COMMUNICATION | doi:10.20944/preprints202210.0124.v1
Subject: Medicine & Pharmacology, Sport Sciences & Therapy Keywords: microbiome; skin microbiome; sports recovery; sports performance; cosmetics
Online: 10 October 2022 (11:13:00 CEST)
This short communication reports on the initial results of a much larger, ongoing project, the aim of which is to investigate the question: could the skin microbiome, just like the gut microbiome, play a role in sports recovery and performance – and if so, could this role be as significant a one as that played by the gut microbiome? 17 high performance college athletes addressed their skin microbiome by minimizing contact with synthetic chemicals and by using topical skin supplements, shown previously to significantly increase skin microbiome biodiversity, for two weeks after training. 76% said their skin softness improved, 35% said their muscle stiffness and recovery after sport improved, 12% said their sleep quality improved, and 100% said they would be likely to use skin supplements again. Future work will use hundreds of athletes.
REVIEW | doi:10.20944/preprints202202.0287.v1
Subject: Medicine & Pharmacology, Sport Sciences & Therapy Keywords: integration of sports and health care; sports; health; community
Online: 23 February 2022 (07:06:51 CET)
(1) Background: With continuous globalization and modernization of people's lives, lifestyle has changed dramatically, with decreased physical activity and increased unhealthy eating patterns in many nations throughout the world. With the COVID-19 pandemic and changes taking place in people’s health and lifestyles around the world, the need for rehabilitation is expected to rise in the coming years.(2)Methods: This paper analyzes the integration model of sports and health care using theoretical analysis, literature reviews, logical reasoning, and other methods.(3)Results: The integration of sports and health care in China has entered the stage of practical implementation after many years of development, forming a few representative integration patterns. Governments, communities, community hospitals, hospitals, and third-party institutions are the main participants, with the community playing an important role in the integration. Pharmacies, sports venues, and schools with sufficient staff have a relatively low participation rate.(4)Conclusion: The grading treatment has been applied in health management and sports rehabilitation, based on the development of digital medicine, a government-led grading treatment model of "health management center" can promote the participation of multiple subjects in the integration of sports and health care, solving the problems existing in the current integration process to a certain extent.
BRIEF REPORT | doi:10.20944/preprints202102.0105.v1
Online: 3 February 2021 (10:08:07 CET)
Top performance in team sports attracts the attention from the general public. In particular, the best players became incredibly skilled and physically powerful, a fact that potentiates to deliver a product considered attractive, exciting and competitive. Not surprisingly, this is a very valuable product from an economic and social standpoint, thus, all sports professionals are extremely interested in developing new procedures to improve sports performance. Besides, the great interests of the various stakeholders (owners, CEO-s, agents, fans, media, coaches, players, families and friends) are one of the main reasons for this development of sports science umbrella and the accompanying sports industry. all their personal performances should be coordinated and put into function by the sports team. In this scientific and applied manuscript, we will deal primarily with the individual treatment of players in order to improve their personal performance and, consequently, team sport performance.
ARTICLE | doi:10.20944/preprints202301.0258.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: Sports Nutrition; Dietary Supplements; Athletic Performance
Online: 16 January 2023 (01:29:53 CET)
The aim of the present study was to investigate the acute effect of caffeine supplementation on performance in official soccer matches. In double-blind, randomized crossover design, 13 professional soccer players performed two complete matches, with Caffeine (CAF) (6 mg/kg) and placebo (PLA) supplementation. Two-way repeated measures ANOVA showed that there was no effect of supplementation on the total distance covered (p = 0.536; ŋp² =0.033) or the total distance covered at different speeds (p = 0.453; ŋp² = 0.048), acceleration or deceleration (p = 0.387; ŋp² = 0.063) number of sprints (p = 0.521; µ² = 0.035) Heart Rate mean (p = 0.484; ŋp² = 0.042) Heart Rate maximum (p = 0.110; ŋp² = 0.199), Rate Perceived Effort (p = 0.151) or efficiency index (p = 0.480). Therefore, acute caffeine supplementation not effective to increase the performance of soccer players in official matches.
COMMUNICATION | doi:10.20944/preprints202009.0031.v1
Online: 2 September 2020 (06:09:34 CEST)
Each sport has its specific rules, which determine what is allowed (or not) impacting directly on the sport demands. Studies involving physiological and time-motion measurements have shown that soccer is a highly demanding sport. The new coronavirus disease 2019 (COVID-19) has been a world health crisis. Soccer seasons were interrupted worldwide to avoid spreading the virus. Leagues resumed the season (no fans at the arenas) after several weeks of interruption, causing overlay of schedule. This overlay (e.g., games every Sunday and Wednesday) will cause accumulated fatigue on players, raising the risk of injuries. Considering this condensed calendar, the Fédération Internationale de Football Association (FIFA) has changed (temporarily) up to five substitutions during elite games (instead of three as the regular rule allows). Considering the already published scientific evidence, clearly, the change in the soccer substitution rule due to COVID-19 is insufficient. Implementing unlimited substitutions may benefit soccer players' health, coaches’ jobs, more entertainment for fans and sponsors (e.g., keeping intensity during all game, including on the second half) and eventually prolonging the useful life of the players. A real game-changer!
ARTICLE | doi:10.20944/preprints202009.0028.v1
Online: 2 September 2020 (05:27:55 CEST)
The soccer injury rate is distinctly higher during matches than the training sessions. Rules determine how to play, generating specific kinds of fatigue which is associated with the injury incidence. No research has evaluated the impact of potential rule-induced physical demands in soccer or comparing sports. Understanding the differences might be useful for enhancing rules (e.g., safer sport). Therefore, the aims of this study were: a) to described the differences in the rule-induced physical demands of soccer, futsal, basketball, and handball; and b) to evaluate whether soccer rule-induced physical demands are different than the other invasion intermittent team sports, focusing the impact of the substitutions rules. Data were collected from different sports rules (i.e., soccer, futsal, basketball, and handball), and performed hypothetical corrections to equate the other team sports to the soccer (i.e., court dimensions/number of players). The data showed that soccer has higher rule-induced physical demands: lower substitutions, higher dimensions in absolute (eight to 15 times), and relative (four to eight times) values. Hypothetical corrections showed that soccer has remarkably large differences. Therefore, we conclude that soccer has remarkably higher rule-induced physical demands than other team sports, and allowing unlimited substitutions in soccer is a must.
