Intra-Workout Carbs UK: Cyclic Dextrin vs Maltodextrin vs Vitargo

Let us deal with the awkward part first: if you train for an hour in a gym, you almost certainly do not need carbohydrate during the session. Muscle glycogen comfortably covers that, and a drink you sip between sets is doing very little other than adding calories.

Where intra-workout carbs genuinely earn their place is longer, harder and more continuous work — long rides and runs, two-a-days, football and rugby sessions, endurance events, high-volume training blocks, and anyone training fasted or in a large calorie deficit. If that is you, then the choice between the powders on this shelf is worth understanding, because they are not interchangeable.

The claim that governs the whole category

This is unusually well defined in Great Britain, and knowing it saves you money.

A carbohydrate-electrolyte solution may state that it contributes to the maintenance of endurance performance during prolonged endurance exercise, and that it enhances the absorption of water during physical exercise. But those claims come with genuinely strict conditions on the finished drink: a defined energy range from carbohydrate, at least 75% of that energy from carbohydrates with a high glycaemic response, a sodium content within a specified band, and an osmolality within a specified range.

The practical consequence is blunt. A tub of plain carbohydrate powder is not a carbohydrate-electrolyte solution. No sodium means no qualifying drink, whatever the front of the pack implies. If you want the properties that claim describes, you either buy a formulated product such as Vitargo Carbohydrates Plus Electrolyte or Trec Vitargo Electro-Energy, or you add electrolytes to a plain carb powder yourself.

There is a second authorised claim worth knowing for afterwards: glycaemic carbohydrates contribute to the recovery of normal muscle function after highly intensive or long-lasting exercise that leads to muscle fatigue and glycogen depletion. That one is conditioned on a substantial intake relative to body weight, taken within a few hours of finishing. It is the regulatory basis for the whole post-workout carb idea.

Osmolality: the thing that actually separates these powders

Every carbohydrate on this shelf ends up as glucose. What differs is how many separate particles are floating in your drink at a given number of grams — and that is what determines how concentrated the drink feels to your stomach.

Break a carbohydrate into lots of small molecules and you get a high particle count, which makes a strong drink. Keep it as a few very large molecules and you get a low particle count, which lets you dissolve more grams into the same volume of water without the drink becoming heavy. That is the entire technical argument in this category, and it explains the price ladder.

Dextrose and glucose

Single sugar molecules. Cheapest, sweetest, and the highest particle count for a given weight — so a strong dextrose drink is the most likely to sit heavily. Fine in small amounts, awkward in large ones.

Maltodextrin

Chains of glucose units — fewer particles than the equivalent weight of dextrose, so a slightly gentler drink, and barely sweet. It is the workhorse of the category and by far the best value per gram of carbohydrate. SciTec Maltodextrin is the plain, unflavoured version. If you are adding carbs to a shake or making up a large bottle for a long session, this is usually the sensible default — add your own electrolytes.

Highly branched cyclic dextrin

Made by enzymatically restructuring starch into large, uniform, highly branched molecules. Because the molecular weight is high, a given number of grams contributes relatively few particles — so you can make a more concentrated drink that still feels light. That is a physical property of the ingredient rather than a health claim, and it is the honest reason people who have struggled with maltodextrin get on better with it. SciTec Cyclic Dextrin is the standard unflavoured option.

Manufacturers also make claims about faster gastric emptying. Treat those as the manufacturer's rationale rather than as established fact — they are not authorised claims and they are not what you are buying. What you are reliably buying is a low-osmolality carbohydrate at a higher price per gram.

Vitargo

A branded high-molecular-weight carbohydrate from barley starch, working on the same principle as cyclic dextrin: very large molecules, low particle count, so a concentrated drink that stays comfortable. It is sold both plain and formulated — SciTec Vitargo, Vitargo Carboloader and the electrolyte versions above. Note the barley origin if you avoid gluten.

Blends and formulated intra-workout products

Most "intra-workout" tubs are a carbohydrate blend plus electrolytes and often aminos: Ghost Intra, Trained By JP Sustain, Trained By JP Performance Fuel, Olimp Carbonox, Allnutrition Carbo Multi Max, BioTechUSA Carbox, OstroVit Carbo and Trec Endurance Carbo Sport. Convenient, flavoured, ready to go. You pay for the formulation, so check the grams of carbohydrate per serving rather than the scoop size.

How much, and how strong

Two numbers do most of the work.

Grams per hour. Common practice for prolonged endurance work is somewhere around 30–60 g of carbohydrate an hour, with higher intakes generally needing a mix of carbohydrate types rather than a single source. Start at the bottom of that and build up — tolerance is trainable, and the classic mistake is going straight to a large intake on race day.

Concentration. A drink in the region of 6–8% carbohydrate — roughly 60–80 g per litre — is the conventional sports-drink strength, and it is roughly where the authorised carbohydrate-electrolyte conditions land too. Much stronger than that and you are relying on the low-osmolality carbohydrates to keep it comfortable.

If you would rather not mix anything, gels do the same job in a sachet — SIS Go Isotonic, HIGH5 Energy Gel and Applied Nutrition Endurance Velocity are the usual options. Our gels vs isotonic drinks guide covers when a gel needs water alongside it, which catches a lot of people out.

Comparing them on one scale

Convert everything to cost per 100 g of carbohydrate: take grams of carbohydrate per serving from the nutrition panel, multiply by servings per pack, divide the price by that, multiply by 100. Plain maltodextrin will win by a distance; cyclic dextrin and Vitargo will not. That is fine — just make sure you are choosing the premium knowingly, because it buys comfort at high concentrations, not more energy.

The short version

• Under about an hour in the gym: you do not need this. Spend the money on protein.
• Long or repeated sessions, on a budget: maltodextrin plus your own electrolytes.
• Long sessions where drinks have upset your stomach before: cyclic dextrin or Vitargo, and build tolerance gradually.
• You want the authorised carbohydrate-electrolyte properties: buy a formulated electrolyte version, or add sodium yourself.

Have a look

All of these sit in our Carbohydrates range, with the electrolyte side in Hydration & Electrolytes. For the wider picture, carbohydrate supplements explained is the plain-English introduction, and supplements for endurance athletes covers how this fits with everything else.

A quick note

This article is general information, not medical or nutritional advice. Food supplements are not a substitute for a varied, balanced diet and a healthy lifestyle, and should not be used to prevent or treat any illness. Always read the product label, do your own research, and speak to a qualified doctor, pharmacist or registered nutritionist before starting a new supplement — especially if you are pregnant, breastfeeding, under 18, taking medication or managing a health condition.