What the study found
Carbohydrate before, during, or both before and during exercise increased total work and time to exhaustion compared with no carbohydrate; the combination produced the largest reported gain.
Participants and protocol
Nine trained cyclists completed prolonged cycling at a fixed relative intensity under four feeding conditions.
What this cannot establish
This 1991 exhaustion experiment does not translate its percentage gains directly into race-time savings. It supports the relevance of fuel availability, not one universal modern fueling schedule.
Publication details
- Record
- PubMed 1757304
- Publication types
- Research Support, Non-U.S. Gov't
- Indexed subjects
- Muscles · Glycerol · Lactates · Insulin · Dietary Carbohydrates
- Source record checked
- 2026-10-18
Publication type and subject indexing describe the record; they are not a quality grade or proof of a benefit. An abstract does not replace a review of the full methods and results.
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Performance Science Lab
Research summaries for endurance athletes, with study context, practical protocols, and clear limitations.
Open guideFueling performance research
Fueling is performance, not just health: the right carbs at the right time change outcomes.
Open guideTime to exhaustion research for endurance athletes
A lab outcome that can still guide training: it often tracks fatigue resistance.
Open guide