Carbohydrate strategy: how much can your gut absorb per hour?
Single-sugar drinks cap out around 60g of carbohydrate per hour. Multiple-transportable-carb blends can push that ceiling higher — with less GI distress.
Endurance carbohydrate intake is limited by gut absorption, not just how much you can physically drink. Maltodextrin — a glucose polymer — is broken down and absorbed as glucose via the SGLT1 transporter, which saturates at roughly 60g per hour for most athletes. Rely on a single glucose-route source past that and much of it sits unabsorbed, pulling water into the gut and increasing GI distress risk.
Why maltodextrin:fructose blends raise the ceiling
Fructose is absorbed through a separate transporter, GLUT5. Because maltodextrin-derived glucose and fructose use independent gut transporters, combining maltodextrin and fructose in the right ratio lets total carbohydrate absorption exceed the ~60g/hr single-transporter ceiling — commonly cited in the 80–90g/hr range for well-trained athletes using multiple-transportable-carb strategies. TODO: cite primary sports-science literature for these figures.
Where sodium fits in
Sodium doesn't directly affect the SGLT1/GLUT5 ceiling, but it does affect fluid absorption and how comfortable a given carbohydrate concentration feels in the gut during exercise — which is why Solute engineers the sodium, maltodextrin, and fructose ratio together rather than treating carbohydrate strategy in isolation.
The practical upshot: your personal carbohydrate ceiling depends on training your gut over time and getting the maltodextrin:fructose ratio right for your session length and intensity — both of which your Solute formula accounts for.
This is a seed draft written to demonstrate the article template. TODO: fact-check every quantitative claim, add citations, assign a real author, and remove the draft flag before publishing.