Football is one of the most-watched sports,but analyzing players’per-formance is currently difficult and labor intensive.Performance analysis is done manually,which means that someone must watch video recordings and ...Football is one of the most-watched sports,but analyzing players’per-formance is currently difficult and labor intensive.Performance analysis is done manually,which means that someone must watch video recordings and then log each player’s performance.This includes the number of passes and shots taken by each player,the location of the action,and whether or not the play had a successful outcome.Due to the time-consuming nature of manual analyses,interest in automatic analysis tools is high despite the many interdependent phases involved,such as pitch segmentation,player and ball detection,assigning players to their teams,identifying individual players,activity recognition,etc.This paper proposes a system for developing an automatic video analysis tool for sports.The proposed system is the first to integrate multiple phases,such as segmenting the field,detecting the players and the ball,assigning players to their teams,and iden-tifying players’jersey numbers.In team assignment,this research employed unsu-pervised learning based on convolutional autoencoders(CAEs)to learn discriminative latent representations and minimize the latent embedding distance between the players on the same team while simultaneously maximizing the dis-tance between those on opposing teams.This paper also created a highly accurate approach for the real-time detection of the ball.Furthermore,it also addressed the lack of jersey number datasets by creating a new dataset with more than 6,500 images for numbers ranging from 0 to 99.Since achieving a high perfor-mance in deep learning requires a large training set,and the collected dataset was not enough,this research utilized transfer learning(TL)to first pretrain the jersey number detection model on another large dataset and then fine-tune it on the target dataset to increase the accuracy.To test the proposed system,this paper presents a comprehensive evaluation of its individual stages as well as of the sys-tem as a whole.展开更多
Based on the “Healthy China 2030 Planning Outline”, the literature method and logical analysis method are used to review and analyze the implementation process of China’s school football policy from three dimension...Based on the “Healthy China 2030 Planning Outline”, the literature method and logical analysis method are used to review and analyze the implementation process of China’s school football policy from three dimensions: value, interest appeal and institutional background. The study believes that in order to break through the bottleneck of policy implementation and improve the effect of policy implementation, it is necessary to establish correct values and form broad recognition of policies;meet the reasonable interests of all parties and form a synergy for policy implementation;optimize the institutional environment for policy implementation and form effective incentives.展开更多
Football is the most popular sport worldwide and is associated with a high injury rate, most of which are the result of trauma from player contact. Ankle injuries are among the most commonly diagnosed injuries in the ...Football is the most popular sport worldwide and is associated with a high injury rate, most of which are the result of trauma from player contact. Ankle injuries are among the most commonly diagnosed injuries in the game. The result is reduced physical activity and endurance levels, lost game time, and considerable medical cost. Sports medicine professionals must employ the correct diagnostic tools and effective treatments and rehabilitation protocols to minimize the impact of these injuries on the player. This review examines the diagnosis, treatment, and postoperative rehabilitation for common football injuries of the ankle based on the clinical evidence provided in the current literature.展开更多
BACKGROUND Flexibility,agility and muscle strength are key factors to either win or lose a game.Recently the effect of a new technique,deep transverse friction massage(DTFM)on muscle extensibility as compared to tradi...BACKGROUND Flexibility,agility and muscle strength are key factors to either win or lose a game.Recently the effect of a new technique,deep transverse friction massage(DTFM)on muscle extensibility as compared to traditional stretching techniques has been examined.AIM To compare the effect of DTFM vs static and dynamic stretching techniques on the hamstring’s extensibility,agility,and strength amongst Lebanese and Syrian football players.Recording the incidence of non-contact hamstring muscle injury was a secondary objective.METHODS This study is a single-blinded prospective longitudinal randomized controlled trial.The experiment took place over a period of four weeks.Football players were randomized