Here's the thing nobody tells you about fuelling a century. You already know the science. Sixty to ninety grams of carbs per hour, start early, don't wait until you're hungry. That information is everywhere now. What nobody walks you through is the operational side — the part where you're standing in your kitchen the night before with a pile of gels, flapjacks, and drink mix powder, trying to work out what fits in three jersey pockets and two bottles, what you'll grab at a feed station you've never seen, and how to eat a sticky rice cake at 30 kilometres an hour without covering yourself in cling film.
The nutritional science of a century is solved. The logistics of actually executing it while riding a bicycle for six hours is where most people come unstuck. So let me break this down — not the grams per hour, but everything around them.
The night before: carb loading without the pasta mountain
Carb loading has a reputation problem. People hear the phrase and picture a mountain of spaghetti bolognese, eating until they feel ill, then lying on the sofa groaning. That is not what the science describes and it is not what works.
What the research actually supports — and Dr James Morton has spoken about this extensively — is a sustained, moderate increase in carbohydrate intake across the full day before the ride. Not one enormous meal. A full day of eating carb-rich.
Here's the target: 8-10 grams of carbohydrate per kilogram of bodyweight across the entire day before your century. For a 75kg rider, that is 600-750g of carbohydrate. That sounds like a lot, and it is, but spread across three meals plus snacks it becomes manageable rather than punishing.
What that actually looks like in practice
Breakfast: Porridge with honey and banana, plus a couple of slices of white toast with jam. Maybe a glass of orange juice. That's roughly 100-120g of carbs right there.
Lunch: A large jacket potato with beans, a bread roll on the side, a piece of fruit. Another 100-120g.
Afternoon snack: Flapjack, a handful of jelly babies, maybe a smoothie. Call it 60-80g.
Dinner: Rice with chicken, a decent portion, bread on the side, followed by rice pudding or a sticky toffee pudding. Another 150-180g.
Evening snack: More toast, a bowl of cereal, maybe a banana. Another 60-80g.
That brings you to roughly 500-580g across the day, and you can push it higher with extra snacks, larger portions, or a glass of fruit juice with meals. The key is that no single meal is painful. You just eat carb-heavy at every sitting and top up between them.
Two things to keep moderate: fibre and fat. Both slow digestion. Keep fibre to normal or slightly below normal levels — this is not the day for a massive salad or a bowl of bran. And keep fat moderate, not zero, but not a greasy takeaway either. You want everything moving through your gut cleanly by the morning.
Breakfast timing: the two-hour minimum
Your pre-ride breakfast needs to be finished at least two hours before you roll out, ideally closer to three. This gives your stomach time to empty and your blood sugar time to stabilise. If you eat too close to the start, you can get a reactive blood sugar drop in the first 30 minutes of riding that mimics bonking and panics first-timers who think they're already in trouble.
For an 8am start, that means eating at 5am or 6am. Not glamorous. Set an alarm, eat, go back to bed for an hour if you can.
The breakfast itself is the same as the night before: carb-rich, low fibre, a little protein. Porridge with honey. White toast with jam. Rice with a poached egg. Aim for 1-2g of carbohydrate per kilogram of bodyweight. For our 75kg rider, that is 75-150g of carbs at breakfast.
And here is where it gets really interesting: have a final small top-up in the last 10-15 minutes before you start. A gel, a banana, a few sweets. This tops up liver glycogen right at the starting gun and eliminates the early-ride dip entirely. Tim Podlogar's research at Ineos Grenadiers has shown this pre-start carb hit is worth doing — and the pros do it religiously.
Jersey pocket management: the system that saves your ride
Let me be really clear about this: jersey pocket organisation is not a minor detail. It is the difference between eating smoothly every 20 minutes and fumbling around behind your back at 35 kilometres an hour, pulling out the wrong thing, dropping wrappers, and eventually giving up on eating because it's too much hassle. I've seen riders bonk not because they didn't carry enough food, but because getting to it was so annoying they stopped trying.
Here is the system that works.
Three pockets, three jobs
Right pocket — the next thing you eat. This is your active fuelling pocket. Pre-ride, load it with whatever you'll eat first, in the order you'll eat it. When you reach back, you grab whatever's on top, eat it, done. No rummaging. No thinking. One motion.
