What the study found
The caffeine-bar condition produced a longer time to exhaustion than both comparison conditions. Some cognitive-test results also favored caffeine; this does not mean every performance measure improved.
Participants and protocol
Twenty-four trained cyclists compared a carbohydrate bar with caffeine, an energy-matched bar without caffeine, and a placebo drink. Prolonged cycling was followed by an exhaustion test; cognitive tasks were assessed repeatedly.
What this cannot establish
The tested product and prolonged-cycling protocol do not establish a universal caffeine dose or a race-time benefit for every athlete.
Publication details
- Record
- PubMed 18799996
- Publication types
- Research Support, Non-U.S. Gov't · Randomized Controlled Trial
- Indexed subjects
- Saliva · Caffeine · Blood Glucose · Central Nervous System Stimulants · Placebos
- Source record checked
- 2026-10-16
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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