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Build your own endurance fuel
Drag the glucose-to-fructose ratio, pick your carbohydrate sources, and — if you want to run the experiment — toggle a home hydrogel. The recipe, the cost, the osmolality and the mixing steps update as you go. Train the gut without punishing the bank account.
Your drink
Carbohydrate sources
Maltodextrin is the glucose knob; honey, sugar and fructose are the fructose knob.
Electrolytes
Hydrogel — the “cheap Maurten” experiment
Optional gel-formers that stay liquid in the bottle and set in your stomach. An experiment, not a proven upgrade — rehearse it in training first.
Delivers
2 : 1 G:F
- Carbs
- 89.9 g
- Concentration
- 12%w/v
- Osmolality
- 295isotonic
- Energy
- 353 kcal
DIY race drink
For one 750 mL bottle. Weigh the solids; add water to the mark.
| Maltodextrin | 63 g | 7 tbsp |
| Crystalline fructose | 30 g | 2 tbsp + 1½ tsp |
| Water, to | 750 mL |
Cost to make
CAD 1.18
About 10.7× cheaper than the equivalent in gels (CAD 12.67).
How to mix it
- Weigh the dry ingredients into a 750 mL bottle: 63 g maltodextrin, 30 g crystalline fructose.
- Add about a third of the water and shake until nothing is left on the bottom. Warm water dissolves faster if it is a thick mix.
- Top up to 750 mL and shake again.
- Taste it. If it is too sweet to finish, that is a real problem — dilute it and carry more, or move some carbohydrate to a separate concentrate.
Is the hydrogel worth it? Honestly.
The idea is elegant: sodium alginate and low-methoxyl pectin stay liquid in your near-neutral bottle, then set to a soft gel the moment they hit stomach acid — in theory wrapping the sugar, emptying the stomach faster, and letting you carry very high carbohydrate with less distress. That is the Maurten concept.
Here is the part most sellers skip. When you pool the controlled human trials that compared the gel against the same drink without the gelling agents, the gel adds no reliable benefit — a 2022 meta-analysis was null on performance, carbohydrate oxidation and blood glucose. One running study found the gel about 2.1% faster than a matched drink, but no one has reproduced it, and a nutrient-matched study concluded “the addition of pectin and sodium alginate offers no further benefit.” The gains people credit to the gel almost certainly come from the glucose:fructose ratio and the high, well-tolerated carb rate — the formulation, not the chemistry.
So we offer it as exactly what it is: an optional experiment you run on yourself — probably inert, harmless, and just possibly worth it if you are GI-prone at very high carb rates. The raw materials cost pennies, so it is cheap to test. What is expensive about the commercial product is not the alginate; it is the formulation, the manufacturing consistency, the testing, the packaging and the brand. If the hydrogel helps you, you will find that out in training — not from a label.
Mix cool, and other rules
You cannot “denature” a carbohydrate by making a sports drink — sugars are heat-tolerant. The thing you can wreck is the gel. Heat, and especially heat plus acid, shortens the alginate and pectin chains and leaves you with a weaker gel.
- Mix at 30–40 °C. Cool tap water is ideal. Nothing here needs hot water; boiling water is the one thing to avoid.
- Beat the clumps. The usual home failure is not heat — it is “fish eyes”. Whisk the dry polymers into the dry maltodextrin first, then sprinkle that into the water while stirring, and let it hydrate 15–30 minutes.
- No acid in a hydrogel drink. Lemon, lime and citric acid can set the gel early — in the bottle — and speed the breakdown.
- Make it fresh. Mix the day you use it rather than storing a hydrogel batch for weeks.
A plain sugar-and-salt drink is far more forgiving — these rules matter once you add the polymers.
The ingredient stat sheet
What each carbohydrate does, which transporter carries it, and which knob it turns.
Maltodextrin
The professional base. A glucose polymer, so it carries a lot of glucose with barely any osmotic load — the least sweet, easiest-drinking way to raise glucose.
Dextrose
Pure glucose — the clean control. It reaches the blood a touch faster than maltodextrin, but that is not the bottleneck in endurance (the gut transporter is), and every molecule counts osmotically.
Our take: We strongly suggest maltodextrin over dextrose for any endurance event. Same glucose, but maltodextrin is a polymer: far fewer dissolved particles, so lower osmolality, less water pulled into the gut, better tolerance, and a higher carbohydrate concentration in the bottle. Dextrose barely enters the blood faster — and a high-molecular-weight glucose polymer was oxidised no faster (in one study, slower) than glucose during cycling. Keep dextrose for short, explosive efforts, post-workout glycogen refill, or as a control drink in your own testing — not as your race base.
Table sugar
Sucrose is already a 1:1 glucose-fructose blend and cheap. The middle lever — add it to move toward more fructose without honey flavour.
Maple syrup
Basically a natural liquid table sugar — mostly sucrose, so it splits to a clean ~1:1 glucose-fructose. Predictable and mild-flavoured; lower carb density than table sugar because a third of it is water. The tidy centre lever.
Honey
A natural, fructose-rich glucose-fructose mix with flavour. Already free monosaccharides (not sucrose), so it leans fructose and is osmotically heavier — the fructose knob with taste.
Coconut sugar
Mostly sucrose, so it behaves close to table sugar, plus a little potassium and a flavour. Carries inulin (a FODMAP fibre) — fine in small amounts, a GI risk at a full dose.
Crystalline fructose
Pure fructose on its own transporter — this is what lets total intake climb past ~60 g/h. Alone it is poorly tolerated; it belongs alongside glucose, never on its own.
This calculator gives general information about endurance fueling, not medical or dietetic advice. Fructose, potassium and the soluble-fibre polymers interact with real conditions — if you have a health condition, are pregnant, or take medication, check with a clinician before changing what you drink around exercise. And whatever you build here: rehearse it in training. Nothing new on race day.