Left pocket — empties and wrappers. Gel wrappers, foil, cling film, empty bar packets. Everything used goes in the left. This keeps your right pocket clean and uncluttered, and it means you're not throwing rubbish on the road.
Centre pocket — spares and your phone. Phone goes here, wrapped in a sandwich bag if it's wet. Also your backup gels and any non-food items: mini pump, tyre levers, a lightweight gilet if the weather's changeable. The centre pocket sits against your back and doesn't bounce, so it's the best place for your phone.
Preparing your food for pocket life
Before race morning, unwrap and repackage everything. Gels: tear the top notch so they're ready to rip open one-handed. Flapjacks: cut into bite-sized pieces and wrap in cling film as a single parcel, easy to eat piece by piece. Rice cakes: same deal, cling film, individual portions. Jam sandwiches: cut into quarters, one layer of cling film.
The aim is that nothing in your pocket requires two hands, teeth plus a hand, or any thought. You reach back, grab, eat. If you have to stop pedalling or look down to manage your food, the packaging has failed.
The pocket reload at feed stations
When you stop at a feed station, the first thing you do is move remaining food from the right pocket to the centre pocket as backup. Then reload the right pocket with fresh supplies. Left pocket gets emptied into a bin. This takes 30 seconds and keeps the system running cleanly for the next section.
What to carry versus what to resupply
This is the question that causes the most pre-ride anxiety, and the answer is simpler than people make it.
Carry enough to cover 90 minutes of unsupported riding. That is your buffer. If something goes wrong — a feed station runs out, you miss one, the gap between stations is longer than expected — you have fuel to keep riding until the next resupply point.
At 75-90g of carbs per hour, 90 minutes means carrying roughly 110-135g of carbohydrate on your person at all times. In practice, that looks like:
- 3-4 energy gels (75-100g of carbs)
- 1 flapjack or a couple of jam sandwich quarters (25-40g)
- A bottle of drink mix (40-60g in one 500ml bottle)
That fits comfortably in your pockets and your bottles. You are not trying to carry enough for the entire ride. You are carrying enough to survive the gaps.
What you don't need to carry
The full six hours' worth of food. I see riders at the start of sportives with jersey pockets bulging, food stuffed down their bib shorts, a top-tube bag full of gels, looking like a mobile Tesco. That is unnecessary weight, it's uncomfortable, and it messes with your bike handling. Carry 90 minutes. Resupply at the stops. Trust the system.
Feed station strategy: what to grab, what to skip
Here's the thing nobody tells you about sportive feed stations. They are not restaurants. They are resupply points. And your job when you arrive is to execute a plan, not to browse.
What's typically on offer
Most well-organised century sportives provide: water, electrolyte drink, bananas, flapjacks or cake, sometimes jelly babies or wine gums, occasionally jam sandwiches, and usually some kind of biscuit. Better-organised events add gels, sometimes brand-specific nutrition products.
What to grab
Water. Always. Top up both bottles. Even if they're half full. This is non-negotiable. Dehydration compounds faster than hunger, and the next feed station might be an hour away.
Bananas. Perfect cycling food. Easy to digest, roughly 25g of carbs, peels off in one motion, and you can eat it while rolling if you need to. Take two — eat one now, pocket one for later.
Electrolyte drink. If they're mixing it, get a bottle. If it's a brand you haven't trained with, fill one bottle and keep the other as plain water. Never go both bottles with an unfamiliar product.
Jelly babies or sweets. Fast sugar, easy to pocket, no wrapper drama. Grab a handful.
What to skip
Anything you haven't eaten on a training ride before. This is not the day to try a new gel brand, a new bar, or the mystery energy drink on the table. Your gut has been trained on specific foods. Respect that training. Race day is not an experiment.
Heavy cake. It looks tempting, it tastes great, it sits in your stomach like a brick at mile 60. Dense, high-fat baked goods slow gastric emptying and compete for blood flow your legs need. If you must, one small piece. Not a slab.
Too much time. Feed stations are seductive. You stop, you eat, someone hands you tea, you chat to the bloke next to you about his derailleur, and suddenly 15 minutes have passed. Your legs have cooled, your rhythm is broken, and you've got to accelerate back to pace. Get in, execute the plan, get out. Two to three minutes maximum unless you need a genuine mechanical or comfort break.
The last 20 miles problem
This is the section that separates people who understand fuelling from people who know the theory but don't apply it.
