Most endurance athletes are under-fuelling and the simplest fix is often the most overlooked: a chew you can actually keep eating. The modern guidance for longer sessions sits at roughly 60–90 g of carbohydrate per hour for most athletes, rising toward 120 g/h for trained athletes on long, hard days. Yet most people take in far less, and pay for it with the late-session fade everyone knows. Here's how much you really need, why chews are such an easy way to get there, and how to train your gut to take on more over time.
Why carbohydrate is the lever that matters
During hard, prolonged exercise your body leans heavily on carbohydrate. You store some as glycogen, but those stores are finite, enough for roughly 90 minutes of hard work before they run low. Once they do, your blood sugar dips, perceived effort climbs, and your pace falls off a cliff. That's "hitting the wall," and it's almost always a fuelling problem.
Taking carbohydrate on board during exercise tops up your blood glucose and spares your limited glycogen, keeping your power and pace where you want them for longer. The challenge isn't knowing you should fuel, it's actually getting enough in, consistently, for hours. That's where format matters.
The numbers: how much per hour?
For years the standard advice was 30–60 g per hour. Current thinking has moved on:
- Up to ~60 g/h: achievable from a single carbohydrate source (glucose alone).
- Up to ~90 g/h: achievable for most athletes using a mix of carbohydrate types.
- Up to ~120 g/h: the domain of highly trained athletes on very long events, with a well-trained gut.
The reason you can't just keep loading glucose comes down to absorption, and it's the key to understanding where a chew fits.
Why glucose has a ceiling
Glucose is absorbed through a single transporter (SGLT1) with a limited capacity, which is why glucose alone tops out around 60 g/h. Push past that and the excess sits in your gut, drawing in water and causing the bloating and distress that ends races.
Fructose is absorbed via a different transporter (GLUT5). Combining glucose and fructose, a dual-carb approach, uses two routes at once, raising how much carbohydrate you can take in and use per hour. So in practice, your fuelling has two layers: a reliable glucose base, and a fructose top-up when you want to go higher.
Why a chew is the perfect base layer
A glucose-based chew is the easiest, most reliable way to lay down your base carbohydrate and the reasons are practical as much as physiological.
Our CEL50 chew is built for exactly this job: 50 g of carbohydrate per packet, split into five 10 g blocks. That structure is a quiet superpower for fuelling consistently:
- Precise, bite-sized dosing. A 10 g block every 10–12 minutes keeps a steady stream of fuel coming, rather than forcing a big hit all at once. It's far easier on the gut than gulping a large dose.
- Easy to keep eating. Chews give you something to bite on and a change from sweet liquids and the single biggest cause of late-race under-fuelling is flavour fatigue, where athletes quietly stop eating. A palatable chew helps you keep going when it matters most.
- Electrolytes built in. CEL50 also carries added sodium (267 mg] per serving), so you're topping up salt as you fuel, handy on long or hot sessions where most chews leave you to carry tablets separately.
One CEL50 packet delivers close to a full hour of glucose-based fuelling on its own, a simple, countable base you can take almost on autopilot.
Going higher: chew + top-up
Because a chew like CEL50 is glucose-based, it's effective right up to that ~60 g/h ceiling. To climb toward 80–90 g/h, you layer a glucose-and-fructose source, a gel or drink mix, over your chew base. The chew handles your steady glucose intake; the gel adds the fructose that opens the second absorption route.t's also easier to manage on race day: a simple chew base you take on autopilot, plus a top-up you reach for when intensity or duration demands it.
How to train your gut to take more
Your absorption capacity isn't fixed, it can be raised, but only gradually. Trying to jump from 40 g/h to 100 g/h on race day is the fastest route to a blow-up. "Gut training" means progressively exposing your system to more carbohydrate in training so it adapts.
A simple chew-based progression:
- Find your baseline. How much are you actually taking per hour now? The 10 g blocks in a CEL50 packet make this easy to count.
- Add one block at a time. Increase by roughly 10 g/h — one extra block — every one to two weeks, always in training.
- Add fructose as you climb. As you pass ~60 g/h, bring in a gel or drink-mix top-up so the extra carbohydrate has a second route.
- Practise at race intensity, with race-day products. Your gut behaves differently when you're working hard — rehearse it.
Counting in blocks turns a vague target into something concrete: "I'm at four blocks an hour, let's build to five."
How much will a long session really take?
It's worth doing the maths, because it's more than most people pack. A four-hour ride at ~70 g/h needs around 280 g of carbohydrate. As a chew base (say ~50 g/h) that's roughly four to five CEL50 packets across the ride, with a fructose gel layered on to reach the full rate. Long sessions are hungry — plan and carry accordingly.
Common fuelling mistakes to avoid
- Under-fuelling full stop — the biggest one. Most people take in far less than they think.
- Starting too late — begin early, before you feel you need it.
- Letting flavour fatigue stop you — vary your formats; a chew is an easy way to keep eating.
- Relying on glucose alone for high rates — past ~60 g/h you need a fructose source too.