ARTICLE | doi:10.20944/preprints202302.0012.v1
Subject: Social Sciences, Education Studies Keywords: emotional intelligence; mountain sports; life satisfaction; resilience
Online: 1 February 2023 (11:42:54 CET)
High-level performance in mountain sports would be unlikely unless different emotional factors are taken into account through the analysis of psychological characteristics such as mood, resilience or motivation, among many others. In this study, 788 people with a sports degree from the Spanish Federation of Mountain Sports and Climbing (FEDME) participated, 75.3% are men and 24.5% are women. The mean age of the participants was 49.8 years (±12.8), ranging from 18 to 76 years. The Wong Law Emotional Intelligence Scale (WLEIS-S), the RS-14 Resilience Scale and the Satisfaction with Life Scale (SWLS) instrument were used. The aim of this research was to determine the relationship between the dimensions of emotional intelligence, resilience and life satisfaction. The results showed a relationship between several of the dimensions from the instruments used (p<.01). In terms of gender, higher scores were found for women than for men. The regression model shows that both the dimensions of emotional intelligence [Appraisal of own emotions (β=.104; p<.001); Use of emotions (β=.30; p<.001); Emotional Regulation (β=.103; p<.001)] and resilience [Personal competence (β=.402; p<.001)], are predictors of greater life satisfaction, with 44.1% positively explained by the regression model. Further proposals should extend the results obtained with the analysis of more sports modalities and provide evidence that would complement those extracted in this research.
ARTICLE | doi:10.20944/preprints202012.0225.v1
Subject: Life Sciences, Biochemistry Keywords: Repeated Sprint Training; Speed Performance; Physiology; Sports
Online: 9 December 2020 (12:20:00 CET)
Background: Interventions with the performance of sessions with sprints in different intensity manipulations, can be a great alternative to improve physical performance. Objective: To verify the influence of different break times between sprints on the performance of amateur futsal athletes Methods: 10 individuals, men, amateur futsal athletes (Age: 21.5 ± 1.6; Weight: 72.4 ± 6.88; Height: 1.72 ± 0.05; BMI: 24.3 ± 1.2; Fat%: 13.7 ± 3.3, VO2peak: 49.1 ± 10.5) participated in the study. For the intervention, individuals were randomly selected to perform sessions with sprints (10 sets 20 meters) with different pause times, being 15 (S15), 30 (S30) and 60 (S60) seconds. For performance analysis, the speed (km / h) applied to each sprint was used, monitored by a device with a photocell (CEFISE Biotecnologia Esportiva®, Nova Odessa, São Paulo) and the statistical treatment of all data was through the software Statistica 7.0 (Statsoft ™, Tulsa, OK, USA) using a significance level of p≤0.05. Results: There was an interaction between speed and interval time (p = 0.000). For condition S15, a greater reduction in performance was observed (p≤0.05), while for S30 and S60, no significant reduction in performance was observed (p> 0.05). The data for the area under the curve showed a significant difference (p = 0.000), where the interval of 60 seconds (S60) was longer compared to the values of 30 (S30) (p = 0.000) and 15 seconds (S15) (p = 0.000). However, there were no significant differences between the 30 and 15 second data (p = 0.248). Conclusion: Shorter time (15 seconds) of interval between repeated sprints can significantly affect performance when compared to longer breaks (30 and 60 seconds). But, all the conditions tested here, can be positive for the improvement of the performance, mainly in sports that demand fast and efficient motor actions, as for example, futsal.
ARTICLE | doi:10.20944/preprints201801.0105.v1
Subject: Behavioral Sciences, Other Keywords: energy drinks; adolescent lifestyle; alcohol; caffeine; sports
Online: 12 January 2018 (05:12:03 CET)
The European Food Safety Authority (EFSA) has identified some risk factors for the occurrence of side effects linked to energy drinks (EDs) consumption by young people. Tachycardia, sleeplessness, caffeine addiction may be caused by excessive consumption of EDs during parties, sport matches, ect. EDs consumption has been evaluated in a sample of students in Italy together with some aspects of their lifestyle. The survey was performed in two high schools from September 2014 to June 2015. 583 students between 14 to 18 years were recruited and a standard questionnaire (EFSA checklist) was used to collect information on responders characteristics, beverages consumption, EDs with alcohol, and EDs and sports. 350 out of 583 responders (60%) consumed EDs and 146 out of 583 responders (25%) reported an occasional alcohol consumption. Despite 82 out of 146 alcoholic drinkers (56%) were EDs-alcohol consumers, only 70 out of 583 adolescents (12%) reported habitual EDs consumption. Moreover, 38 out of 379 (10%) of all physically active adolescents reported frequent EDs consumption before sportive trainings. Study results highlight the need for primary prevention measures in communication campaigns and training delivered by school to limit potential health threats related to excess of EDs consumption.
ARTICLE | doi:10.20944/preprints202109.0154.v1
Subject: Social Sciences, Education Studies Keywords: sports participation; junior middle school students; prosocial behavior
Online: 8 September 2021 (14:21:00 CEST)
Based on the 2014-2015 China Education Panel Survey (CEPS) and using the propensity score matching method, we studied the causal relationship between physical exercise and prosocial behavior of junior middle school students in China. Ordinary least squares regression and propensity score matching estimation results showed that participation in physical exercise significantly increases students’ prosocial behavior by more than 0.2 standard points. The results of this study were tested and found to be robust.
ARTICLE | doi:10.20944/preprints202104.0211.v1
Subject: Social Sciences, Accounting Keywords: Tourism industry; sports tourism; entrepreneurship; institutional factors; development
Online: 7 April 2021 (15:28:25 CEST)
The aim of this study is to identify the effective institutional factors on the exploitation of entrepreneurial opportunities of the sports tourism industry in developing countries. This research is a qualitative study, the systematic method of Strauss and Corbin (1990) has been used to analyze the data. Interviewing is the main method of collecting data in this research, which semi-structured interviews were done with 45 members of the research community. According to Shane and Venkataraman individual-opportunity nexus framework (2000), interview questions were drafted and simultaneously with data collection from interviews, data analysis was performed. Based on the research results, 75 indicators affecting the exploitation of entrepreneurship opportunities in sports tourism were identified. Our research findings show that the necessary institutional arrangements in regulatory/legal/administrative dimensions (rule of law, government policies), normative/cultural (social norms, values and beliefs), cognitive/educational (promotion of elite knowledge, promotion of social knowledge) and guidance measures/supporter (public sector support, private sector support, complementary attraction and information technology) can improve the rate of entrepreneurial behavior in this area by increasing the ability and willingness of entrepreneurs to take advantage of entrepreneurial opportunities in the field of sports tourism. Finally, according to the research results, it can be suggested that for the growth of the sports tourism industry in developing countries, The existence of a legal, normative, supportive and educational environment will affect the ability and desire of market participants to identify and exploit the entrepreneurial opportunities of this emerging industry.
