellatin both to chew and digest.

Flapjack, it's fine if it's made up such that the oats really are just a mechanical means to bind the syrup and sugar together. If it's just a half pound chewy biscuit then it's too much like hard work.

Sausage rolls, they're too dry, (vegan) pork pies for the win! Or Homemade sausage roll with loads of pickle under the pastry and cheese on top.

That doesn’t sound anywhere near enough,

Tbh that sounds like plenty to me but heat, pace, terrain etc will make a difference.

Fwiw the longer I ride for the closer I get to just eating 3x a day as normal with a snack in between, so over a 12hr day that's food going in every 2-3hrs. It'd be different for a faster 6hr day ride. 24hr soloists using gels is really specialist stuff and ime longer distance riders don't eat sports foods much.

Basically I find as you ride closer to your natural base pace, the less critical eating is since you're just burning fat and O2, replacing carbs as you go for muscle glycogen to support hill efforts etc since we'll rarely cruise all day.

If you're not able to hold an acceptable (to you) pace without reliance on high energy food (and it's too easy to go overboard and feel ill) then the solution is in endurance training more than eating ime. I used to have a really hard time fuelling long rides, base training and fasted early an miles etc was the fix.

If I have to stop and take a pack off, I just won’t.

Yeah I find that as well. Especially on my own, stopping to take on board food just seems really hard for some reason that I can’t fathom.

I always keep my gels, bars & sweets in my shorts pockets for this reason.

Only the butty goes in my pack.

You don’t say how long a long ride is?

Yeah, it's up thread, but this was 80km off road with just over 1000m of climbing, most of the climbing was short hard efforts.

Haribo, a handful of tangfastics

Yeah, I can't be doing with Tangfastics on a bike-ride, they're too chewy, and sweet. Same with Jelly Babies after about 5-6 of the things, they make me feel sick, no way I'm eating a whole bag of them.

How much are you trying to eat?

Dunno, I don't have an amount in mind, I just need to be able to fuel it enough so I can do a similar distance to that (maybe a bit more climbing) 3 days in a row,

You’re eating way, way too much. That’s a massive amount of sugar and it’s why you’re struggling. You’re also concentrating on the wrong things.

Disagree hugely with the first point (unless you meant way, way too much sugar, which based on recent personal experience I agree).

Total calories might have been 1400-1500kCal assuming a generous 400kCal per cake and 500kCal for the can of coke? 5 hours steady off road (80km and 1100m climbing in 5hrs is a reasonable shift) could easily be 2000kCal burned? Not counting just base metabolism which could add another few hundred?

So unless you're suggesting we should all be running enormous deficits I don't see how that intake could be considered way, way too much.

Edit: missed the last few points, but my maths isn't based on burning fat stores, although I am trying to train this with more longer/easier rides.

500kCal for the can of coke?

140Kcal for regular 330ml can of coke. I was surprised as well. So I use myfitnesspal for calories for this sort of stuff and it thinks I ate;

1/2 Flapjack 266Kcal,

Bloks; 200Kcal,

Brownie (homemade, which is reasonable enough it was a wee cafe) 250Kcal,

Flat white (small) 130Kcal.

846Kcals.

MFP thinks that lot was 140g of carbs, 18g of fat, 6g of protein.

oh, and 2.5lts-ish of water.

Everyone is different, and every ride can be different depending on things like effort level, temperature, tiredness levels etc.

I've found over the years that I struggle with the big breakfast of porridge pre-ride since I end up having a massive crash about an hour in and struggle to catch up again. It also makes me feel heavy and bloated. I tend to eat  a 60g serving of fruit & fiber for breakfast about an hour-90min before heading out. I then eat for moderate intensity (zone 3) rides something like a Eat natural granola bar or Fruislli every hour-90 min, along with about 500ml of torq natural. I like the Torq because it doesn't taste sweet, and it's the sweetness of everything I really struggle with on long rides.

I only resort to gels/shot blocks if the bonk comes since it doesn't land well on the stomach. If I do bonk and it's feasible, I'll stop at a cafe/petrol station for a can of coke and something solid over gels too.  Try and eat as much solid food as you can early in the ride and only switch to the gels later if you're struggling to get stuff down without feeling sick.

Also, when it's hot, it's easy to drink more instead of eating, which ends up with feeling queasy too and makes it hard to stomach the idea of food, especially sweet stuff, which then continues the spiral.

Try something small every hour, but pick where you eat it - eat at the top of hills so you've then got a descent/flat to help the digestion rather than just before hills. If eating something like a sandwich, make sure you give it a good 15min before heading off up high intensity efforts again.

Ultimately it's easy to over science it, but monitoring your effort would be the best way of working it out. It may be that you think you're riding zone 3, but you're doing every hill at threshold which will burn the matches way quicker, and so you're already well in deficit before you consider fueling. If you don't ride with HR, I'd maybe start there.

It's surprising how many are giving fuelling advice that includes what to do if you bonk. It's been years since I have booked.

I've done a fair few longer rides over the last few years (15 - 30+ hours continual) and it's difficult to nail down exactly what works and what doesn't.  What works for me on one ride doesn't always work the next time.  You just sort of make it up as you go.  As a general rule though, I try and replace about half of the calories I burn during the ride but make sure I'm well stocked up on carbs for a few days  before hand.

It's important to take the intensity into account.  It's far harder to digest food at higher intensity than lower intensity.

Assuming the intensity is pretty low I generally try and stick to solid foods, jam butties, pork pies, dates etc for as long as possible to start with but after 7-8 hours I start to struggle with the real stuff.  I then move onto gels (my "secret weapon" is a 500ml soft flask with 375g of Maltodextrin / Fructose mix - basically a 1,500kcal super gel, and sometimes x2 of them!).

I also find that fatty foods & protein rich stuff really can "reset" your stomach if you're going through a bad patch.  I sometimes start craving stuff like apples and salt and vinegar pringles...

Just eat whatever takes your fancy, eating something is better than eating nothing even if it's not the most ideal thing.  You may completely loose your appetite and go through a bad patch, just hang in there and it'll normally come back and then some.

You'll also need to take on lots of water.  If you get dehydrated you'll slow your digestion down even more.

I managed to scoff nearly 8,000kcal on my last epic over 21 hours.

Last thing to add is that your gut does need training to be able to handle such a large quantity of food and there's only 1 way to train it.... big rides and big food!