into three intervention groups(static stretching;dynamic stretching;DTFM).Participants of each group were followed-up carefully by assessors during their intervention sessions three times per week,for a total of 12 sessions and during the data collection.Extensibility,agility,and strength were compared between intervention groups at(baseline;acute;and chronic)phases.Straight leg raise and 1 repetition maximum tests were used to measure the dominant leg hamstring muscle extensibility and maximal strength respectively.T-drill test was used to assess the lower extremities agility.RESULTS Of 103 Lebanese and Syrian male football players aged between 18 and 35 were sampled from Damascus-Syria and South of Lebanon to participate in this study.Between-groups measures of acute strength(P=0.011)and chronic extensibility(P=0.000)solely showed a significant difference,and the static group showed to be superior as compared to the other groups.No loss to follow-up or protocol violation was recorded.CONCLUSION Static stretching is showing to be superior to the other techniques used,regarding gaining long-term extensibility and short-term maximal muscle strength.In addition,DTFM showed improvements but did not outweigh the effects on footballers’performance when comparing it to static and dynamic techniques.Finally,no difference between the interventions is recorded regarding the rate of muscle injuries incidence.展开更多
In this paper, we utilize Data Envelopment Analysis (DEA), which is a linear programming-based technique, for evaluating the performance of the teams which operate in the Iranian primer football league. We use Analyti...In this paper, we utilize Data Envelopment Analysis (DEA), which is a linear programming-based technique, for evaluating the performance of the teams which operate in the Iranian primer football league. We use Analytical Hierarchy Process (AHP) technique for aggregating the sub-factors which involve in input-output factors, and then DEA is used for calculating the efficiency measures. Also, AHP is used to construct some weight restrictions for increasing the discrimination power of the used DEA model. For calculating the efficiency measures, input-oriented weight-restricted BCC model is utilized.展开更多
Background: A cardiovascular assessment is rarely performed among athletes despite more and more frequently reported fatal events. Most of these accidents are of cardiovascular origin. Moreover, data on ECG or Echocar...Background: A cardiovascular assessment is rarely performed among athletes despite more and more frequently reported fatal events. Most of these accidents are of cardiovascular origin. Moreover, data on ECG or Echocardiography are rare in our context justifying our study to assess electrical and echocardiographic pattern among high-level footballer in Bamako. Methods: It was a cross-sectional study conducted in Bamako from April 2015 to?March 2016 among high-level footballers aged 14 to 35 years old without distinction of sex with at least 10 hours weekly training since one year. The ECG and echocardiographies were recorded respectively with a 12-lead CONTEC and an ATL 5000 echocardiographic machine. Each ECG record was analyzed by a cardiologist in accordance with the Seattle 2013 criteria and those pathological reviewed by a second cardiologist according to the same criteria and definitively classified as normal (physiological) or abnormal ECG (requiring complementary explorations). A third cardiologist was associated in case of discordance of the first results. The collected data were inserted in a Microsoft Excel sheet and analyzed with SPSS version 20. Chi Square and Fisher statistical tests were used to compare our results. The significance level was set at 0.05. Results: We collected data of 227 top footballers with male sex represented in 90.3% giving a sex ratio of 3.04. Means for age, weight, height, body mass index (BMI) were respectively 22 years, 69.90 kg, 177.21 cm and 22.21 kg/m2. Sinus bradycardia was found in a proportion of 45.8% more represented in the age group of 30 and more years (p = 0.275). First-degree atrioventricular block (AVB) was present in 19.4%. Short PR was found in 0.4% of the sample. Left ventricular hypertrophy (LVG) according to the Sokolow index was found in 70.5% (96.9% males and 3.1% females) with p Conclusion: Many electrical and echocardiographic signs of cardiac adaptation were found in our sample and must lead to a closer follow-up of these trained footballers to avoid or prevent dramatic cardiovascular events.展开更多
