What the study found
Carbohydrate reduced the menstrual-phase difference in circulating leukocytes, but neither beverage nor menstrual phase significantly changed the final performance test.
Participants and protocol
Six healthy women completed four hot-environment cycling trials combining menstrual phase and carbohydrate or placebo beverages, with immune and physiological measurements.
What this cannot establish
Changes in blood-cell counts do not demonstrate prevention of infection. The small study cannot support universal phase-based fueling rules or a promised performance improvement.
Publication details
- Record
- PubMed 25342934
- Publication types
- research-article
- 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.
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