In Post 00, we established why maltodextrin became the default carbohydrate carrier in sport nutrition: it delivers a high glucose load in a compact, gut-tolerable format. For events under 60 minutes at moderate intensity, that profile is largely adequate.

But there is a ceiling. And it is built into the biology of how your intestine absorbs glucose.

Understanding that ceiling — and why honey's natural glucose-fructose composition may help work around that single-transporter limitation — is what this post is about.

The Single-Transporter Absorption Limit

Glucose, and glucose-derived carbohydrates like maltodextrin, are absorbed in the small intestine primarily through a sodium-glucose co-transporter known as SGLT1. This transporter has a finite capacity: research suggests it becomes saturated at approximately 60 grams of glucose per hour, regardless of how much carbohydrate you consume above that threshold.^[1]

For events lasting under 75–90 minutes, this ceiling rarely matters. Most athletes are not consuming carbohydrates at a rate that challenges SGLT1 saturation in shorter efforts. But in events extending beyond 90 minutes — a long ride, triathlon, ultra-distance session, or longer race effort — the mathematics shift. Maintaining performance requires progressively higher carbohydrate delivery, and a single-transporter system becomes a genuine limiting factor.

The practical consequence: consuming additional maltodextrin-dominant gels above the SGLT1 saturation point does not increase the amount of carbohydrate reaching working muscle. It increases the amount sitting unabsorbed in the gut — and the probability of the gastrointestinal distress that endurance athletes know well.

The Dual-Transporter Solution

Fructose uses a completely separate intestinal transporter: GLUT5. Because GLUT5 operates independently of SGLT1, combining fructose with glucose allows the gut to absorb from two parallel channels simultaneously rather than queuing everything through one.

The performance implications of this parallel absorption architecture have been extensively studied. Research by Currell and Jeukendrup demonstrated that cyclists ingesting a glucose-fructose combination improved average power output by a further 8% over and above the improvement achieved with glucose alone, compared to placebo — a finding subsequently replicated across 100km time trial and mountain bike race formats.^[2]

The mechanism is quantifiable: where single-transporter glucose sources are absorbed at approximately 1 gram per minute, research suggests that a combined glucose-fructose source may increase total carbohydrate absorption to approximately 1.75 grams per minute — supporting carbohydrate intake targets of up to 90 grams per hour in longer efforts.^[3]

This dual-transporter principle is now reflected in mainstream sports nutrition recommendations. Nutritional guidelines for events exceeding 2.5 hours have been updated to 90g carbohydrate per hour, contingent on consuming mixed-transporter carbohydrate sources rather than single-source glucose formulations.^[4]

Where Honey Fits This Picture

Honey is a naturally occurring blend of fructose and glucose — approximately 35–40% fructose and 30–35% glucose by composition, with small quantities of other disaccharides making up the remainder.^[5] This means honey arrives with the dual-transporter carbohydrate architecture that sports science research has identified as optimal for sustained exercise — not through formulation engineering, but through its natural botanical origin.

A systematic review published in Nutrients (2019) examined nine studies on honey supplementation combined with exercise and noted that honey's fructose-glucose composition creates a theoretical basis for positive effects when consumed before, during, or after endurance exercise — consistent with dual-transporter absorption research.^[6]

Research cited in ScienceDirect further observed that honey's glycaemic index varies between approximately 32 and 87 depending on botanical source and fructose-to-glucose ratio — with higher fructose content associated with lower GI values.^[7] This variability is relevant to how different honey varietals behave as sport fuel: a fir honey (honeydew, lower fructose-to-glucose ceiling) and an acacia-type floral honey will produce different absorption and blood glucose kinetics.

It is important to be precise here. Research on honey as a sport fuel consistently describes performance outcomes as comparable to manufactured carbohydrate supplements — not categorically superior in controlled settings.^[6] What honey offers is not a radical departure from the carbohydrate absorption science. What it offers is a whole-food source that arrives already configured with the dual-transporter carbohydrate ratio that processed formulations must engineer in.

The additional compounds present in honey — polyphenols, flavonoids, trace minerals, enzymes — are a separate question. Post 09 of this series addresses what research suggests about those compounds in a recovery context. For the purpose of this post, the case rests on the carbohydrate architecture alone.

GI Tolerance in Singapore's Tropical Training Environment

Gastrointestinal tolerance in hot, humid conditions is a practical concern that does not always surface in temperate-climate laboratory studies.

Singapore's training and racing environment is characterised by high humidity throughout the year — mean annual relative humidity of approximately 82%, with common afternoon temperatures above 32°C during inter-monsoon periods — placing elevated demands on gut blood flow relative to working muscle.^[8]

Research has documented that gastrointestinal complaints during exercise are prevalent across endurance sport, with heat stress identified as a compounding factor.^[8] Under these conditions, the osmolality and absorption characteristics of fuel become more consequential: high-concentration maltodextrin solutions that are well-tolerated in controlled lab conditions may produce different gut responses in field conditions.

Honey-based gels are still concentrated carbohydrate fuel, so individual gut tolerance must be tested during training. Whether an individual athlete tolerates honey-based gels better or worse than maltodextrin-dominant alternatives is a personal variable that should be established across multiple training sessions before race day.

RealFUEL+ recommends testing any new fuel format under race-representative conditions before committing to it in competition.

What This Means for Nomad Honey Gels

Nomad honey gels are formulated on an organic Greek honey base — no maltodextrin, no glucose syrup, no synthetic carbohydrate carrier. The carbohydrate profile comes entirely from the naturally occurring fructose and glucose in the honey, supplemented by functional additions depending on variant: guarana and beetroot in the Beetroot Gel, bee pollen in the Pollen Gel, cocoa and added caffeine in the Cocoa Gel, peanut in the Peanut Gel.

Each gel is built on a honey base that naturally contains both glucose and fructose. The individual variants add functional layers — nitrate loading, pollen amino acids, caffeine timing, sustained-protein delivery — that subsequent posts in this series address in detail.

For athletes new to the range, the Nomad Starter Kit includes one gel in each of the four flavours — designed specifically for in-training evaluation across multiple sessions before race day selection.