Abstract
Purpose:
This study conducted a bibliometric analysis of the literature on circadian rhythms and sports to identify research trends, knowledge gaps, and future directions.
Methods:
A total of 301 manuscripts, including 245 articles and 56 reviews, were extracted from the Web of Science Core Collection (WoSCC) database, and the bibliometric analysis was performed using VOSviewer 1.6.16.
Results:
The analysis revealed a continuous increase in the volume of literature on circadian rhythms and sports over the past 38 years, with a focus on the effects of circadian rhythms on physical performance, sleep quality, and jet lag. The study identified 1107 authors who have contributed to this field, with the highest number of publications from Reilly T, Chtourou H, and Atkinson G. The publications were from 512 institutions in 59 countries/regions, with Liverpool John Moores University, University of Sfax, and Manouba University being the leading institutions. The USA, UK, and Australia had the largest number of publications. The top 3 journals were Chronobiology International, Biological Rhythm Research, and Sports Medicine.
Conclusion:
Despite the increase in research, there are still several underexplored areas, such as the effects of circadian rhythms on cognitive and emotional processes in sports, the role of individual differences in circadian rhythms on sports outcomes, and the potential applications of circadian interventions for sports performance optimization. Future research should address these gaps to advance our understanding of the complex relationship between circadian rhythms and sports.
Keywords: bibliometric analysis, circadian rhythm, sport, visual maps, VOSviewer
1. Introduction
Circadian rhythm refers to the endogenous biological oscillations that occur in almost all living organisms with a period of approximately 24 hours.[1] The suprachiasmatic nucleus, which is situated in the hypothalamus, serves as the central circadian clock responsible for generating these rhythms, which is synchronized by external cues, such as light-dark cycles, meal timing, and social interactions.[2] Circadian rhythm plays a critical role in regulating various physiological and behavioral processes, including sleep-wake cycles, hormone secretion, metabolism, and immune function.[3] Disruptions to circadian rhythm, such as those caused by shift work, jet lag, or sleep disorders, can have detrimental effects on health and well-being, including increased risks of metabolic disorders, cardiovascular diseases, and mood disorders.[4,5] Understanding circadian rhythm is crucial as it governs various physiological and behavioral processes, including sleep-wake cycles, hormone secretion, metabolism, and immune function. Researching circadian rhythm provides a broader perspective on the regulation of these processes and allows for a comprehensive understanding of health outcomes. Focusing on circadian rhythm rather than solely studying sleep helps uncover the intricate interplay between biological rhythms and overall well-being, shedding light on the impact of disruptions on various aspects of health beyond sleep alone.
In recent years, the influence of circadian rhythm on sports performance, injury risk, and recovery has attracted growing attention from researchers, coaches, and athletes.[6] The timing and intensity of physical activity, as well as the quality and quantity of sleep and rest, are closely linked to circadian rhythm, and can affect sports outcomes in various ways.[7] For example, research suggests that the time of day can have significant effects on physical performance, with peak performance typically occurring in the late afternoon or early evening when body temperature and cortisol levels are at their highest.[8] In contrast, performance is typically lowest in the early morning, when body temperature and cortisol levels are at their lowest.[9] Similarly, sleep quality and quantity are critical factors for sports performance and recovery, and disruptions to circadian rhythm can impair sleep and increase injury risk.[10]
Bibliometric analysis offers several unique advantages in research evaluation and knowledge mapping. It allows for a quantitative assessment of research productivity, impact, and collaboration patterns, providing a comprehensive overview of the field. Compared to other review types such as systematic reviews and meta-analyses, bibliometric analysis focuses on analyzing publication and citation patterns, identifying research hotspots, and mapping the intellectual structure of a specific field. It provides valuable insights into research trends, influential authors, institutions, and journals, which can help researchers and policymakers make informed decisions. While systematic reviews and meta-analyses synthesize existing evidence to answer specific research questions, bibliometric analysis provides a broader perspective by examining the overall research landscape. It complements qualitative analyses and can reveal emerging topics, collaborations, and knowledge gaps that may require further investigation.[11]Despite the growing interest in circadian rhythm and sports, there is still much to be learned about this complex topic. The aim of this paper is to perform a bibliometric analysis of the literature on circadian rhythm and sport performance to offer a thorough summary of the research trends, knowledge gaps, and future directions in this area.
