Energy Chews for Running: When to Use Them and How Many
Most runners come to chews the same way: a gel goes down badly at mile 18, the stomach turns, and the last few miles become a survival exercise rather than a race. Chews solve a real problem. They are easier to meter out, they do not demand a full mouthful of thick syrup in one go, and they let you drip-feed carbohydrate across a run rather than dumping 25g into your gut at once. That last point matters more than most people realise, because gastrointestinal distress is one of the most common reasons runners miss their target time — surveys of endurance events regularly put the rate of significant GI symptoms somewhere between 30% and 50% of finishers.
But chews only work if you use them properly, and "properly" means knowing three things: how much carbohydrate you actually need per hour, how many pastilles that translates to, and when to take them. Get those right and you can run a marathon without ever feeling like you are force-feeding yourself. Get them wrong and you will either underfuel and fade, or overload your gut and pay for it. This guide covers the numbers, the timing, and how to rehearse it all in training.
What Actually Happens When You Take a Chew Mid-Run
Your body stores roughly 400–500g of carbohydrate as glycogen — about 1,600–2,000 kcal — and a decent chunk of that sits in muscle that is not being used by running. At marathon pace, most club runners burn somewhere in the region of 60–70g of carbohydrate per hour. That gives you around two to two and a half hours before the tank runs low, which is exactly why the wall tends to arrive between 30km and 35km rather than at the finish line.
Ingested carbohydrate does two things. It spares your remaining glycogen, and it keeps blood glucose stable so your brain does not start pulling the handbrake. The rate-limiting step is absorption. Glucose crosses the intestinal wall via the SGLT1 transporter, which saturates at around 60g per hour. Fructose uses a completely separate route, GLUT5. Combine the two and you can push total absorption to roughly 90g per hour, which is why the glucose-to-fructose ratio on a label matters as much as the total carbohydrate number.
Chews sit in a useful middle ground. They are more concentrated than a sports drink and less concentrated than a gel, and because you can take one at a time you can spread the load. Chewing also means saliva starts breaking down the carbohydrate before it hits the stomach, which some runners find sits better than a bolus of gel.
How Many Energy Chews for Running Do You Actually Need?
Start with carbohydrate per hour, then work backwards. As a rough framework:
- Under 60 minutes: nothing required. Your glycogen covers it. A parkrun does not need fuelling.
- 60–90 minutes: 30g of carbohydrate per hour is plenty. Useful for a hard tempo or a long midweek run.
- 90 minutes to 2.5 hours: 60g per hour. This is the marathon zone for most people.
- Over 2.5 hours: 60–90g per hour, but only if you have trained your gut for it. Do not attempt 90g on race day having never practised.
Now convert. Most energy pastilles carry between 4g and 6g of carbohydrate each. If yours are 5g, then 60g per hour is twelve pastilles — which sounds like a lot until you space it out as three pastilles every fifteen minutes. That is the practical rhythm most runners settle into: a small handful on a regular beat rather than a big dose on the hour.
The mistake I see repeatedly is runners treating energy chews for running as an occasional pick-me-up rather than a schedule. If you only reach for them when you start feeling flat, you are already fifteen to twenty minutes behind, because carbohydrate takes time to be absorbed and delivered. Fuel to a clock, not to a feeling.
Timing by Distance: A Practical Schedule
Half marathon (90 minutes to 2 hours). Take three or four pastilles about ten minutes before the gun, then a small dose every 20 minutes from the 30-minute mark. You are aiming for roughly 30–45g of carbohydrate total. Anything more is usually unnecessary at this duration.
Marathon (3 to 4.5 hours). Begin fuelling at 30–40 minutes, not later. Take roughly 15g every 15 minutes — around three pastilles — and keep going right through to about 5km from the finish. A 3:45 marathoner following that pattern takes in about 220g of carbohydrate across the race. Always take them with a few mouthfuls of water; concentrated carbohydrate without fluid draws water into the gut and is a reliable route to cramping.
Ultra distance (4 hours plus). Chews become part of a rotation rather than the whole plan. Palate fatigue is real, and after five hours of the same sweet flavour most people simply stop wanting to eat. Alternate chews with savoury real food at aid stations and keep the chews for the sections where you need clean, fast carbohydrate without chewing effort.
Train the Gut Before You Trust It
Carbohydrate absorption is trainable. Studies on repeated high-carbohydrate feeding during exercise show meaningful upregulation of intestinal transporters over roughly two to four weeks, with measurable reductions in both malabsorption and GI symptoms. In practice that means using your race-day fuelling on at least three or four long runs before the event, at the same intervals and the same doses.
Two other habits worth building. First, practise the mechanics — opening a pack, getting pastilles out with cold or gloved hands, chewing while running at pace without gasping. Second, rehearse in the conditions you expect. Sweet flavours that go down easily on a cool morning can become cloying in warm weather, which is a good argument for carrying more than one flavour on a long day out.
What We Use at FTP Endurance Fuel
Our pastilles are built for exactly this kind of drip-feed fuelling. They come in 1kg resealable bulk packs, which means you decant what you need into a small pouch or a gel flask rather than carrying half a dozen individual wrappers you then have to stuff back into a pocket. It is cheaper per gram of carbohydrate than buying single-serve sachets, and it produces considerably less waste on the trail.
The Mixed Fruit Pastilles are the everyday option for running — the flavour rotation genuinely helps on longer efforts, when the same taste hour after hour starts to grate. The Tart Cherry Pastilles are the ones most of our runners reach for around hard sessions and races; Montmorency tart cherry is rich in anthocyanins, the polyphenols linked in the research to reduced oxidative stress and lower perceived muscle soreness in the days following heavy eccentric loading. If you have not tried them before, the taster pack is the sensible way in — test them on a long run before you commit to a kilo.
Fuelling well is not complicated, but it is deliberate. Pick your carbohydrate target, convert it into a number of pastilles, set an interval, and then rehearse it until it is automatic. Do that and energy chews for running stop being an emergency measure and become the reason your last 10km looks like your first. Grab a taster pack, take it out on your next long run, and find out what your gut is genuinely happy with — well before race day makes the decision for you.