ARTICLE | doi:10.20944/preprints202102.0464.v1
Subject: Medicine & Pharmacology, Allergology Keywords: anthropometry; height; somatotype; body mass; soccer; sports performance
Online: 22 February 2021 (12:03:33 CET)
The aim of this article was to examine if there are position-specific differences in the morphological characteristics of sub-elite female football players and to establish normative standards for this level of female football players. The morphological features of 101 sub-elite female football players (age: 21.8±2.7 years) were assessed. Twenty anthropometric sites were used in the measurements of body composition and somatotype. The average value of body fat percentage was 20.8±5.7%. The somatotype of the overall group was 4.0–2.4–2.1. Positional significant (p ≤ 0.05) differences were found between goalkeepers and outfield players in morphological characteristics. Goalkeepers were taller, heavier, possessed the highest body fat percentage and showed higher values for all skinfolds, breadth, girth and length measurements. However, there were very few practically worthwhile differences between the outfield positions. Positional groups did not differ (p ≤ 0.05) in somatotype characteristics either. The study suggests that at sub-elite level there are mainly differences between goalkeepers and outfield players, but outfield players are homogeneous when comparing morphological characteristics. These results may serve as normative values for future comparisons regarding the morphological characteristics of female football players.
REVIEW | doi:10.20944/preprints202008.0394.v1
Subject: Medicine & Pharmacology, Sport Sciences & Therapy Keywords: unanticipated; decision-making; brain function; sports; athletes; cognition
Online: 18 August 2020 (16:32:00 CEST)
The performance of choice-reaction tasks during athletic movement has been demonstrated to evoke unfavorable lower limb biomechanics. However, the mechanism of this observation is unknown. We conducted a systematic review examining the association between 1) the biomechanical and functional safety of unplanned sports-related movements (e.g. jumps/runs with spontaneously indicated landing leg/cutting direction) and 2) markers of perceptual-cognitive function (PGF). A literature search in three databases (Pubmed, ScienceDirect, Google Scholar) identified five relevant articles. Study quality, rated by means of a modified Downs & Black checklist, was moderate to high (average: 13.5/16 points). Four of five papers, in at least one parameter, found either an association of lower PGF and reduced task safety or significantly reduced task safety in low vs. high PGF performers. Yet, as a) the outcomes, populations and statistical methods of the included trials were highly heterogeneous and b) only two out of five studies had an adequate control condition (pre-planned movement task), evidence was classified as conflicting. In sum, PGF may represent a factor increasing injury risk during unplanned sports-related movements but future research strengthening the evidence of this association is warranted.
ARTICLE | doi:10.20944/preprints202301.0251.v1
Subject: Medicine & Pharmacology, Sport Sciences & Therapy Keywords: laser beam characterization; laser therapy; medical devices; sports medicine
Online: 13 January 2023 (10:51:11 CET)
Laser therapy devices (LTDs) operating with near-infrared laser light are increasingly being used in sports medicine. For several reasons the users cannot evaluate whether or not such devices emit laser beams according to the specifications provided by the manufacturer and the settings of the device. In this study the laser beams from two different LTDs that can be used in sports medicine were thoroughly characterized by measuring the emitted power, pulse shapes and lengths, and spatial intensity distributions using professional, high-fidelity laser measurement technology. This was repeated for three units of each LDT independently to distinguish problems of individual units from potential intrinsic instrument design errors. The laser beams from the units of one LTD agreed with the settings at the device, with the measured average power for these units being within 3.3% of the set power. In contrast, the laser beams from the units of the other LTD showed large deviations between the settings and the actual emitted light. This device came with three laser diodes that could be used independently and simultaneously. The average power differed greatly between the units as well as between the laser diodes within each unit. Some laser diodes emitted essentially no light, which could lead to a lack of treatment of patients. Other laser diodes emitted much more power than set at the device (up to 230%) that could result in skin irritations or burnings of patients. These findings indicate a need for better standardization and consistency of therapeutic laser light sources.
ARTICLE | doi:10.20944/preprints202212.0346.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: Footwear; Carbon Fiber Insole; Sports Performance; Comfort; Muscle Fatigue
Online: 20 December 2022 (03:15:29 CET)
Carbon fiber insole (CFI), which is lightweight and stiff to reduce energy loss and help wearers perform better in sports, has recently been introduced. However, there are scarce reports on the effects of CFI on sports performance, muscle fatigue and wearing comfort. This study investigat-ed the short-term effects of CFI on sports performance, lower extremity muscle activity, and sub-jective comfort. Thirty young healthy males performed various sports tasks and treadmill runs with wearable sensors under two experimental insole conditions (benchmark insole as a baseline, CFI). The results showed that compared to the benchmark insole, CFI significantly improved sports performance in terms of power generation and agility. However, it activated more of the Tibialis Anterior and Gastrocnemius Medialis muscles and was perceived stiffer, and less com-fortable. These findings suggested that CFI can improve sports performance, but it could cause more lower extremity muscle fatigue and subjective discomfort.
ARTICLE | doi:10.20944/preprints202106.0027.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: athletic program; collegiate sports; UNIVAS; COVID-19; mental management
Online: 1 June 2021 (11:24:42 CEST)
The purpose of this study was to investigate the relationships among student athlete’s identity and mental health during the COVID-19 pandemic. In addition, this study aimed to clarify the relationship between perceived social support from teammates and mental health in student-athletes. Two studies were conducted to investigate to clarify the mental health states of student-athletes in Japan during the COVID-19 pandemic. In Study 1 conducted in April 2020, the participants were 402 male student-athletes, and examined the relationships among student-athlete’s identity and mental health. The results of correlational analyses indicated that there were significant negative correlations between degree of student-athlete’s identity and depression and sports helplessness. In Study 2 conducted in March 2021, the participants were 136 male student-athletes, and examined the relationship between perceived social support from teammates, student-athlete’s identity and mental health. The results indicated that there was significant correlation among social support, student athlete’s identity and mental health. These results suggested that mental health may be improved if student-athletes are strongly aware of their social identity, which is their social role, when unforeseen events such as the COVID-19 pandemic occur. In addition, social support provided by significant others such as teammates may contribute to the improvement of mental health.