2. Materials and methods
2.1. Search strategy
Web of Science (WoS) is widely recognized as a reliable academic database. It undergoes rigorous data quality control, including manual indexing and citation verification, ensuring the accuracy and reliability of the provided literature information. WoS is extensively utilized in bibliometric research across various disciplines and is considered the gold standard for academic research evaluation. Its longstanding reputation and researchers’ familiarity have made it the preferred choice for bibliometric analysis. Choosing WoS enables better comparability and benchmarking against existing literature, providing researchers with a broader range of references. Moreover, WoS offers a wealth of literature information and analysis tools that support our research objectives. Through WoS, we can access detailed citation data, understand the development trends of the research field, identify highly cited documents, and analyze the distribution of authors, institutions, and journals. These insights are valuable for uncovering research hotspots, identifying emerging topics, and constructing scientific knowledge maps. Therefore, we obtained literature on sport and circadian rhythms from WoSCC. The mesh subject term list contained relevant subject terms and free terms pertaining to both sport and circadian rhythms, which were subsequently combined to conduct the search. The search terms for circadian rhythms were “Circadian Rhythm” or “Circadian Rhythms” or “Rhythm, Circadian” or “Rhythms, Circadian” or “Twenty-Four Hour Rhythm” or “Rhythm, Twenty-Four Hour” or “Rhythms, Twenty-Four Hour” or “Twenty Four Hour Rhythm” or “Twenty-Four Hour Rhythms” or “Nyctohemeral Rhythm” or “Nyctohemeral Rhythms “or “Rhythm, Nyctohemeral “or “Rhythms, Nyctohemeral “or “Nycthemeral Rhythm “or “Nycthemeral Rhythms “or “Rhythm, Nycthemeral “or “Rhythms, Nycthemeral” or “Diurnal Rhythm” or “Diurnal Rhythms” or “Rhythm, Diurnal” or “Rhythms, Diurnal.” The search terms for sports are “Sports” or “Sport” or “Athletics” or “Athletic.” The search terms were linked by AND. The search period was from January 1, 1985 to December 31st, 2022. The language was limited to English and the type of literature was limited to articles and reviews.
2.2. Data collection and analysis
The documents that were retrieved were exported in “Plain Text” format, with the record content being set to “Full Record and Cited References.”A bibliometric analysis was performed on the acquired literature. The characteristics of the literature related to sport and circadian rhythms were summarized in terms of author, institution, country, journal and citation frequency.
VOSviewer is a bibliometric analysis tool used to visualize and analyze scientific literature networks. By using its default parameter settings, researchers can conduct a comprehensive analysis. VOSviewer automatically processes the input bibliographic data, identifies relevant terms, calculates term occurrences, performs term co-occurrence analysis, clusters similar terms, and generates visualizations. These default settings ensure a balanced and informative analysis, enabling researchers to explore patterns, relationships, and key insights within the literature network.
In terms of technical details, VOSviewer primarily focuses on co-occurrence analysis and clustering based on term relationships within the bibliographic data. It calculates the strength of associations between terms and employs algorithms to generate clusters based on these associations. VOSviewer offers visualization options that allow customization of colors, sizes, and layouts to enhance the clarity of network representation.
3. Results
3.1. Publication output trend
In this study, a total of 301 publications (comprising 245 articles and 56 reviews) were analyzed, as shown in Figure 1. The quantity of literature pertaining to exercise and circadian rhythms exhibited a rising trend, as illustrated in Figure 2. A significant upward trend was observed in 2021 and 2022, which may be attributed to the impact of the COVID-19 pandemic.
Figure 1.
Flowchart of documents screening.
Figure 2.
Trend of publications on sport and circadian rhythms from 1985 to 2022.
3.2. Distribution of authors
In total, 1107 authors have made contributions to this field. The top 10 authors with the most publications are presented in Table 1. The most prolific author in terms of publications was Reilly T who had a total of 17 papers to their credit, followed by Chtourou H with 14 publications, Atkinson G with 13 publications, Souissi N with 12 publications, and Waterhouse J with 11 publications. The top 10 authors with the highest number of citations are presented in Table 2. Reilly T emerged as the most productive author, with a total of 1854 citations to their name, followed by Atkinson G with 1551 citations, Waterhouse J with 1145 citations, Edwards B with 1133 citations, and Davenne D with 294 citations. Figure 3 displayed the co-authorship network among the authors.