Context and Objective: Hamstring strain is a common injury in football and it causes a significant amount of time lost from competition and training. Since poor flexibility is thought to predispose to muscle strain, s...Context and Objective: Hamstring strain is a common injury in football and it causes a significant amount of time lost from competition and training. Since poor flexibility is thought to predispose to muscle strain, stretching is routinely recommended during warm-up routines by coaches to prevent injuries. However, available evidence suggests that pre-exercise stretching (PES), especially static stretching, has no benefit on injury rates and may even reduce performance in explosive type activities. We designed this study to assess the attitudes, beliefs and practices of football coaches regarding stretching in the prevention of hamstring strains. Design: A cross-sectional survey. Setting: Mauritius Football Association (MFA). Participants: 26 football coaches registered with the MFA. Intervention: Questionnaires were distributed to football coaches of the MFA via sports officers. Questionnaires were then collected two weeks after distribution. Main Outcome Measures: Attitudes, beliefs and practices of football coaches regarding stretching in the prevention of ham-string strains. Results: MFA coaches held generally positive attitudes and beliefs towards stretching. 88% of coaches felt that PES is beneficial and 93% believed that PES prevents hamstring strains. The majority of coaches recommended stretching after warming up (81%) and after the training session (93%). 76% of coaches also advised stretching outside the training sessions. 96% of coaches used static stretching to stretch the hamstrings. The hamstrings were stretched on average for 4 times at each training session and the mean duration of a static stretch was 12 seconds. Conclusions: Nearly all coaches believed that PES prevents hamstring strains although evidence is limited. Some of the coaches’ beliefs and practices were not in line with current recommendations. Coaches reported that their stretching practices would be most likely influenced by scientific research. Thus there is an urgent need to devise awareness and training programmes in this area.展开更多
BACKGROUND Anterior cruciate ligament(ACL)injuries represent detrimental injuries in the National Football League(NFL).A significant portion of these injuries often occur in preseason exhibitions.The Coronavirus disea...BACKGROUND Anterior cruciate ligament(ACL)injuries represent detrimental injuries in the National Football League(NFL).A significant portion of these injuries often occur in preseason exhibitions.The Coronavirus disease 2019 pandemic presented a unique disruption to preseason NFL football with the cancelation of all preseason games.AIM To compare the incidence of ACL tears through the first eight weeks of the NFL season in 2020 to the mean incidence over the previous 5 seasons(2015-2019)and determine if there was any change in incidence with the elimination of the preseason.METHODS NFL players who suffered ACL tears during the preseason and first eight weeks of the NFL season from 2015-2020 were identified.The number of ACL injuries for the 2015-2019 seasons was compared to the 2020 season for four different timeframes.For each analysis,the cumulative number of ACL injuries to that time point was used to calculate the percent difference for descriptive analysis.Additionally,the number of teams with at least one player suffering an ACL tear were identified and compared using Chi-Squared testing.Finally,a cumulative relative risk was calculated for each week played.RESULTS There were 14 ACL tears through the first four games of the 2020 season,a 118.8%(14 vs 6.4)increase in comparison to the 5-year average over the first 4 regular season weeks of 2015-2019.However,when accounting for injuries occurring during the preseason from 2015-2019,there were 18.6%(14 vs 17.2)fewer total ACL injuries through regular season week 4 with no significant difference in percentage of teams impacted when these preseason injuries were accounted for P=0.394.Results were similar(19 vs 17.2)over 8 total games played(whether regular season or preseason),and over 8 regular season games(P=0.196,P=0.600).CONCLUSION The elimination of the NFL preseason resulted in a higher rate of injuries during the first 4 games of the regular season.However,these increases are offset by the injuries typically sustained during the preseason.This suggests there may be front-loading of injuries over the course of an NFL season,such that players may be more prone to injury when the intensity of play suddenly increases,whether in the preseason or regular season.展开更多
