Two carbs, two routes
Glucose and fructose cross the gut wall through different transporters. The glucose transporter starts to saturate above about 1.2g a minute, roughly 72g an hour. Fructose has its own, so adding it lets more carbohydrate through.
Lúthri uses maltodextrin, a chain of glucose, and fructose in a 2:1 ratio. A 2025 meta-analysis of 14 randomised trials in 125 endurance athletes found the glucose and fructose blend raised the rate at which ingested carbohydrate was burned as fuel by about 0.27g a minute, compared with glucose alone. Earlier work reported rates up to 65% higher.
Sources: Glucose-fructose versus glucose on oxidation rate, systematic review and meta-analysis, 2025 · Fructose for endurance exercise performance and recovery, The Physiological Society · Multiple transportable carbohydrates and their benefits, Gatorade Sports Science Institute