ARTICLE | doi:10.20944/preprints202105.0091.v1
Subject: Physical Sciences, Other Keywords: Sports injury, health-seeking behaviour, junior school footballers, Bangladesh
Online: 6 May 2021 (14:52:41 CEST)
Globally, football as a sport has recorded the highest rate of injury morbidity compared with other sports due to the high degree of contact between the players. Coaches play an important role in reducing injuries among the players. The objective of this study was to explore the pattern of football-related sports injuries among junior high school footballers in Dhaka, Bangladesh. A descriptive cross-sectional study was conducted between January 2019 to March 2019 in 20 junior high schools in Dhaka Metropolitan city. We observed 368 boys in the age range of 10 to 18 years old. A pre-structured questionnaire was provided to six trained junior physiotherapists to conduct the face-to-face interview with the boys in the school setting. Most students were from middle-income families. The injury prevalence of defenders was the most (157, 42.7%) followed by mid-fielders (132, 35.94%), forwards (63, 17.1%), and goalkeepers (16, 4.3%). Tackling was the main cause of injury in 21.1% of cases followed by foul play in 19.1% of the cases. In July, there were more injuries (69.0%) and associated muscle strain. Injured footballers did not visit sports physiotherapists as much as they did other health profession and the association was significant. When considering scientific knowledge, students were aware of fitness, flexibility & endurance (25.5%), sports massage (24.5%), the relation of body structure with sports Injury (21.2%), warm-up and/or cool down (19.6%). Based on the study, it was seen that students had no scientific knowledge of sports. As sports is a key activity for school-going children, comprehensive sports injury preventive knowledge is needed for students and sports teachers and coaches. Access to sports physiotherapists is also needed to prevent and manage sports injury at the field level and for rehabilitation.
REVIEW | doi:10.20944/preprints202102.0081.v1
Subject: Social Sciences, Accounting Keywords: Critical speed; exercise prescription; team sports; thresholds; shuttle running
Online: 2 February 2021 (10:05:08 CET)
The overarching purpose of this review was to highlight the utility of different aerobic field tests in terms of the parameters they provide, with a specific focus on shuttle running and all-out testing. Various field tests are discussed in detail and are categorised according to linear continuous running tests (e.g. 12-minute Cooper Test, University of Montreal Track Test [UMTT], 1200/1600 m time trials, 3-minute all-out test for running [3MT]), intermittent shuttle running tests (e.g. yo-yo inter-mittent recovery test level 1 [YYIR1], 30-15 intermittent fitness test [IFT], and the intermittent all-out shuttle test [IAOST]), and continuous shuttle running tests (e.g. 1.2 km shuttle run test [1.2SRT], maximal multi-stage 20-m shuttle test [MSR], 25-m, 30 m and 50-m 3-minute all-out shuttle test [AOST]). Readers will be guided through the theoretical and practical underpinnings of the 3MT methodology, where the all-out testing methodology is stationed within the testing paradigm, and how to practically implement and interpret the results thereof.
ARTICLE | doi:10.20944/preprints202101.0241.v1
Subject: Materials Science, General Materials Science Keywords: hyperelastic materials; FEM; basketball; sports floors; Ogden model; FIBA
Online: 13 January 2021 (11:36:53 CET)
This paper presents a method to determine material constants of a standard basketball shell together with the development of a virtual numerical model of a basketball. Material constants were used as the basis for the hyperelastic material model in the strain energy function (SEF). Material properties were determined experimentally by strength testing in uniaxial tensile tests. Additionally, the digital image correlation technique (DIC) was applied to measure strain in axial planar specimens, thus providing input stress-strain data for the Autodesk software. Analysis of testing results facilitated the construction of a hyperelastic material model. The optimal Ogden material model was selected. Two computer programmes by Autodesk were used to construct the geometry of the virtual basketball model and to conduct simulation experiments. Geometry was designed using Autodesk Inventor Professional 2017, while Autodesk Simulation Mechanical 2017 was applied in simulation experiments. Simulation calculations of the model basketball bounce values were verified according to the FIBA recommendations. These recommendations refer to the conditions and parameters which should be met by an actual basketball. A comparison of experimental testing and digital calculation results provided insight into the application of numerical calculations, designing of structural and material solutions for sports floors.
REVIEW | doi:10.20944/preprints202010.0227.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Intermittent occlusion; Blood flow occlusion; Sports; Ergogenic; Ischemic postconditioning
Online: 12 October 2020 (10:42:36 CEST)
It has been demonstrated that brief cycles of ischemia followed by reperfusion (IR) applied before exercise can improve performance and, IR intervention, applied immediately after exercise (post-exercise ischemic conditioning – PEIC) exerts a potential ergogenic effect to accelerate recovery. Thus, the purpose of this systematic review with meta-analysis was to identify the effects of PEIC on exercise performance, recovery and the responses of associated physiological parameters, such as creatine kinase, perceived recovery and muscle soreness, over 24 h after its application. From 3281 studies, six involving 106 subjects fulfilled the inclusion criteria. Compared to sham (cuff administration with low pressure) and control interventions (no cuff administration), PEIC led to faster performance recovery (p=0.004; ES=-0.49) and lower increase in creatine kinase (p<0.001; ES=-0.71) and muscle soreness (p<0.001; ES=-0.89) over 24 h. The effectiveness of this intervention is more pronounced in subjects with low/moderate fitness level and at least a total time of 10 min of ischemia (e.g. 2 cycles of 5 min) is necessary to promote positive effects.
ARTICLE | doi:10.20944/preprints202208.0437.v1
Subject: Medicine & Pharmacology, Other Keywords: COVID-19; LaLiga; sports; spatial and temporal analysis; serological status
Online: 26 August 2022 (02:59:56 CEST)
Objectives: COVID-19 pandemic interrupted the Spanish professional football competition until May 2020, when it was restarted following a surveillance protocol established by LaLiga. The aims were to describe the infective and serological status of professional football players (PLY) and staff (STF) between May 5th 2020 until April 22nd 2021, to analyze the spatial-temporal distribution of the COVID-19 disease in this cohort and its comparison to the Spanish population. Methods: a prospective observational cohort study was carried out. Differences between PLY and STF were assessed by Chi-squared test and test of equality of proportions. Pearson correlation test was used to measure the presence of an association between the percentages of positivity in population and LaLiga cohort. Results: 137,420 RT-PCR and 20,376 IgG serology tests were performed in 7,112 professionals. Positive baseline serology was detected in 10.57% of PLY and 6.38% of STF. Among those who started the follow-up as not infected and before STF vaccination, 11.87% of PLY and 5.03% of STF became positive. Before summer 2020 the prevalence of infection was similar than the observed at national level. The percentage of positivity in the Spanish population was higher than in LaLiga cohort, but both series showed a similar decreasing trend.