Context and Objective: The nutritional and sports dimension of the lockdown implemented during the COVID-19 pandemic is unexplored in the African environment. The purpose of this study was to assess the effects of COV...Context and Objective: The nutritional and sports dimension of the lockdown implemented during the COVID-19 pandemic is unexplored in the African environment. The purpose of this study was to assess the effects of COVID-19 lockdown on body composition and fitness performance in Congolese football players. Methods: This was an observational study carried out in Brazzaville between February 9 and October 30, 2020. It included 16 male players among Congolese senior national team and 11 male football players of first division Brazzaville clubs. Two types of measurements were carried out: anthropometric measures (height, body mass, total fat percent, lean body mass);physical capacities [30 m sprint, repeated sprint, aerobic endurance (Yo-Yo Intermittent Recovery test), vertical jump (Squat Jump test, Countermovement test)]. The measurements were realized at 4 times: before lockdown (month of february, T0), 1<sup>st</sup> week of june (T1), 1<sup>st</sup> week of september (T2), 1<sup>st</sup> week of october (T3). Data were compared using Student t test, Sokal S test, Anova, Newman-Keuls test (multiple contrasts) and correlation analysis. Results: A significant increase in body mass (p Conclusion: The present data suggest that COVID-19 lockdown promotes weight gain and decreased physical ability in football players.展开更多
This work presents the design of an Expert System that aims to advice the club teams to buy a football player in the post that they needed. Suggesting different player in many posts by an expert person is based on foo...This work presents the design of an Expert System that aims to advice the club teams to buy a football player in the post that they needed. Suggesting different player in many posts by an expert person is based on football experience, knowledge about the player and the club that he works. For mechanization the ability of this person, we use Expert System because it can model the ability of a person in solving a problem. Visual Prolog language is used as a tool for designing our Expert System.展开更多
Background: The injuries sustained in football most frequently occur to the lower extremity, with ankle and knee being the most affected joint segments. Many studies have defined ankle sprain as one of the most common...Background: The injuries sustained in football most frequently occur to the lower extremity, with ankle and knee being the most affected joint segments. Many studies have defined ankle sprain as one of the most common sports injuries with an annual incidence rate of 15% to 45%, however, there’s a lack of studies in football regional leagues. Risk factors like anthropometric measures, field position, dominant limb, previous injury have been described as being associated with ankle injuries in the elite sports context. The primary aim of this study was to determine prevalence rates of self-reported ankle instability in regional leagues. A secondary aim was to explore the presence of extrinsic factors affecting ankle instability in these football players. Methods: The heads of all clubs (n = 66) from Coimbra and Aveiro (Portugal) regional male senior football divisions during season 2016/2017 were contacted by e-mail or telephone to enter the study, and 58 gave their permission to include their athletes. Then, all players from each of these 58 teams were invited to enter the study (n = 1044) and a total of 589 athletes participated. Demographic and anthropometric data were recorded concerning age, height, weight, years of training, mean number of training hours, position in camp along with specific questions related to an ankle injury. All participants were asked about their previous history of injury, reinjury, feeling of giving-away and where also asked to fill the Cumberland Ankle Instability Tool. Results: A total of 290 (49.2%) athletes reported a history of at least one previous sprain and, from these, 170 (58.6%) repeated the injury and 112 (19%) reported sensation of “giving-away”. A significant association was found between injury, recurrence and subjective feeling of giving away (p < 0.05). The player field’s position was found to be associated with ankle instability, with defenders and forwards having higher rates of self-reported instability. No other significant associations were found. Conclusion: Along with intrinsic factors (age and injury repetition), some extrinsic factors were found to be associated with instability rates in professional regional football players (exposure time, and position on the field) suggesting the need for specific prevention strategies.展开更多