Almost every century rider has the same experience the first time: the first 80 miles feel fine, then somewhere between mile 80 and 85, the wheels come off. Power drops. Speed drops. Everything feels twice as hard. The natural assumption is that you're tired, that your legs have simply run out of fitness. And sometimes that is part of it.
But here's where it gets really interesting. The collapse at mile 80 is almost never caused by what happens at mile 80. It's caused by what you did — or didn't do — between miles 30 and 60.
The fuelling debt
The bonk is a debt. You accumulate it over hours, and by the time you feel it, you're already 30-45 minutes behind on carbohydrates. Your liver and muscle glycogen are depleted, and no amount of frantic gel-eating at mile 82 will repay the deficit quickly enough. Digestion takes 20-30 minutes to deliver those carbs to your bloodstream. That's 20-30 minutes of riding on empty.
The riders who blow up in the final 20 miles are consistently the ones who under-fuelled between hours 2 and 4. That's the window where you feel strong, the miles are clicking by, you don't feel hungry, and it's easy to skip a gel or forget to eat for 40 minutes. Every skipped feed in that window is a withdrawal from an account you'll need at mile 85.
The fix
It's entirely fixable. Eat on schedule from the very first hour, and never deviate. Set a timer on your head unit or watch — every 20 minutes, eat something. Not when you feel like it. Not when you're hungry. On the clock. The riders who finish a century strong are the ones who ate when they didn't feel they needed to.
For the final 20 miles specifically, shift your fuelling entirely to fast-absorbing sources. Gels, drink mix, jelly babies. Nothing that needs chewing or digesting slowly. And a caffeinated gel at mile 80 is one of the most well-evidenced performance interventions in endurance sport — caffeine takes about 15-20 minutes to hit, which times it perfectly for the final push.
Hot day versus cold day: the adjustments that matter
Temperature changes the fuelling equation, but not in the way most people assume. Let me break this down.
Hot-day fuelling
On a hot day — anything above 25 degrees Celsius — you need more fluid and more sodium, but not more total carbohydrate. Your caloric demands don't increase dramatically in the heat; your cooling demands do. You sweat more, you lose more sodium, and dehydration becomes the primary threat rather than glycogen depletion.
Practical adjustments:
- Increase fluid to 750-1000ml per hour. Fill both bottles at every feed station, no exceptions.
- Add extra sodium. A sodium tab in every bottle, or a pinch of table salt if you're on a budget. Aim for 500-1000mg of sodium per hour in sweat-heavy conditions.
- Shift toward liquid carbs. Drink mix delivers carbohydrate and fluid simultaneously. On a 35-degree day, getting 40-50g of your hourly carbs from drink mix rather than solid food saves you from having to eat and drink separately.
- Freeze one bottle the night before. It'll be half-melted by the time you need it, cold enough to actually cool you, and it gives you something to look forward to on the second half.
Cold-day fuelling
Cold-day fuelling is, counterintuitively, harder to get right. Your caloric needs stay roughly the same — you're still riding the same power for the same duration — but your appetite drops, your thirst drops, and everything tells you that you don't need to eat or drink as much.
You do.
Practical adjustments:
- Eat by schedule, not appetite. This is even more important in the cold because your body's hunger signals are suppressed. The timer on your head unit is your best friend.
- Warm drink mix helps. If you can start with a warm bottle — fill a regular bidon with warm drink mix, it won't melt — the carbs go down easier and the warmth is properly welcome in the first hour.
- Solid food works better in the cold. Your gut handles flapjacks, sandwiches, and rice cakes more easily when you're not heat-stressed. Take advantage of that and rely on real food earlier and longer.
- Don't reduce fluid below 500ml per hour. Even when it's cold and you don't feel thirsty. You're still losing fluid through respiration and moderate sweating, and dehydration in the cold is a silent problem because you never feel it until your power drops.
Budget fuelling versus premium products
Let me be really clear about this. The gut does not read the label.
A gram of carbohydrate from a 20p supermarket flapjack does exactly the same job as a gram of carbohydrate from a three-quid boutique gel. Both arrive in your bloodstream as glucose and fructose. Both top up glycogen. Both keep you riding. The molecule doesn't know what you paid for it.
What premium products actually give you
Two things, and only two things.
Convenience. Gels are small, light, pre-portioned, and easy to eat one-handed while riding. You're paying for packaging engineering, not nutritional superiority. A gel is 22g of carbs in a form factor that fits in a jersey pocket and opens with one hand. That's actually useful.