Table 1.
Top 10 authors ranked by the number of publications.
| Ranking | Authors | Documents |
|---|---|---|
| 1 | Reilly T | 17 |
| 2 | Chtourou H | 14 |
| 3 | Atkinson G | 13 |
| 4 | Souissi N | 12 |
| 5 | Waterhouse J | 11 |
| 6 | Edwards B | 8 |
| 7 | Piccione G | 8 |
| 8 | Davenne D | 6 |
| 9 | Fazio F | 6 |
| 10 | Vitale JA | 6 |
Table 2.
Top 10 Authors with the highest number of citations.
| Ranking | author | citations |
|---|---|---|
| 1 | Reilly T | 1854 |
| 2 | Atkinson G | 1551 |
| 3 | Waterhouse J | 1145 |
| 4 | Edwards B | 1133 |
| 5 | Davenne D | 294 |
| 6 | Chtourou H | 226 |
| 7 | Souissi N | 152 |
| 8 | Lopez-samanes A | 125 |
| 9 | Hill DW | 54 |
| 10 | Silva A | 30 |
Figure 3.
The co-authorship of authors.
3.3. Distribution by institution
A total of 512 institutions have published literatures related to sport and Circadian rhythm. The leading institutions are Liverpool John Moores University (21 publications, 1621 citations), University of Sfax (9 publications, 100 citations), Manouba University (7 publications, 132 citations), National Centre of Medicine and Science in Sports (7 publications, 109 citations), University of Calgary (7 publications, 250 citations). Table 3 presented the top 10 institutions that had the highest number of publications. The co-authorship of institution was shown in Figure 4.
Table 3.
Top 10 Institutions with the highest number of publications.
| Ranking | Institution | Documents | Citations | Total link strength |
|---|---|---|---|---|
| 1 | Liverpool John Moores University | 21 | 1621 | 4 |
| 2 | University of Sfax | 9 | 100 | 11 |
| 3 | Manouba University | 7 | 132 | 6 |
| 4 | National Centre of Medicine and Science in Sports (CNMSS) | 7 | 109 | 6 |
| 5 | University of Calgary | 7 | 250 | 9 |
| 6 | University of California San Diego | 6 | 324 | 1 |
| 7 | Federal University of Minas Gerais | 6 | 41 | 2 |
| 8 | University of Messina | 6 | 101 | 2 |
| 9 | University of Milan | 6 | 99 | 5 |
| 10 | Central Queensland University | 5 | 67 | 1 |
Figure 4.
The co-authorship map of institutions.
3.4. Distribution by country/region
Table 4 provided a list of the top 10 countries with the highest number of publications. The countries with the highest number of publications was the United States (76 documents, 2488 citations), followed by the United Kingdom (52 documents, 2375 citations), Australia (34 documents, 953 citations), Italy (29 documents, 667 citations), and France (26 documents, 792 citations). Figure 5 depicted the network visualization map of the country/region.
Table 4.
Top 10 Countries by number of publications.
| Ranking | Country | Documents | Citations | Total link strength |
|---|---|---|---|---|
| 1 | United States | 76 | 2488 | 61 |
| 2 | United Kingdom | 52 | 2375 | 54 |
| 3 | Australia | 34 | 953 | 51 |
| 4 | Italy | 29 | 667 | 39 |
| 5 | France | 26 | 792 | 48 |
| 6 | Tunisia | 22 | 361 | 30 |
| 7 | Germany | 21 | 1269 | 27 |
| 8 | Brazil | 16 | 140 | 23 |
| 9 | Spain | 16 | 536 | 22 |
| 10 | Canada | 14 | 534 | 29 |
Figure 5.
The co-authorship map of countries/regions.