While newer, advanced helmet models have been designed with the intentions of decreasing concussions, very little research exists on injury rates in various football helmets at the collegiate level. The aim of this st...While newer, advanced helmet models have been designed with the intentions of decreasing concussions, very little research exists on injury rates in various football helmets at the collegiate level. The aim of this study was to examine concussion injury rates in various models of football helmets in collegiate football athletes. In addition, to compare injury rates of newer, advanced football helmets to older, traditional helmets among collegiate football athletes, a total of 209 concussions and 563,701 AEs （athlete-exposures） among 2,107 collegiate football athletes in seven helmet models were included in the analyses. Concussion injury rates revealed that the Riddell Revolution~ had the highest rate of 0.41 concussions per 1,000 AEs. The Schutt ION 4DTM helmet had the lowest rate of 0.25 concussions per 1,000 AEs. These newer helmet models did not significantly differ from one another （P = 0.74）, however, all models significantly differed from the older, traditional helmet model （P 〈 0.001）. The findings of this study suggest that concussion rates do not differ between newer and more advanced helmet models. More importantly, there are currently no helmets available to prevent concussions from occurring in football athletes.展开更多
The purpose of this study was to investigate the relationship between functional ankle instability and collegiate female football players’ performance. Ankle instability was defined as functional instability based on...The purpose of this study was to investigate the relationship between functional ankle instability and collegiate female football players’ performance. Ankle instability was defined as functional instability based on the Karlsson score. All participants underwent performance tests (Yo-Yo Intermittent Recovery test level 1, 20 m and 40 m Sprint, Bounding test, Shuttle run, Figure-of-8 hop test, and Side hopping). A positive relationship was observed between functional ankle instability and performance deficits on the Figure-of-8 hop test. However, functional ankle instability is thought to have an influence on football performance. In the performance tests, the results suggest the necessity of a new evaluation method with more difficult tests incorporating football movements, subjective “pain” and “instability” indices, and mechanical instability.展开更多
Parasympathetic function can be assessed by the deep breathing test (DB) as a simple and reproducible cardiovascular reflex. The aim of this study is to use this test to compare the vagal response of a young footballe...Parasympathetic function can be assessed by the deep breathing test (DB) as a simple and reproducible cardiovascular reflex. The aim of this study is to use this test to compare the vagal response of a young footballers group to of age-matched untrained normal subjects. Deep breathing test was performed in 2 groups: one of 20 adult young footballers (average age of 19.3 ± 0.6 years), and a second age-matched group of 20 untrained subjects (average age of 19.6 ± 0.6 years). Subjects underwent the DB test after 30 min resting in supine position, and responses were expressed as a percentage of variation of heart rate during the stimulation. Student’s t-test was used to evaluate statistical differences among the two groups for all parameters (vagal response, heart rate, VO2max….) and considering p < 0.05 as a significant difference. The results showed that vagal response to deep breathing test was significantly higher in the young footballers when compared to the untrained controls (72.6% ± 16.2% vs 55.0% ± 12.8%, respectively, p = 0.03). The basal heart rate was significantly lower in footballers than in the controls group (52.1 ± 7.4 bat/min vs 69.8 ± 14.3 bat/min, p < 0.01). The use of the simple test of deep breathing allowed us to demonstrate that adult young footballers have a significantly lower basal HR and higher parasympathetic response in comparison to untrained subjects.展开更多
The paper argues that in the contemporary world,politics and football,especially professional football,are closely connected.This interplay is often expressed through a strong presence of nationalism,both as ideology ...The paper argues that in the contemporary world,politics and football,especially professional football,are closely connected.This interplay is often expressed through a strong presence of nationalism,both as ideology and political practice in the social fields where football and politics overlap.Since Croatia gained its independence,it has been among the countries where many protagonists of the most popular sport and politics are linked by a strong bond.That bond is strongly marked by various shapes of nationalism,from collective perception of the national team as an ideal symbol of the young nation and frequent overstatements of its connection with the nation made by many sympathizers and protagonists of football in Croatia,to chauvinist and politically extremist behaviour of one part of the fans.The essential research question is what the prevalent causes and patterns of use and abuse of nationalism in contemporary Croatian football are.The paper displays the results based on the triangulation of various research methods,particularly the ones that lead to relevant data on the complex and diverse(objective,subjective,and constructed)experience of nationalism among the organized fans in Croatia,to observing and participating,talking with fan club members,to exploring media production and political communication pertinent to this topic.展开更多
