Sebastian Sawe's 1:59:30 men's marathon in London last weekend was met first as a barrier event, then as a shoe story, and only by mid-week as a fuelling story. That sequence is increasingly the wrong way round. Sports nutrition partner Maurten confirmed this week that Sawe's race-day carbohydrate intake averaged just over 100 grams per hour, delivered through five hydrogel-based bottles taken at the official feed stations. That figure sits at the upper end of a range that, three years ago, was considered the realistic ceiling of human gastrointestinal tolerance during sustained marathon running.
The frontier has moved quickly. Modelling work published in the Journal of Applied Physiology in 2024 estimated that a male athlete attempting the men's marathon under two hours would require an exogenous carbohydrate bioavailability of around 93 grams per hour, with women requiring a slightly higher 108 grams owing to differing oxidation kinetics. Subsequent practitioner case studies have suggested that this target is achievable but only with twelve to eighteen months of progressive gut training and a dual-source blend — typically glucose and fructose in a roughly 1:0.8 ratio — to push beyond the saturation point of the SGLT1 transporter at around 60 grams per hour.
The recreational picture is markedly different. A 2025 multi-site survey of 2,820 marathon finishers across five major US races, published in the journal Nutrients, found that the average reported carbohydrate intake on race day was 21.7 grams per hour — roughly a third of the conservative 60-gram-per-hour minimum and barely a fifth of the elite 100-gram benchmark. The same survey found a strong, dose-dependent association between higher race-day carbohydrate intake and faster finishing times even after adjusting for training volume and weekly mileage, with the steepest gains observed in runners moving from below 30 grams per hour into the 45 to 70 gram band.
Carbohydrate periodisation in training is the layer that recreational runners most often skip. The Sherman 1981 and Bussau 2002 studies established that well-trained runners can reach maximum glycogen supercompensation simply by eating 8 to 12 grams per kilogram of body weight per day for three days while reducing training volume — no depletion phase required. Modern Maurten-style protocols layer on top of this a six-week pre-race build of long-run feeding sessions targeting 80 to 90 grams per hour to train both gut emptying rate and mitochondrial enzyme density, a process the company's head of science Joel Kainnert has described publicly as "training the inside of the runner."
The shoe arms race has dominated marathon coverage for the last six years, but the next round of marginal gains is likely to come not from foam stack heights or carbon plate geometry but from the marriage of high-rate carbohydrate delivery with the gut-tolerance training required to use it. Maurten now produces a hydrogel mix that delivers 320 milligrams of carbohydrate per millilitre, up from the original 240 in 2018; rivals Precision Fuel & Hydration and SiS have responded with their own concentrated formulations. For the recreational runner the takeaway is simpler: the gap between elite and amateur fuelling now comfortably exceeds the gap between elite and amateur footwear, and closing it is cheap, evidence-based and almost entirely within the runner's own control.