Consistency. Brand-name products are precisely measured. You know a gel is 22g of carbs, every time. With a homemade jam sandwich, you're estimating. Over six hours of riding, estimates drift. For some people, that precision is worth paying for.
What budget alternatives actually deliver
Everything else. Here's a budget century fuelling kit that delivers the same grams-per-hour as a premium setup:
- Supermarket flapjacks — roughly 30g of carbs each, about 50p. Cut in half, wrap in cling film.
- Jam sandwiches on white bread — about 40g of carbs per sandwich, costs pennies. Quarter them, cling film.
- Jelly babies — roughly 5g of carbs per sweet. A 150g bag from the corner shop costs a pound and gives you 120g of fast-acting carbohydrate.
- Table sugar drink mix — 40g of white sugar plus a pinch of salt in a 500ml bottle. That's 40g of carbs for about 2p. Add a splash of squash for flavour if plain sugar water offends you.
- Bananas — 25g of carbs each, portable, self-packaged by nature.
A full century's worth of budget fuel — enough to hit 75g of carbs per hour for six hours — costs less than a fiver. The same in premium gels and bars costs thirty to forty pounds.
Where the money actually matters
There is one area where spending more makes a measurable difference: electrolyte and sodium products. Getting your sodium right matters for absorption and cramp prevention, and accurately dosed electrolyte tabs or sachets are far easier to manage than eyeballing table salt into bottles. This is the one place where I'd say spend the money.
Everything else — the carbs themselves — buy cheap, eat often.
Bottles versus bladders
For a century, two standard 500-750ml bidons in your frame cages. Not a bladder. Not a hydration pack.
Here's why. Bottles let you see how much you've drunk. They're easy to refill at feed stations — hand one over, get one back, done. They let you run different liquids in each cage — plain water in one, carb drink in the other. And they're accessible without reaching over your shoulder.
Hydration bladders have their place — multi-day ultras, mountain biking, off-road events where bottle cages bounce empty. For a road century with feed stations every 20-30 miles, bottles are simpler, faster, and more practical.
One upgrade worth making: if your frame fits it, carry a third bottle in a behind-the-saddle cage or a downtube sling on hot days. That extra 500ml of water can cover the gap between feed stations when you're sweating heavily.
The pre-ride checklist
The night before your century, lay everything out. Not in the morning when you're half-asleep and anxious. The night before, calmly, with a cup of tea.
Food for the bike:
- Right pocket load: first 90 minutes of fuel, pre-opened and wrapped
- Centre pocket backup: 2-3 extra gels for emergencies
- Drink mix powder pre-measured into sandwich bags or small containers
Bottles:
- One filled with drink mix, one with plain water
- Spare powder for refills at feed stations
Jersey pocket layout:
- Right: active fuel
- Left: empty (wrapper pocket)
- Centre: phone in a bag, spare gels, any non-food essentials
Morning-of timeline:
- Alarm, breakfast, back to bed if possible
- Final top-up gel or banana 10-15 minutes before start
- Bottles on bike, pockets loaded, brain switched off
That last point is serious. Once you've done the prep, stop thinking about it. The plan is set. You just execute it. Every 20 minutes, eat. Every feed station, refill. Right pocket, grab, eat, left pocket. Done.
The real skill is execution
The nutrition science of a century ride fits on an index card. The logistics of actually doing it — carrying the right food, in the right pockets, resupplying at the right moments, adjusting for heat or cold, staying disciplined through the middle hours when you feel invincible — that takes practice and a system.
Build the system on your long training rides. Try the pocket layout. Test your feed station routine. Practise eating one-handed. Find out which foods survive three hours in a warm jersey pocket and which turn into a disaster. By the time you stand on the start line, fuelling should be boring. Automatic. The least interesting part of your day.
Because here's the good news: once you've nailed the logistics, you never think about them again. You just ride. And mile 90 feels like mile 30.
If you want structured fuelling plans, training guidance, and a community of riders who've figured this stuff out through trial and a lot of error, that's what the Not Done Yet group is for. Members get direct access to ask the specific questions — the "what do I eat at 5am when I'm nervous" questions — that no blog post can answer for your exact situation. It's $195 a month at skool.com/roadmancycling.
Now go and lay your pockets out.