Evening caffeine did not improve 100 m swimming time-trials performed 60 min post-ingestion, or the next morning after sleep

Newbury, Josh W. and Saunders, Bryan and Gough, Lewis A. (2022) Evening caffeine did not improve 100 m swimming time-trials performed 60 min post-ingestion, or the next morning after sleep. International Journal of Sports Nutrition and Exercise Metabolism. ISSN 1526-484X

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The potential ergogenic benefits of caffeine (CAF) are well known within the athletic community, often leading to its use in adolescent swimming cohorts to enhance their performance. However, it has previously been reported that CAF has sleep disturbing effects, which could be detrimental to performance over consecutive days in multi-day competitions. Moreover, the effects that evening CAF ingestion has on sleep, side-effects, and next-day performances are yet to be researched in trained adolescents. In a double-blind, randomised, crossover design, eight national-level swimmers (age:18±1 years, height: 1.76±0.06 cm, body mass: 69.4±6.4 kg) ingested a capsule containing 3 mg∙kg BM26 1 CAF or a placebo (PLA) 60 min before an evening 100 m swimming time-trial. The next morning, sleep was analysed (Core Consensus Sleep Diary) and 100 m time-trials were repeated. Side-effects were analysed via visual analogue scales (VAS) throughout the study. No differences were found for swimming performance (p=0.911) in the evening (CAF: 59.5±7.8 s, PLA: 59.9±7.9 s, g=0.06) or morning (CAF: 59.7±7.7 s, PLA: 60.2±7.9 s, g=0.07). In addition, no group differences were found for any subjective side-effects (e.g., anxiety: p=0.468; tachycardia: p=0.859; alertness: p=0.959) or sleep parameters (e.g., sleep latency: p=0.395; total sleep time: p=0.574). These results question the use of a standardised 3 mg∙kg BM-1 CAF ingestion strategy for 100 m swimming time-trials in trained adolescents, although objective measures may be needed to confirm that CAF does not affect sleep within this cohort.

Item Type: Article
Additional Information: Accepted author manuscript version reprinted, by permission, from International Journal of Sports Nutrition and Exercise Metabolism, 2022, https://doi.org/10.1123/ijsnem.2022-0042. © Human Kinetics, Inc.
Identification Number: https://doi.org/10.1123/ijsnem.2022-0042
21 May 2022Accepted
11 July 2022Published Online
Uncontrolled Keywords: adolescent athletes, sport nutrition, ergogenic aids, swimming, exercise
Subjects: CAH03 - biological and sport sciences > CAH03-02 - sport and exercise sciences > CAH03-02-01 - sport and exercise sciences
Divisions: Faculty of Health, Education and Life Sciences > Centre for Life and Sport Sciences (C-LASS)
Depositing User: Lewis Gough
Date Deposited: 24 May 2022 10:29
Last Modified: 20 Jul 2022 15:15
URI: https://www.open-access.bcu.ac.uk/id/eprint/13250

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