ARTICLE | doi:10.20944/preprints202107.0378.v1
Subject: Earth Sciences, Atmospheric Science Keywords: water quality; outdoor sports; dissolved oxygen; stagnant water; cable ski
Online: 16 July 2021 (14:36:47 CEST)
Abstract: The concept of sustainability applied to sports activities means ensuring that the economic benefits brought about by their development are not obtained at the expense of causing ecological damage or interference in local cultural habits. A cable-ski is a nautical ski system whereby a motorboat is substituted by a cable traction system powered by an electric motor. The effect on the quality of the water in those places that can boast cable-ski facilities has been described in cold freshwater lakes. Objective: Our purpose was to study the evolution of water quality in a ten-year period after the installation of a cable-ski facility in a warm, salted, semi-stagnant pond. Material and Method: Review of the data gathered from the routine test carried out by the Laboratory of the Council of Alcúdia from 2010 to 2019 Results: The levels of dissolved oxygen have increased, being significantly higher in the period 2016 – 2019 than in that of 2010 – 2015. The turbidity of the water has also seen a reduction in the second period with respect to the first. Conclusion: It seems that cable-ski improves the quality of water even warm, high-conductivity, semi-stagnant conditions
REVIEW | doi:10.20944/preprints202009.0139.v1
Subject: Behavioral Sciences, Cognitive & Experimental Psychology Keywords: Cognitive load theory; dynamic visualizations; design techniques; learning; team sports
Online: 5 September 2020 (10:41:11 CEST)
Dynamic visualizations have been developed to exchange information that transforms over time across a broad range of professional and academic contexts. However, these visual tools may impose substantial demands on the learner’s cognitive resources that are very limited in current knowledge. Cognitive load theory has been used to improve learning from dynamic visualizations by providing certain design techniques to manage learner cognitive load without adding any oral/written explanations. This systematic review examined a series of experimental studies assessing the roles of these design techniques in learning tactical scenes of play through dynamic visualizations. Electronic databases PubMed and Google Scholar were used to search relevant articles. Eleven studies were eventually included for the systematic review based on the eligibility criteria. The present review revealed that adapting design techniques to the level of learners’ expertise, type of depicted knowledge, and level of content complexity is a crucial part of effective learning.
ARTICLE | doi:10.20944/preprints201811.0103.v1
Subject: Medicine & Pharmacology, Sport Sciences & Therapy Keywords: acute physical stress; sports performance; heart rate variability; physical exhaustion
Online: 5 November 2018 (10:35:01 CET)
Athletes are exposed to high-intensity loads to promote athletic performance, however without appropriate evaluation for its effects. This study investigates the effects of four types of exhaustion exercises on Heart Rate Variability (HRV) and Poincaré features as markers of central fatigue; Creatine Kinase (CK) and blood lactate concentrations ([LA-]b) as biomarkers of peripheral fatigue. To achieve this purpose, ten healthy volunteers were exposed to exhaustive exercise using isotonic-, isometric-, aerobic-, and anaerobic-fatigue protocols. HRV Poincaré features, standard deviation of instantaneous beat-to-beat R-R interval variability (SD1) and standard deviation of continuous long-term R-R interval variability (SD2) variables were collected. Central fatigue was tested through the sympathetic stress index (SS) and the sympathetic and parasympathetic index (SS/SD1). Blood samples were collected at the beginning and at the end of the exercises to determine CK and [LA-]b. The SD1 decreased in each exercise protocol, while the SS and SS/SD1 increased. [LA-]b and CK increased at the end of each protocol and correlated with SD1 and SS/SD1. HRV, CK, and [LA-]b are acute markers to detect, both central and peripheral fatigue; sensitive to the type, duration, and intensity of exercise, being HRV a novel noninvasive marker, simple and useful for sports coaches and athletes.
REVIEW | doi:10.20944/preprints201808.0503.v1
Subject: Life Sciences, Immunology Keywords: HMB; Branched-chain amino acid; Strength training; Sports nutrition; Inflammation.
Online: 29 August 2018 (14:12:18 CEST)
β-hydroxy β-methylbutyrate (HMB) is a bioactive metabolite formed from breakdown of the branched-chain amino acid leucine. Given the popularity of HMB supplements among different athletes, specifically, those who engage in regular resistance training, this review was performed to summarize current literature on some aspects of HMB supplementation that have received less attention. Because of the small number of published studies, it has not been possible to conclude the exact effects of HMB on cardiovascular parameters, oxidative stress and inflammatory markers. Thus, the interpretation of outcomes should be taken cautiously. However, the data presented here suggest that acute HMB supplementation may attenuate pro-inflammatory response following an intense resistance exercise in athletes. Also, the available findings collectively indicate that chronic HMB consumption in conjunction with resistance training has no more adaptive advantages associated with decreasing cardiovascular risk factors and oxidative stress markers. Taken together, there is clearly a need for further well-designed, longer duration studies to support these findings and determine whether HMB supplementation affects the adaptations induced by resistance training associated with body’s inflammatory condition, antioxidative defense system, and cardiovascular risk factors in humans.
ARTICLE | doi:10.20944/preprints201805.0008.v1
Subject: Social Sciences, Sociology Keywords: JCQ; job crafting; construct validity; leisure sports instructor; valid scale
Online: 1 May 2018 (11:36:48 CEST)
In previous researches, Job Crafting questionnaire to develop is consists of 3 factors which are Task Crafting, Cognitive Crafting, and Relationship Crafting with 12 to 17 items. The purpose of study is to develop JCQ for leisure sports instructor of Korean. 274 valid samples are used for analysis. Data collecting is purposeful sampling. At result, for Korean Sports Instructor Job Crafting Scale is constructed 3 factors with 12 items is constructed by 3 step procedure. KSIJCQ is confirmed on convergent discriminant validity evidence. In conclusion, KSIJCQ is a valid scale of the measuring and distributes Job Crafting of generalization in sports.
ARTICLE | doi:10.20944/preprints201609.0103.v1
Subject: Mathematics & Computer Science, Computational Mathematics Keywords: Maximum entropy model; K-means clustering; accuracy; classification; sports forecasting
Online: 27 September 2016 (11:10:50 CEST)
Predicting the outcome of a future game between two National Basketball Association (NBA) teams poses a challenging problem of interest to statistical scientists as well as the general public. In this article, we formalize the problem of predicting the game results as a classification problem and apply the principle of maximum entropy to construct NBA maximum entropy (NBAME) model that fits to discrete statistics for NBA games, and then predict the outcomes of NBA playoffs by the NBAME model. The best NBAME model is able to correctly predict the winning team 74.4 percent of the time as compared to some other machine learning algorithms which is correct 69.3 percent of the time.