Greenhouse gas (GHG) emission from waste is a major environmental problem. Globally, the waste management sector contributes an estimated 5% of the total anthropogenic GHG emissions. This paper estimates GHG emissions...Greenhouse gas (GHG) emission from waste is a major environmental problem. Globally, the waste management sector contributes an estimated 5% of the total anthropogenic GHG emissions. This paper estimates GHG emissions from football clubs in the England, where football is the highest profile and most popular sport, with large numbers of spectators and significant quantities of waste being produced. Football clubs should be more committed to reducing their GHG emissions by improving their waste management. The amount of GHG emitted from eight football tiers in England is assessed through methods including interviews, observations and questionnaires. The results reveal that in the 2012/13-football season, over 9 million spectators watched football in the lower leagues, with mean waste per spectator of 3.27 kg. 30,146,000 kg of waste was generated at the 8 football tiers, and the amount of waste sent to the landfill was about 74,000,000 kg, which resulted in GHG emissions of approximately 2,100,000 kg CO2e. The implications for better waste management at football leagues are outlined.展开更多
The evaluation of education in the training process is important for students, and its importance is at the level of students and thecorresponding level of evaluation. Understanding the guidance and training of the mi...The evaluation of education in the training process is important for students, and its importance is at the level of students and thecorresponding level of evaluation. Understanding the guidance and training of the middle school football team is an important partof rapidly improving the level of Chinese football. It is necessary to adapt to the development characteristics of middle schoolstudents and conduct reasonable guidance training. Plans must be strengthened to implement training programs. On the trainingschedule, we must balance learning and training, and must fully consider the growth of students. As part of a layered education,stratified evaluation has the unique advantages of basic education and secondary education. The evaluation of the students whofocus on various levels of learning. Football coaching and training requires a full display of the student's personality. The teacher'sstratified evaluation method is very important for improving students' confidence in learning, enhancing students' enthusiasm forfootball training, and promoting students' continuous improvement. This study takes the application of stratified evaluation in theteaching and training of middle school football as the research direction, and puts forward reasonable suggestions by analyzing thetraining cases of the layered evaluation.展开更多
文摘Football is one of the most-watched sports,but analyzing players’per-formance is currently difficult and labor intensive.Performance analysis is done manually,which means that someone must watch video recordings and then log each player’s performance.This includes the number of passes and shots taken by each player,the location of the action,and whether or not the play had a successful outcome.Due to the time-consuming nature of manual analyses,interest in automatic analysis tools is high despite the many interdependent phases involved,such as pitch segmentation,player and ball detection,assigning players to their teams,identifying individual players,activity recognition,etc.This paper proposes a system for developing an automatic video analysis tool for sports.The proposed system is the first to integrate multiple phases,such as segmenting the field,detecting the players and the ball,assigning players to their teams,and iden-tifying players’jersey numbers.In team assignment,this research employed unsu-pervised learning based on convolutional autoencoders(CAEs)to learn discriminative latent representations and minimize the latent embedding distance between the players on the same team while simultaneously maximizing the dis-tance between those on opposing teams.This paper also created a highly accurate approach for the real-time detection of the ball.Furthermore,it also addressed the lack of jersey number datasets by creating a new dataset with more than 6,500 images for numbers ranging from 0 to 99.Since achieving a high perfor-mance in deep learning requires a large training set,and the collected dataset was not enough,this research utilized transfer learning(TL)to first pretrain the jersey number detection model on another large dataset and then fine-tune it on the target dataset to increase the accuracy.To test the proposed system,this paper presents a comprehensive evaluation of its individual stages as well as of the sys-tem as a whole.