3.5. Distribution by journal
The included documents were from 134 journals. Chronobiology International was the most productive journal with 36 publications and 1425 citations, which was followed by Biological Rhythm Research with 15 publications and 178 citations, Sports Medicine with 12 publications and 1379 citations, and International Journal of Sports Medicine with 11 publications and 280 citations, and Journal of strength and conditioning research with 11 publications and 211 citations. Table 5 presented the top 10 journals with the highest number of publications, while Figure 6 depicted the network visualization map of all the journals.
Table 5.
Top 10 Journals ranked by number of publications.
| Ranking | Journal | Documents | Citations | Total link strength |
|---|---|---|---|---|
| 1 | Chronobiology International | 36 | 1425 | 131 |
| 2 | Biological Rhythm Research | 15 | 178 | 48 |
| 3 | Sports Medicine | 12 | 1379 | 110 |
| 4 | International Journal of Sports Medicine | 11 | 280 | 36 |
| 5 | Journal of Strength and Conditioning Research | 11 | 211 | 48 |
| 6 | European Journal of Applied Physiology | 9 | 400 | 60 |
| 7 | Journal of Science and Medicine in Sport | 8 | 212 | 14 |
| 8 | Journal of Sports Sciences | 8 | 305 | 55 |
| 9 | International Journal of Sports Physiology and Performance | 7 | 198 | 19 |
| 10 | Medicine and Science in Sports and Exercise | 6 | 449 | 29 |
Figure 6.
Visualization map of journal citations.
3.6. Analysis of high cited documents
Table 6 lists the top 20 most frequently cited publications. The most frequently cited article was published in Chronobiology International by Drust et al In this review article they provide an overview of the current state of knowledge on the relationship between circadian rhythms and sports performance. The article covers topics such as the impact of the circadian rhythm on physical performance, injury risk, and recovery in athletes. It also discusses the importance of sleep and the role of external and internal cues, such as light and hormones, in regulating the circadian rhythm. Additionally, the article highlights the challenges posed by international travel and nighttime competitions on athlete circadian rhythms and performance. Finally, the article emphasizes the need for further research to better understand the influence of circadian rhythms on sports performance and the development of strategies to optimize athlete circadian rhythms. The 2nd most frequently cited paper was published in Sports Medicine by Fullagar et al This review article discussed the effects of sleep loss on sport performance, physiological responses, and cognitive responses in athletes. The article highlights the importance of adequate sleep for optimal athletic performance and recovery, and describes the negative impacts of sleep deprivation on various aspects of athletic performance. The authors also provide recommendations for optimizing sleep for athletes, including strategies for improving sleep quantity and quality. Overall, the article emphasizes the significant role that sleep plays in athletic performance and the need for athletes to prioritize sleep as a crucial component of their training and recovery regimens. The 3rd most frequently cited paper was published in Sports Medicine by Atkinson. This article discusses the impact of circadian rhythms on athletic performance. The authors reviewed studies examining the relationship between the time of day and performance in various sports, such as swimming, running, and weightlifting. They found that there is a circadian variation in performance, with optimal performance occurring in the late afternoon and early evening. The authors also discuss the potential implications for scheduling training and competitions based on an athlete circadian rhythm. Overall, the article highlights the importance of considering circadian rhythms in sports performance and training. The visualization map of the document citation network can be seen in Figure 7.
Table 6.
Top 20 highly cited documents.