ARTICLE | doi:10.20944/preprints202208.0549.v1
Subject: Medicine & Pharmacology, Sport Sciences & Therapy Keywords: Yoga of Immortals (YOI); atheltic performance; Dewan Sport Inventory; Sports resilience
Online: 31 August 2022 (14:33:54 CEST)
The mental and emotional health of an athlete is crucial for their performance and well-being. Sports-related stress can significantly impair that mental health. Yoga of Immortals (YOI) is a unique combination of specific yogic postures, breathing exercises, sound therapy & meditation, which has demonstrated benefit in improving measures of mental health. This study used the Sports Mind Inventory (SMI) to examine whether YOI can improve the resilience of athletes to sports-related stress. Participants were a diverse set of athletes based in Mauritius who routinely engage in a wide range of athletic activities. Participants were randomly assigned to receive four weeks of YOI or no intervention. Both groups completed the SMI questionarie at baseline and again after four weeks. The YOI intervention significantly increased the total mean SMI scores by 14%, indicating improved sports resilience and psychological health. No improvement was observed in the control group. This study demonstrates that YOI is a promising intervention in improving sports related stress.
ARTICLE | doi:10.20944/preprints202107.0034.v1
Subject: Life Sciences, Biochemistry Keywords: Gene doping; Gene therapy; Erythropoietin; Adenoviral vector; Sports; Athlete; RNA sequencing
Online: 1 July 2021 (14:30:04 CEST)
The World Anti-Doping Agency (WADA) has prohibited gene doping in the context of progress in gene therapy. In addition, there is a risk of the EPO gene being applied in gene doping among athletes. Along with this, development of a gene-doping test has been underway in worldwide. Here, we had two purposes: to develop a robust gene doping mouse model using the human EPO gene (hEPO) transferred using recombinant adenovirus (rAdV) as a vector and to develop a detection method to prove gene doping using this model. The rAdV including the hEPO gene were injected intravenously to transfer the gene to the liver. After injection, the mice developed significantly increased red blood cell counts in whole blood and increased gene expressions of hematopoietic markers in the spleen, indicating successful development of the gene doping model. Next, we detected direct and indirect proof of gene doping in whole blood DNA and RNA using qPCR assay and RNA sequencing. Proof was detected in one drop of whole blood DNA and RNA over a long period; furthermore, the overall RNA expression profiles significantly changed. Therefore, we have advanced detection of hEPO gene doping in humans.
ARTICLE | doi:10.20944/preprints202010.0079.v1
Subject: Life Sciences, Biochemistry Keywords: Stretch-shortening cycle; Peak power; Plyometric with load; Team sports; Throwing.
Online: 5 October 2020 (12:11:13 CEST)
This study examined the effects of incorporating 8 weeks of biweekly upper limb loaded plyometric training (elastic band) into the in-season regimen of handball players. Trial participants were assigned between control (n = 15, age: 18.1±0.5 years, body mass: 73.7±13.9 kg) and experimental (n = 14, age: 17.7±0.3 years, body mass: 76.8±10.7 kg) groups. Measures obtained pre- and post- included a cycle ergometer force-velocity test, ball throwing velocity in three types throw, 1-RM bench press and pull-over, and anthropometric estimates of upper limb muscle volumes. Gains in the experimental group relative to controls included absolute muscle power (W) (Δ23.3%; t-test p<0.01; d=0.083), relative muscle power (W.kg-1) (Δ22.3%; t-test p<0.01; d=0.091), and all 3 types of ball throw (Δ18.6%, t-test p<0.01, d=0.097 on jumping shot; Δ18.6%, t-test p<0.01; d=0.101 on 3-step running throw; and Δ19.1%, t-test p<0.01, d=0.072 on standing throw). Furthermore, a significant improvement by time interactions was observed in both groups on 1-RM bench press and pull-over performance. However, upper limb muscle volumes remained unchanged in both groups. We conclude that adding biweekly elastic band plyometric training to standard training improves measures important to game performance. Accordingly, such exercises can usefully be adopted as a part of handball training.
ARTICLE | doi:10.20944/preprints202006.0291.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: food exchange list; sports foods; dietary supplements; dietetic practice; menu planning
Online: 24 June 2020 (09:41:43 CEST)
Food exchange lists have been widely used in dietary practice in health and disease situations, but there are still no exchange lists for sports foods. The aim of this study was to develop a sports foods exchange list based on previously published statistical criteria. A cross-sectional study of the nutritional composition of sports foods, regarding macronutrients and energy, was carried out. A total of 323 sports foods from 18 companies were selected and divided into seven groups: sports drinks; sports gels; sports bars; sports confectionery; protein powders; protein bars; and liquid meals. A sports foods composition database based on portion size was created. Food exchange groups, with the definition of the amounts - in grams - of each sports foods within each group, were designed using the same methodology and statistical criteria as previously published. The nutritional composition of the portions usually consumed by athletes and/or recommended in commercial packaging was used to calculate the mean energy and macronutrient values for each group. Within each sports foods group, different subgroups were defined due to differences in the main and/or secondary macronutrient. The mean nutrient values of each exchange group and the subgroups were determined according to previously established rounding criteria. This sports foods exchange list, made up of commercial sports products, is a novel tool for dietetic practice. Its management will allow dietitians to adapt dietary plans more precisely to the training and/or competition of the athlete.
ARTICLE | doi:10.20944/preprints201912.0015.v1
Subject: Social Sciences, Other Keywords: school sports facility; assessment; t-sne; fuzzy c mean; unsupervised learning
Online: 3 December 2019 (05:24:26 CET)
The aim of this study is (a) to develop, test, and employ a combined method of unsupervised machine learning to objectively assess the condition of sports facility in primary schools (PSSFC) and (b) examine the examine the geographical and typological association with PSSFC. Based on the Sixth National Sports Facility Census (NSFC), six PSSFC indicators (indoor and outdoor facility included) were selected as the measurements and decomposed by using the t-stochastic neighbor embedding (t-SNE). Thereafter, the Fuzzy C-mean (FCM) algorithm was used to cluster the same type of PSSFC with selecting the optimum numbers of evaluation level. Overall 845 primary schools in Shanghai, China were recruited and tested by this combined approach of unsupervised machine learning. In addition, the two-way analysis of covariance was used to examine the location and types of school associated with PSSFC variables in each level. The combined method was found to have acceptable reliability and good interpretability, differentiating PSSFC into five gradient levels. The characteristics of PSSFC differ by the location and school type of individual school. Our findings are conducive to the regionalized and personalized intervention and promotion on the children’s physical activity (PA) upon the practical situation of particular schools.