文摘Based on the “Healthy China 2030 Planning Outline”, the literature method and logical analysis method are used to review and analyze the implementation process of China’s school football policy from three dimensions: value, interest appeal and institutional background. The study believes that in order to break through the bottleneck of policy implementation and improve the effect of policy implementation, it is necessary to establish correct values and form broad recognition of policies;meet the reasonable interests of all parties and form a synergy for policy implementation;optimize the institutional environment for policy implementation and form effective incentives.
文摘Football is the most popular sport worldwide and is associated with a high injury rate, most of which are the result of trauma from player contact. Ankle injuries are among the most commonly diagnosed injuries in the game. The result is reduced physical activity and endurance levels, lost game time, and considerable medical cost. Sports medicine professionals must employ the correct diagnostic tools and effective treatments and rehabilitation protocols to minimize the impact of these injuries on the player. This review examines the diagnosis, treatment, and postoperative rehabilitation for common football injuries of the ankle based on the clinical evidence provided in the current literature.
文摘BACKGROUND Flexibility,agility and muscle strength are key factors to either win or lose a game.Recently the effect of a new technique,deep transverse friction massage(DTFM)on muscle extensibility as compared to traditional stretching techniques has been examined.AIM To compare the effect of DTFM vs static and dynamic stretching techniques on the hamstring’s extensibility,agility,and strength amongst Lebanese and Syrian football players.Recording the incidence of non-contact hamstring muscle injury was a secondary objective.METHODS This study is a single-blinded prospective longitudinal randomized controlled trial.The experiment took place over a period of four weeks.Football players were randomized into three intervention groups(static stretching;dynamic stretching;DTFM).Participants of each group were followed-up carefully by assessors during their intervention sessions three times per week,for a total of 12 sessions and during the data collection.Extensibility,agility,and strength were compared between intervention groups at(baseline;acute;and chronic)phases.Straight leg raise and 1 repetition maximum tests were used to measure the dominant leg hamstring muscle extensibility and maximal strength respectively.T-drill test was used to assess the lower extremities agility.RESULTS Of 103 Lebanese and Syrian male football players aged between 18 and 35 were sampled from Damascus-Syria and South of Lebanon to participate in this study.Between-groups measures of acute strength(P=0.011)and chronic extensibility(P=0.000)solely showed a significant difference,and the static group showed to be superior as compared to the other groups.No loss to follow-up or protocol violation was recorded.CONCLUSION Static stretching is showing to be superior to the other techniques used,regarding gaining long-term extensibility and short-term maximal muscle strength.In addition,DTFM showed improvements but did not outweigh the effects on footballers’performance when comparing it to static and dynamic techniques.Finally,no difference between the interventions is recorded regarding the rate of muscle injuries incidence.
文摘In this paper, we utilize Data Envelopment Analysis (DEA), which is a linear programming-based technique, for evaluating the performance of the teams which operate in the Iranian primer football league. We use Analytical Hierarchy Process (AHP) technique for aggregating the sub-factors which involve in input-output factors, and then DEA is used for calculating the efficiency measures. Also, AHP is used to construct some weight restrictions for increasing the discrimination power of the used DEA model. For calculating the efficiency measures, input-oriented weight-restricted BCC model is utilized.