| Ranking | Title | Journal | Citation | Yr |
|---|---|---|---|---|
| 1 | Circadian rhythms in sports performance - An update | Chronobiology International | 373 | 2005 |
| 2 | Sleep and Athletic Performance: The Effects of Sleep Loss on Exercise Performance, and Physiological and Cognitive Responses to Exercise | Sports Medicine | 366 | 2015 |
| 3 | Circadian Variation in sports performance | Sports Medicine | 343 | 1996 |
| 4 | The Effects of Sleep Extension on the Athletic Performance of Collegiate Basketball Players | Sleep | 302 | 2011 |
| 5 | Hypoleptinemia in women athletes: Absence of a diurnal rhythm with amenorrhea | Journal of Clinical Endocrinology & Metabolism | 287 | 1997 |
| 6 | Current Status of Salivary Hormone Analysis | Clinical Chemistry | 244 | 2008 |
| 7 | The circadian rhythm of core temperature: Origin and some implications for exercise performance | Chronobiology International | 176 | 2005 |
| 8 | The thermophysiology of uncompensable heat stress - Physiological manipulations and individual characteristics | Sports Medicine | 176 | 2000 |
| 9 | Altered sleep-wake cycles and physical performance in athletes | Physiology & Behavior | 173 | 2007 |
| 10 | Circadian-rhythms and Athletic performance | Medicine & Science in Sports & Exercise | 172 | 1985 |
| 11 | Sleep, circadian rhythms, and psychomotor vigilance | Clinics in Sports Medicine | 169 | 2005 |
| 12 | Circadian rhythm of wrist temperature in normal-living subjects A candidate of new index of the circadian system | Physiology & Behavior | 149 | 2008 |
| 13 | Investigation of morning-evening orientation in 6 countries using the preferences scale | Personality and Individual Differences | 147 | 2002 |
| 14 | Exercise, energy balance and the shift worker | Sports Medicine | 141 | 2008 |
| 15 | Relation between physical training and ambulatory blood pressure in stage-i hypertensive subjects - results of the harvest trial | Circulation | 128 | 1994 |
| 16 | Scheduled Exercise Phase Shifts the Circadian Clock in Skeletal Muscle | Medicine & Science in Sports & Exercise | 127 | 2012 |
| 17 | Sleep, recovery, and performance: The new frontier in high-performance athletics | Neurologic Clinics | 127 | 2008 |
| 18 | Sleep, circadian rhythms, and athletic performance | Sleep Medicine Reviews | 123 | 2015 |
| 19 | Hypothalamic-pituitary-thyroidal function in eumenorrheic and amenorrheic athletes | Journal of Clinical Endocrinology & Metabolism | 123 | 1992 |
| 20 | Sleep habits in German athletes before important competitions or games | Journal of Sports Sciences | 119 | 2011 |
Figure 7.
Visualization knowledge maps of highly cited documents.
3.7. Analysis of all keywords co-occurrence clusters
The network visualization map of all keywords was illustrated in Figure 8. The different colors represented the different research focus directions. The size of the nodes reflects the frequency of keyword occurrences. All keywords form 4 clusters. The keywords in the red cluster were shift work, deprivation, daytime sleepiness, health, alertness, anxiety. The keywords in the yellow cluster were air-travel, flight, jet-lag and time zones.The keywords in the green cluster were chronotype, morningness-eveningness, diurnal variation, body-temperature and core-temperature. The keywords in the blue clusters were time of day, skeletal-muscle, training, heart-rate-variablity and strength.
Figure 8.
Visualization of co-occurrence analysis for keywords.
4. Discussion
4.1. General information
This is the first-ever bibliometric study conducted on research concerning the intersection of sport and circadian rhythms. In total, 301 publications were reviewed as part of this analysis, of which 245 were articles and 56 were review. Our bibliometric analysis revealed a noticeable increase in the volume of literature related to sport and circadian rhythms. In total, 1107 authors were identified as having contributed to this area of research. Reilly T., Chtourou H., and Atkinson G. were found to be the authors with the most publications, while Reilly T, Atkinson G, and Waterhouse J were identified as the most highly cited authors. All publications are published by about 512 institutions in 59 countries/regions. The leading institutions are Liverpool John Moores University, University of Sfax and Manouba University. Our analysis found that all the publications on sport and circadian rhythms were published in a total of 134 journals, with the most prolific ones being Chronobiology International, Biological Rhythm Research, and Sports journals. The highest cited reference was published in Chronobiology international, which was cited 373 times by Drust et al The keyword clustering shows 4 research directions. The keywords in the red cluster were shift work, deprivation, daytime sleepiness, health, alertness, anxiety. The keywords in the yellow cluster were air-travel, flight, jet-lag and time zones. The keywords in the green cluster were chronotype, morningness-eveningness, diurnal variation, body-temperature and core-temperature. The keywords in the blue clusters were time of day, skeletal-muscle, training, heart-rate-variablity and strength. Muscle mass can serve as a reliable predictive factor for the occurrence of sleep issues in both the general population and athletes. Maintaining a certain level of muscle mass is beneficial for sleep health.[12]
4.2. Research trends, knowledge gaps, and future directions
Our analysis of the bibliometric data reveals a dominant focus on the influence of external cues, particularly light, on circadian rhythms in sports. This is consistent with previous research highlighting the importance of light as the primary zeitgeber for the human circadian system.[13] Light exposure has been found to have significant effects on various aspects of athletic performance, including sleep, alertness, and cognitive function, as well as on physiological processes such as hormone secretion and metabolism.[14] Our findings suggest that this remains a highly active area of research, with a continued emphasis on investigating the effects of light exposure on athletic performance and developing strategies to optimize training and competition schedules accordingly.