ARTICLE | doi:10.20944/preprints201809.0357.v1
Subject: Life Sciences, Other Keywords: Performance, Sports, Aortic Valve, Sinus of Valsalva, Echocardiography, Sudden cardiac death
Online: 18 September 2018 (14:40:43 CEST)
Aortic rupture is known as one of the potential causes of sudden cardiac death in athletes. Nevertheless, adaptation strategies for aortic root dilation in athletes vary. The purpose of this study was to investigate aortic root adaptation to physical workload and to determine if aortic root’s and left ventricle sizes are contingent upon the physical workload. Echocardiography was applied to 151 subjects to measure the aortic root at aortic valve annulus (AA) and at sinus of Valsalva (VS). 122 were athletes (41 females and 81 males) and 29 were non-athletes (14 females and 15 males). Of the 41 female athletes, 32 were endurance athletes, and 9 strength athletes. From 81 male athletes, 56 were endurance athletes, and 25 were strength athletes. AA and VS mean values for the body surface area were presented as rAA and rVS. Left ventricle (LV) meaures incuded LV end-diastolic diameter (LVEDD), interventricular septum thickness in diastole (IVSTd), LV posterior wall thickness in diastole (LVPWTd), LV mass (LVM), LV mass index, LV end-diastolic diameter index (LVEDDI). Results indicated that VS was higher in female athletes (28.9±2.36mm) than in non-athletes (27.19±2.87mm, p=0.03). On the other hand, rAA was higher in strength athletes (12.19±1.48mm/m2) than in endurance athletes (11.12±0.99mm/m2, p=0.04). Additionally, rVS and rAA were higher in female strength athletes (17.19±1.78mm/m2, 12.19±1.48mm/m2) than female basketball players (15.49±1.08mm/m2, p=0.03, 10.75±1.06 mm/m2, p=0.02). Statistically significant positive moderate correlations were found between VS and LVEDD, LVM, IVSTd, LVPWTd, rVS and LVEDDI parameters in all athletes. The diameter of Valsalva sinus was greater in female athletes compared to non-athletes. The rAA mean value for body surface area was greater in female athletes practising strength sports as compared to their counterparts who were practising endurance sports. The diameter of the aortic root at sinuses positively correlated with the LV size in all athletes. Trial was registered at ClinicalTrials.gov Identifier: NCT03656861, September 3, 2018 (retrospectively registered).
ARTICLE | doi:10.20944/preprints201611.0017.v1
Subject: Mathematics & Computer Science, Artificial Intelligence & Robotics Keywords: machine learning; unbalanced data; predicting rare events; NFL football; sports analytics
Online: 2 November 2016 (07:07:06 CET)
Turnovers in the National Football League (NFL) occur whenever a team loses possession of the ball due to a fumble, or an interception. Turnovers disrupt momentum of the offensive team, and represent lost opportunities to advance downfield and score. Teams with a positive differential turnover margin in a given game win $70\%$ of the time. Turnovers are statistically rare events, occurring apparently randomly. These characteristics make them difficult to predict. This investigation advances the hypothesis that turnovers are predictable in NFL football. Machine learning models are developed to learn the concept: At any point within a football game, what is the likelihood that a turnover will be observed on the next play from scrimmage? Results presented suggest evidence to support the working hypothesis. Under certain conditions, both fumbles and interceptions can be anticipated at low false discovery rates (less than $15\%$). This approach may be useful to inform in-game strategies to mitigate the negative consequences of turnovers by an offensive team, or to maximize their probability by a defensive squad.
ARTICLE | doi:10.20944/preprints202206.0087.v2
Subject: Social Sciences, Sociology Keywords: public sports service; new urbanization; development dynamic relationship; interaction mechanism; optimal path
Online: 8 June 2022 (10:19:08 CEST)
In the new period, the state has made every effort to promote the new urbanization of public sports service. Entropy method, coupled coordination model, cold hot spot analysis is used to explore the dynamic relationship between public sports services and the development of new urbanization in China from 2008 to 2017. The results show that: (1) The development of the internal subsystem of public sports service is not balanced, the sports financial investment system grows rapidly, but the development of professional sports talent team is slow. (2) The imbalance of regional development cannot be ignored, and the public sports service level shows a decreasing gradient from east to west. (3) The regional development features are different. The eastern region is dominated by the coordinated development of sports public service and urbanization, while the central region is mainly in the type of public sports service lag, while the western region has multiple complex characteristics of low-level coordination and public sports service lag. Therefore, it is proposed that the construction of modern public sports service system should be investigated in the context of the development of new urbanization. It should be promoted from the following aspects: promoting the extension of public sports service to rural areas, engendering the "citizen's right" of sports health to the migrant population, conforming to the trend of mass sports intelligence, developing green sports and revitalizing idle sports assets in cities.
REVIEW | doi:10.20944/preprints202012.0559.v1
Subject: Medicine & Pharmacology, Allergology Keywords: sports cardiology; athlete; caffeine; anabolic steroids; heart disease; cardiac magnetic resonance imaging
Online: 22 December 2020 (12:39:52 CET)
Several performance-enhancing or ergogenic drugs have been linked to both significant adverse cardiovascular effects and increased cardiovascular risk. Even with increased scrutiny on the governance of performance-enhancing drugs (PEDs) in professional sport and heightened awareness of the associated cardiovascular risk, there are some who are prepared to risk their use to gain competitive advantage. Caffeine is the most commonly consumed drug in the world and its ergogenic properties have been reported for decades. Thus, the removal of caffeine from the World Anti-Doping Agency (WADA) list of banned substances, in 2004, has naturally led to an exponential rise in its use amongst athletes. The response to caffeine is complex and influenced by both genetic and environmental factors. Whilst the evidence may be equivocal, the ability of an athlete to train longer or at a greater power output cannot be overlooked. Furthermore, its impact on the myocardium remains unanswered. In contrast, anabolic steroids are recognised PEDs that improve athletic performance, increase muscle growth and suppress fatigue. Their use, however, comes at a cost, afflicting the individual with several side effects, including those that are detrimental to the cardiovascular system. This review addresses the effects of the two commonest PEDs, one legal, the other prohibited, and their respective effects on the heart, as well as the long-term implications.
ARTICLE | doi:10.20944/preprints201911.0267.v1
Subject: Behavioral Sciences, Other Keywords: psychological wellbeing; gifted teenagers; giftedness in math; giftedness in humanities; giftedness in sports
Online: 24 November 2019 (04:47:02 CET)
Current article presents the study of psychological wellbeing of adolescents (n=168, age 15-17) gifted in math, humanities and sports and educated in advanced programs for gifted children. Theoretical framework of this study is eudemonic concept of psychological wellbeing by C. Ryff. Psychological wellbeing is measured with Ryff wellbeing scales in Russian adaptation by L.V. Zhukovskaya and E.G. Troshikhina. The study is aimed at understanding differences in psychological wellbeing of gifted teenagers connected to gender and type of giftedness. The results suggest that general wellbeing score did not differ for adolescents with different types of giftedness or of different genders. Separate components of psychological wellbeing, such as purpose in life and self-acceptance, are influenced by activity connected to the talent. Gender differences are subjected to age-specific trends of personal development in adolescence. Type of giftedness might reinforce these trends.
