REF-066 · Burke et al., 2011 · Journal of Sports Sciences, Vol. · Paper

Carbohydrates for Training and Competition: Updated Recommendations (IOC consensus review)

B+moderate evidenceMeasured on a mixed groupWritten before October 2026, being re-checked

Overview

Burke, Hawley, Wong and Jeukendrup frame an athlete's carbohydrate intake in terms of carbohydrate availability: whether total daily intake and its timing around exercise keep enough carbohydrate for the muscle and the central nervous system ("high availability") or leave carbohydrate limiting for the day's training ("low availability").

Availability is raised by carbohydrate in the hours or days before a session, intake during exercise, and refuelling between sessions; high availability matters most for competition and for high-intensity training where optimal performance is wanted. Intake during exercise should be scaled to the event.

Key Findings

Sustained high-intensity events of ~1 h: small amounts of carbohydrate, even a mouth rinse, enhance performance via central nervous system effects.
Longer events: 30-60 g/h is an appropriate target.
Events >2.5 h: may benefit from higher intakes, up to 90 g/h.
At such high rates, products blending different carbohydrates (multiple transporters) may maximise absorption.
Athletes train with varying carbohydrate availability in real life; whether deliberate "train-low" strategies improve performance in well-trained individuals is unclear.

Practical Application

Scale carbohydrate during exercise to the event (Burke et al. 2011, IOC consensus review): ~1 h of sustained high intensity — small amounts or even a mouth rinse work through the CNS; longer events — 30-60 g/h; events over 2.5 h — up to 90 g/h, using blends of different carbohydrates to absorb at that rate.
Think in terms of carbohydrate availability across the day, not only during the session: pre-session carbohydrate, intake during, and refuelling between sessions all raise it; competition and hard training want it high.
The paper does not settle "train-low": it calls the performance benefit in well-trained athletes unclear, so treat deliberate low-availability sessions as an option to test, not a rule (REF-543, REF-726).
Not from this paper; the base's own practice: rehearse race intakes on long training rides first — gut tolerance decides the usable rate, and the ≥100 g/h practised in professional racing (REF-334, REF-008) sits above this document's ranges.

Limitations

2011 consensus guidelines. Carbohydrate practice has moved substantially since — not from this paper: the ≥100 g/h range now used in professional racing (REF-334, REF-008) sits above this document's recommendations.
Guidelines synthesise evidence into ranges; they carry the authors' weighting and are not a pooled effect estimate.
Intakes framed for competition in well-trained athletes are frequently over-applied to recreational athletes training far fewer hours.
Individual gut tolerance, the binding constraint in practice, cannot be specified by any guideline and must be trained and tested (REF-008).
Says little about the interaction with deliberate carbohydrate periodisation, which postdates it (REF-543, REF-726).
How this entry was checked and changed
Why this level

regraded 2026-09-27 from A: authoritative narrative review from the leading group, not a systematic review or the consensus statement itself

Content correction 2026-09-27
"1 h effort: 30-60 g/h; 1-2.5 h: 60-75 g/h; >2.5 h: 75-90 g/h" -> abstract: ~1 h = small amounts or mouth rinse (CNS effect); longer = 30-60 g/h; >2.5 h = up to 90 g/h. The 60-75 g/h tier and the 75 g/h floor were not in the paper.
"Absorption limit ~1.5-2.0 g/min (glucose)", "training 50-75 g/h, race 80-100 g/h", ">100 g/h risks GI distress" -> not in the abstract; removed (race rehearsal kept as the base's own practice).
"Race permits higher frequency; foundational across ISSN and UCI guidelines" -> not in the abstract; removed. Added the paper's carbohydrate-availability framing and its open verdict on train-low.
Level A -> B+ (narrative review from the leading group); Tier 4-5 -> mixed; Sport running -> general.