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Increases in cycling performance in response to caffeine ingestion are repeatable.
Todd A Astorino1, Trisha Cottrell, Andrea Talhami Lozano
1Department of Kinesiology, California State University-San Marcos, San Marcos, CA, USA. astorino@csusm.edu
Caffeine consistently enhances cycling performance, improving times by approximately 1.6% in trained individuals. These ergogenic benefits are repeatable across separate testing days, though not all participants respond positively.
Area of Science:
- Sports Science
- Exercise Physiology
- Nutritional Supplementation
Background:
- Caffeine is a widely used ergogenic aid known to enhance endurance performance.
- The repeatability of caffeine's ergogenic effects in controlled exercise settings requires further investigation.
Purpose of the Study:
- To determine the repeatability of caffeine's ergogenic effects on 10-km cycling time trial performance.
- To assess if performance improvements with caffeine are consistent across separate testing sessions.
Main Methods:
- Nine endurance-trained cyclists completed three sessions under a randomized, single-blind, crossover design.
- Participants ingested either caffeine (5 mg/kg) or a placebo before a 10-km cycling time trial.
- Heart rate and rating of perceived exertion were monitored during exercise.
Main Results:
- Caffeine ingestion significantly improved cycling performance by 1.6%–1.9% compared to placebo.
- Performance improvements with caffeine were similar across the two separate testing days.
- Heart rate was elevated with caffeine, but perceived exertion remained unchanged.
Conclusions:
- Caffeine demonstrates repeatable ergogenic effects on cycling performance in endurance-trained individuals.
- Individual responses to caffeine supplementation can vary, with some participants not experiencing performance enhancement.
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