However, our analysis also revealed a notable gap in the literature regarding the influence of internal cues, such as hormones, on the circadian rhythm in sport. While some studies have examined the effects of hormones such as melatonin and cortisol on athletic performance and recovery,[15,16] there remains a need for further research in this area. Specifically, future studies could investigate how internal cues interact with external cues to influence athletic performance and recovery, as well as how individual differences in circadian biology may impact these processes.
Overall, our analysis highlights the need for a more comprehensive understanding of the role of both internal and external cues in regulating the circadian rhythm in sport. By integrating both types of cues into training and competition schedules, athletes and coaches may be able to optimize performance, reduce injury risk, and improve recovery outcomes.
In addition to the focus on external cues and their influence on circadian rhythms in sports, our bibliometric analysis also revealed a growing interest in the impact of circadian rhythms on athletic performance and injury risk in team sports. This is a particularly important area of research given the unique demands and challenges of team sports, such as frequent travel, irregular game schedules, and variations in playing time.
Previous studies have shown that circadian disruptions due to factors such as jet lag and shift work can have negative effects on athletic performance and increase the risk of injury.[17,18] In team sports, where multiple players are involved and coordination and communication are crucial, circadian disruptions can potentially have even greater consequences.
Our analysis found that studies examining the impact of circadian rhythms on team sports focused on a range of sports, including basketball, soccer, ice hockey, and rugby. Some studies investigated the influence of circadian rhythms on specific aspects of team sports, such as reaction time and decision-making ability, while others examined the effects of travel and game schedules on circadian rhythms and athletic performance.[19–21]
However, there is still a need for more research to fully understand the complex interplay between circadian rhythms and team sports. Specifically, future studies could investigate the role of individual differences in circadian rhythms among athletes, such as morningness-eveningness preference, and how these differences may impact performance and injury risk in team sports. In addition, there is a need for practical interventions and guidelines for coaches and athletes to help mitigate the negative effects of circadian disruptions in team sports. Furthermore, referring to several cutting-edge studies, it should be noted that the impact of short sleep duration, insomnia, and sleep disorders on athletic performance and sleep health is remarkably significant.[22,23]
Overall, the growing interest in the impact of circadian rhythms on team sports highlights the need for continued research in this area to help inform best practices for optimizing athletic performance and reducing the risk of injury in these demanding and dynamic sports.
Our analysis revealed several emerging topics in circadian rhythm and sport research that highlight the growing interest in this field. One of these topics is the impact of sleep deprivation and circadian misalignment on athletic performance. Sleep is a critical component of athletic performance, and disruptions to sleep can have negative effects on cognitive function, mood, and physical performance.[10] Sleep deprivation can also affect the timing of the circadian rhythm, potentially leading to circadian misalignment and further impairments in performance.[24]
Another emerging topic in the field is the use of circadian interventions to improve athletic performance and recovery. Several recent studies have investigated the effectiveness of various circadian interventions, such as bright light exposure, melatonin supplementation, and time-restricted feeding, on improving athletic performance and recovery.[25,26] These interventions aim to manipulate the timing and amplitude of the circadian rhythm to enhance physical and cognitive performance and improve recovery from training and competition.
Overall, these emerging topics highlight the potential for circadian rhythm research to inform the development of new strategies for enhancing athletic performance and improving recovery in athletes. As the understanding of the role of circadian rhythms in sports continues to grow, further research in these areas is likely to be a key focus for future investigations.
4.3. Potential future research areas and recommendations
Investigate the role of internal cues: Further research is needed to understand the influence of internal cues, such as hormones, on the circadian rhythm in sport. Studies could explore how hormones interact with external cues to impact athletic performance and recovery. Additionally, examining individual differences in circadian biology and their effects on internal cues could provide valuable insights.
