ArticleScientific reports2020
Gold, silver or bronze: circadian variation strongly affects performance in Olympic athletes.
Article in Scientific reports, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 27 papers, 1 of them a synthesis that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
27 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Influence of time-of-day on neuromuscular performance in team sport athletes: a systematic review and meta-analysis.Frontiers in sports and active living · 2024Pooled it
- Effects of Acute Caffeine Ingestion on Morning Temperature, Mood, Reactive Agility and Cognitive Measures in Males: A Standardized Approach.Nutrients · 2026Trial
- Effects of Acute Caffeine Ingestion on Morning Strength, Power and Repeated Sprint Measures in Males: A Standardized Approach.Nutrients · 2026Trial
- Effects of 8 Weeks of 2S-Hesperidin Supplementation on Performance in Amateur Cyclists.Nutrients · 2020Trial
- Home-Court Advantage and the Associations of Travel and Jet Lag with Team Performance in the Women's National Basketball Association (WNBA).Sports medicine - open · 2026Article
- Circadian biology and exercise: the time to move.Life metabolism · 2026Review
- Optimizing Athlete Travel for Performance: A Scientific Blueprint for Athletes, Coaches, and Sports Medicine Staff.Sports medicine (Auckland, N.Z.) · 2026Review
- The effect of timing of physical exercise on glycemia: a systematic review and meta-analysis of human intervention studies.Journal of diabetes and metabolic disorders · 2026Review
- Exercise Timing in Sport: Molecular and Physiological Mechanisms Linking Performance, Recovery, and Biological Cost.International journal of molecular sciences · 2026Review
- Travel-Induced Circadian and Microbiota Disturbances: Implications for Athlete Health and Performance: A Narrative Review.Nutrients · 2026Review
- Circadian misalignment and adolescent obesity risk behaviors: physical & sedentary activity, dietary intake, and food reward.Sleep advances : a journal of the Sleep Research Society · 2026Article
- Time to Reset: The Interplay Between Circadian Rhythms and Redox Homeostasis in Skeletal Muscle Ageing and Systemic Health.Antioxidants (Basel, Switzerland) · 2025Review
- Circadian Regulation for Optimizing Sport and Exercise Performance.Clocks & sleep · 2025Review
- Diurnal variation in skeletal muscle mitochondrial function dictates time-of-day-dependent exercise capacity.FASEB journal : official publication of the Federation of American Societies for Experimental Biology · 2025Article
- The effect of time of day on anaerobic performance and blood lactate response in trained men: assessment in relation to chronotype.Frontiers in physiology · 2025Article
- The Negative Effects of Travel on Student Athletes Through Sleep and Circadian Disruption.Journal of biological rhythms · 2024Article
- The molecular athlete: exercise physiology from mechanisms to medals.Physiological reviews · 2023Review
- Enhancing the metabolic benefits of exercise: Is timing the key?Frontiers in endocrinology · 2023Review
- Article
- Daily running enhances molecular and physiological circadian rhythms in skeletal muscle.Molecular metabolism · 2022Article
Corrections and comments
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Authors and funding
5 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The circadian system affects physiological, psychological, and molecular mechanisms in the body, resulting in varying physical performance over the day. The timing and relative size of these effects are important for optimizing sport performance. In this study, Olympic swim times (from 2004 to 2016) were used to determine time-of-day and circadian effects under maximal motivational conditions. Data of athletes who made it to the finals (N = 144, 72 female) were included and normalized on individual levels based on the average swim times over race types (heat, semifinal, and final) per individual for each stroke, distance and Olympic venue. Normalized swim times were analyzed with a linear mixed model and a sine fitted model. Swim performance was better during finals as compared to semi-finals and heats. Performance was strongly affected by time-of-day, showing fastest swim times in the late afternoon around 17:12 h, indicating 0.32% improved performance relative to 08:00 h. This study reveals clear effects of time-of-day on physical performance in Olympic athletes. The time-of-day effect is large, and exceeds the time difference between gold and silver medal in 40%, silver and bronze medal in 64%, and bronze or no medal in 61% of the finals.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.