ARTICLE | doi:10.20944/preprints202102.0044.v1
Subject: Medicine & Pharmacology, Sport Sciences & Therapy Keywords: women's health; sports; non-communicable disease; obesity; physical activity; health promotion; mixed-methods; Africa
Online: 1 February 2021 (14:23:47 CET)
Despite the well-documented health benefits of recreational sports, few opportunities exist in lower- and middle-income countries for adult women to participate in recreational physical activities. An explanatory sequential mixed methods approach was used to explore associations between an innovative soccer program for adult women and self-reported health status. Cross-sectional survey data were collected in 2018-2019 from 702 women in the Nikumbuke Project, a health and literacy program in southeastern rural Kenya, followed by focus group discussions with 225 women who also participated in the Project's soccer program. Quantitative findings suggest that women who participated in soccer had 67% greater odds of reporting good or excellent health than their non-soccer playing peers. Thematic analysis of qualitative data indicated that women credited soccer with less pain, fatigue, and stress, as well as weight loss and reduced dependence on medicine for hypertension, pain, and sleep problems. Women equated health benefits with greater ease and efficiency in completing chores, reduced worries, youthful energy, male-like strength, and pleased husbands. Soccer programs for adult women may be particularly effective interventions in settings where access to health care is limited and where lack of opportunity to engage in physical aerobic activity increases women's risks for poor health outcomes. .
ARTICLE | doi:10.20944/preprints202208.0512.v1
Subject: Engineering, Mechanical Engineering Keywords: Contact Mechanics; Cross-Country Skiing; Cross-Country Ski; Load Conditions; Ski-Camber Profile; Sports Equipment
Online: 31 August 2022 (02:26:22 CEST)
In cross-country skiing the time difference between a race winner and the person coming second is typically very small. Since much of the energy is spent on overcoming resistive forces, a relatively small reduction of these can have a significant impact on the results. The resistive forces come partly from the friction in the tribological interface, between the ski and the snow, and as with many tribological applications the characterisation of its origin, plays an important role in determining the frictional properties. Also in cross-country ski friction, there are several scales impacting the frictional performance, with the major contributors being the ski-camber profile and ski-base structure. Macro-scale measurements of the ski's camber profile under load, are often used to determine how adequate the ski is for a specific condition. The characteristic properties usually obtained are, the force required to collapse the ski to a certain camber height, the topography of the kick-wax zone, and by simple means a determined lengths of the frictional interface, i.e., the apparent contact length. To this date, there are some mathematical models, but there is no robust way of determining the macro-scale contact properties between a cross-country ski and a counter surface using simulations. In the present paper an Artificial neural networks (ANN) is trained to predict the ski-camber profile for various loads placed at different positions, and a well established deterministic approach is used to simulate the contact between the ANN-predicted ski-camber profile and a linearly elastic body with a flat surface, representing the snow. The results suggest that this method is feasible for the determination of the apparent contact characteristics of different skis. Moreover, we show that the apparent contact area does not linearly depend on the load, and that the elastic properties of the counter surface also has a large impact on the apparent contact area and the average apparent contact pressure.
REVIEW | doi:10.20944/preprints201710.0081.v1
Subject: Life Sciences, Other Keywords: dietary assessment; food record; FFQ; biomarker; doubly labeled water; energy intake; validity; athletes; sports nutrition
Online: 12 October 2017 (09:43:35 CEST)
Dietary assessment methods recognized as appropriate for the general population are usually applied in a similar manner to athletes, despite knowledge that sport-specific factors can complicate assessment and impact accuracy in unique ways. As dietary assessment methods are used extensively within the field of sports nutrition, there is concern the validity of methodologies have not undergone more rigorous evaluation in this unique population sub-group. The purpose was to systematically review studies comparing two or more methods of dietary assessment, including dietary intake measured against biomarkers or reference measures of energy expenditure, in athletes. Six electronic databases were searched for English-language, full-text articles published from January 1980 until June 2016. The search strategy combined the following keywords: diet, nutrition assessment, athlete and validity; where the following outcomes are reported but not limited to: energy intake, macro and/or micronutrient intake, food intake, nutritional adequacy, diet quality, or nutritional status. Meta-analysis was performed on studies with sufficient methodological similarity, with between-group standardized mean differences (or effect size) and 95 % confidence intervals (CI) calculated. Of the 1624 studies identified, 18 were eligible for inclusion. Studies comparing self-reported energy intake (EI) to energy expenditure assessed via doubly labelled water were grouped for comparison (n=11) and demonstrated mean EI was under-estimated by 19 % (- 2793 ± 1134 kJ/d). Meta-analysis revealed a large pooled effect size of - 1.006 (95% CI: -1.3 to -0.7; p<0.001). The remaining studies (n=7) compared a new dietary tool or instrument to a reference method(s) (e.g. food record, 24-h dietary recall, biomarker) as part of a validation study. This systematic review revealed there are limited robust studies evaluating dietary assessment methods in athletes. Existing literature demonstrates substantial variability between methods, with under and misreporting of intake frequently observed. There is a clear need for careful validation of dietary assessment methods, including emerging technical innovations, among athlete populations.
ARTICLE | doi:10.20944/preprints202010.0436.v1
Subject: Keywords: Naïve Bayes Classification; Eulers Strength Formula; Cricket Prediction; Supervised Learning; KNIME Tool; Cricket prediction; sports analytics; multivariate regression; neural network
Online: 21 October 2020 (12:34:00 CEST)
In cricket, particularly the twenty20 format is most watched and loved by the people, where no one can guess who will win the match until the last ball of the last over. In India, The Indian Premier League (IPL) started in 2008 and now it is the most popular T20 league in the world. So we decided to develop a machine learning model for predicting the outcome of its matches. Winning in a Cricket Match depends on many key factors like a home ground advantage, past performances on that ground, records at the same venue, the overall experience of the players, record with a particular opposition, and the overall current form of the team and also the individual player. This paper briefs about the key factors that affect the result of the cricket match and the regression model that best fits this data and gives the best predictions. Cricket, the mainstream and widely played sport across India which has the most noteworthy fan base. Indian Premier League follows 20-20 format which is very unpredictable. IPL match predictor is a ML based prediction approach where the data sets and previous stats are trained in all dimensions covering all important factors such as: Toss, Home Ground, Captains, Favorite Players, Opposition Battle, Previous Stats etc, with each factor having different strength with the help of KNIME Tool and with the added intelligence of Naive Bayes network and Eulers strength calculation formula.