Explore the impact of circadian disruptions in team sports: Given the unique challenges of team sports, research should focus on understanding the consequences of circadian disruptions in these contexts. Investigate the effects of jet lag, shift work, travel, and irregular game schedules on circadian rhythms, athletic performance, and injury risk in team sports.
Examine the relationship between sleep and circadian rhythms in athletic performance: Further investigate the impact of sleep deprivation, insomnia, and sleep disorders on athletic performance and sleep health. Explore the role of circadian misalignment resulting from sleep disturbances and its effects on cognitive function, mood, and physical performance.
Develop practical interventions and guidelines: Conduct research to develop practical interventions and guidelines for coaches and athletes to mitigate the negative effects of circadian disruptions in team sports. This could involve strategies for optimizing sleep, managing travel schedules, and adjusting training and competition schedules to align with circadian rhythms.
Investigate the effectiveness of circadian interventions: Explore the efficacy of circadian interventions, such as bright light exposure, melatonin supplementation, and time-restricted feeding, in improving athletic performance and recovery. Assess the impact of manipulating the timing and amplitude of the circadian rhythm on physical and cognitive performance in athletes.
Analyze the impact of individual differences: Study the role of individual differences in circadian rhythms, such as morningness-eveningness preference, on athletic performance and injury risk. Examine how these differences interact with external and internal cues and their implications for training, competition, and recovery strategies.
Understand the relationship between circadian rhythm and mental health: Investigate the connection between circadian rhythm disruptions, such as irregular sleep patterns, and mental health issues among athletes. Explore the impact of circadian interventions on mental health outcomes and overall well-being in the sporting context.
Conduct longitudinal studies: Longitudinal studies could provide insights into the long-term effects of circadian disruptions on athletic performance, injury risk, and overall health. Follow athletes over an extended period to assess changes in circadian rhythms, performance outcomes, and injury incidence.
Utilize advanced technologies: Explore the integration of wearable devices and other advanced technologies to monitor and optimize circadian rhythms in athletes. Investigate the potential of personalized circadian interventions based on real-time monitoring and feedback.
Enhance interdisciplinary collaborations: Foster collaboration between researchers from various disciplines, including sleep science, chronobiology, sports medicine, and performance psychology. Interdisciplinary approaches can provide a comprehensive understanding of the complex interactions between circadian rhythms and sport.
These recommendations aim to address the identified knowledge gaps and further advance the understanding of circadian rhythm in sport. By exploring these research areas, researchers can contribute to the development of evidence-based strategies for optimizing athletic performance, reducing injury risk, and improving overall well-being in sports.
5. Strengths and limitations
This paper presents a bibliometric analysis of publications on sport and circadian rhythms, which provides a comprehensive overview of the current state and trends in this field through visual maps. This study serves as a reference for future research. However, it is important to note that our analysis is limited by the fact that only documents from the WoSCC database were included and publications in languages other than English were not considered.
6. Conclusion
In conclusion, this bibliometric analysis presents a comprehensive overview of the current status and emerging trends in research related to circadian rhythms and sport. Our analysis highlights the importance of external cues, particularly light, in regulating circadian rhythms in sport, while also identifying a need for further research on the role of internal cues, such as hormones. We also identify emerging topics in this field, including the impact of sleep deprivation and the use of circadian interventions, which are likely to become increasingly important areas of research in the future.
Author contributions
Formal analysis: Jie Wang.
Funding acquisition: Lina Xia.
Investigation: Jie Wang.
Methodology: Jie Wang.
Resources: Jie Wang.
Software: Jie Wang.
Supervision: Lina Xia.
Validation: Jie Wang.
Visualization: Jie Wang.
Writing – original draft: Jie Wang.
Writing – review & editing: Jie Wang.
Abbreviation:
- WoSCC
- Web of Science Core Collection
This work was supported by the Key Research and Development Project of Science & Technology Department of Sichuan Province (No. 2020YFS0302).
The datasets generated during and/or analyzed during the current study are publicly available.
The authors have no conflicts of interest to disclose.
This article does not need an ethics statement.
How to cite this article: Wang J, Xia L. Investigation of effects of Circadian Rhythm in Sport: A bibliometric analysis. Medicine 2023;102:51(e34229).
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