Caffeine Timing, Performance, and Side Effects In Female Athletes
Is there a trade-off if it's consumed later in the day?
This study called "Effects of Different Caffeine Dosages on Maximal Physical Performance and Potential Side Effects in Low-Consumer Female Athletes: Morning vs. Evening Administration" (PMID: 39064667) investigates how varying doses of caffeine (CAF) affect physical performance in female athletes, particularly focusing on the time of day (TOD) for consumption.
Key Points
Objective and Design
The study explored the impact of two caffeine doses (3 mg/kg and 6 mg/kg) administered at different times (morning vs. evening) on the physical performance and side effects of low-caffeine-consuming female athletes.
It employed a double-blind, randomised, and counterbalanced design involving 15 participants who underwent six trials.
Performance Tests
Athletes performed various tests: countermovement jumps (CMJ), modified agility T-test (MATT), and repeated sprint ability (RSA).
The study assessed perceived exertion (RPE) and potential side effects through questionnaires.
Findings on Performance
Morning Performance: Both caffeine doses improved performance in CMJ, MATT, and RSA when taken in the morning. The 6 mg/kg dose showed greater enhancements compared to 3 mg/kg.
Evening Performance: Neither caffeine dose improved performance in the evening compared to placebo, indicating that timing significantly affects the ergogenic effects of caffeine.
Side Effects
The occurrence of side effects increased significantly after evening caffeine ingestion, particularly with the 6 mg/kg dose. Common side effects included headaches, gastrointestinal issues, and insomnia.
In the morning, side effects were less prevalent, suggesting that morning administration may mitigate adverse effects.
Related
Practical Takeaways
Optimal Timing: Female athletes may benefit more from caffeine supplementation in the morning rather than the evening to enhance physical performance without significant side effects.
Dosage Considerations: A moderate dose of 6 mg/kg is more effective for improving short-term performance in the morning, while lower doses (3 mg/kg) may not provide the same benefits.
Monitoring Side Effects: Athletes should be aware of potential side effects, especially when consuming caffeine in the evening. It may be beneficial to limit caffeine intake close to competition or training sessions held later in the day.
Individual Variability: The study highlights the importance of individual responses to caffeine, recommending that athletes should tailor their caffeine strategies based on personal tolerance and performance goals.
Overall, the findings emphasise the significance of timing and dosage in the effective use of caffeine as an ergogenic aid for female athletes.
Reference
Bougrine H, Ammar A, Salem A, Trabelsi K, Żmijewski P, Jahrami H, Chtourou H, Souissi N. Effects of Different Caffeine Dosages on Maximal Physical Performance and Potential Side Effects in Low-Consumer Female Athletes: Morning vs. Evening Administration. Nutrients. 2024 Jul 11;16(14):2223. doi: 10.3390/nu16142223. PMID: 39064667; PMCID: PMC11279619.