HYPE: Ingesting carbohydrate during prolonged endurance exercise can improve performance compared with no carbohydrate.
But what does the evidence actually show?
Carbohydrate during prolonged endurance exercise can improve performance compared with no carbohydrate. The benefit depends on the event and fuelling context; it does not mean every short workout needs gels or sports drinks.
The claim
Ingesting carbohydrate during prolonged endurance exercise can improve performance compared with no carbohydrate. The rating below applies to this specific outcome and population, rather than every claim associated with the subject.
Why people believe it
During sustained exercise, carbohydrate can supply usable fuel as demands increase and stored carbohydrate becomes less available. Consuming it during a long event is a different question from whether carbohydrate is essential at every meal or whether a particular sports brand is superior. [1] [3]
What the evidence actually shows
A large trial synthesis supports the basic effect
A 2021 meta-analysis included 96 studies of carbohydrate solutions during prolonged exercise. It found a beneficial average performance effect, with a standardised mean difference of 0.43. That is not a 43% improvement in speed: standardised effects combine different tests on a common statistical scale. [1]
The recent review adds caution about precision
A 2026 umbrella review found the clearest support in efforts lasting roughly one to four hours. It also rated 11 of its 15 included reviews low or critically low quality. Counting hundreds of trials across overlapping reviews would exaggerate the number of independent experiments. The review reinforces context rather than establishing one perfect dose or guaranteed benefit. [2]
Sports-nutrition guidance treats fuel as a tool
The Academy of Nutrition and Dietetics, Dietitians of Canada and ACSM position statement supports matching carbohydrate strategies to exercise demands. The Australian Institute of Sport classifies appropriate sports foods as evidence-supported options in specific circumstances. That is not an instruction that every active person must purchase them. [3] [4]
The limitations
Performance tests range from time trials to time-to-exhaustion experiments. Starting diet, fitness, duration, formulation and gastrointestinal tolerance vary. A laboratory test where someone lasts longer cannot be translated directly into the same percentage reduction in marathon time. [1] [2]
Much of the literature concerns endurance-trained participants and specific conditions. Results do not show that more carbohydrate always produces better performance, that a proprietary gel is necessary, or that a short walk needs deliberate refuelling. [2] [3] [4]
What this means for you
Match fuelling to the session. For a long ride, run or similar endurance event, practising a tolerable carbohydrate plan can be useful; ordinary foods and sports foods can both have roles. A new product tested for the first time on race day adds avoidable uncertainty. [3] [4]
For short, easy activity, a gel is not automatically an upgrade. The useful conclusion is that fuel can improve the relevant task, rather than that everyone should consume sports products or fear exercising without them. Individual plans are best tailored with a qualified sports dietitian when demands are substantial. [3]
Research & Sources
1. Bourdas et al. (2021). Meta-Analysis of Carbohydrate Solution Intake during Prolonged Exercise in Adults. Nutrients.
Read the original source ↗2. Tarrit et al. (2026). Carbohydrate consumption during endurance exercise: systematic review of systematic reviews and meta-analyses of RCTs.
Read the original source ↗3. Thomas, Erdman and Burke (2016). Joint position statement: Nutrition and Athletic Performance.
Read the original source ↗4. Australian Institute of Sport. Sports drinks: evidence and appropriate sporting uses.
Read the original source ↗Evidence reviewed: October 2026
This targeted editorial review considered evidence available by 25 October 2026. It is not an exhaustive systematic review or independent clinical peer review. Assessment used available full texts, research abstracts and authoritative guidance; some publisher full texts were inaccessible. Evidence vs Hype provides education, not individual diagnosis or treatment. Featured artwork is AI-generated editorial illustration, not a study result or product endorsement.