文摘Background: A cardiovascular assessment is rarely performed among athletes despite more and more frequently reported fatal events. Most of these accidents are of cardiovascular origin. Moreover, data on ECG or Echocardiography are rare in our context justifying our study to assess electrical and echocardiographic pattern among high-level footballer in Bamako. Methods: It was a cross-sectional study conducted in Bamako from April 2015 to?March 2016 among high-level footballers aged 14 to 35 years old without distinction of sex with at least 10 hours weekly training since one year. The ECG and echocardiographies were recorded respectively with a 12-lead CONTEC and an ATL 5000 echocardiographic machine. Each ECG record was analyzed by a cardiologist in accordance with the Seattle 2013 criteria and those pathological reviewed by a second cardiologist according to the same criteria and definitively classified as normal (physiological) or abnormal ECG (requiring complementary explorations). A third cardiologist was associated in case of discordance of the first results. The collected data were inserted in a Microsoft Excel sheet and analyzed with SPSS version 20. Chi Square and Fisher statistical tests were used to compare our results. The significance level was set at 0.05. Results: We collected data of 227 top footballers with male sex represented in 90.3% giving a sex ratio of 3.04. Means for age, weight, height, body mass index (BMI) were respectively 22 years, 69.90 kg, 177.21 cm and 22.21 kg/m2. Sinus bradycardia was found in a proportion of 45.8% more represented in the age group of 30 and more years (p = 0.275). First-degree atrioventricular block (AVB) was present in 19.4%. Short PR was found in 0.4% of the sample. Left ventricular hypertrophy (LVG) according to the Sokolow index was found in 70.5% (96.9% males and 3.1% females) with p Conclusion: Many electrical and echocardiographic signs of cardiac adaptation were found in our sample and must lead to a closer follow-up of these trained footballers to avoid or prevent dramatic cardiovascular events.
文摘Context and Objective: Hamstring strain is a common injury in football and it causes a significant amount of time lost from competition and training. Since poor flexibility is thought to predispose to muscle strain, stretching is routinely recommended during warm-up routines by coaches to prevent injuries. However, available evidence suggests that pre-exercise stretching (PES), especially static stretching, has no benefit on injury rates and may even reduce performance in explosive type activities. We designed this study to assess the attitudes, beliefs and practices of football coaches regarding stretching in the prevention of hamstring strains. Design: A cross-sectional survey. Setting: Mauritius Football Association (MFA). Participants: 26 football coaches registered with the MFA. Intervention: Questionnaires were distributed to football coaches of the MFA via sports officers. Questionnaires were then collected two weeks after distribution. Main Outcome Measures: Attitudes, beliefs and practices of football coaches regarding stretching in the prevention of ham-string strains. Results: MFA coaches held generally positive attitudes and beliefs towards stretching. 88% of coaches felt that PES is beneficial and 93% believed that PES prevents hamstring strains. The majority of coaches recommended stretching after warming up (81%) and after the training session (93%). 76% of coaches also advised stretching outside the training sessions. 96% of coaches used static stretching to stretch the hamstrings. The hamstrings were stretched on average for 4 times at each training session and the mean duration of a static stretch was 12 seconds. Conclusions: Nearly all coaches believed that PES prevents hamstring strains although evidence is limited. Some of the coaches’ beliefs and practices were not in line with current recommendations. Coaches reported that their stretching practices would be most likely influenced by scientific research. Thus there is an urgent need to devise awareness and training programmes in this area.
文摘BACKGROUND Anterior cruciate ligament(ACL)injuries represent detrimental injuries in the National Football League(NFL).A significant portion of these injuries often occur in preseason exhibitions.The Coronavirus disease 2019 pandemic presented a unique disruption to preseason NFL football with the cancelation of all preseason games.AIM To compare the incidence of ACL tears through the first eight weeks of the NFL season in 2020 to the mean incidence over the previous 5 seasons(2015-2019)and determine if there was any change in incidence with the elimination of the preseason.METHODS NFL players who suffered ACL tears during the preseason and first eight weeks of the NFL season from 2015-2020 were identified.The number of ACL injuries for the 2015-2019 seasons was compared to the 2020 season for four different timeframes.For each analysis,the cumulative number of ACL injuries to that time point was used to calculate the percent difference for descriptive analysis.Additionally,the number of teams with at least one player suffering an ACL tear were identified and compared using Chi-Squared testing.Finally,a cumulative relative risk was calculated for each week played.RESULTS There were 14 ACL tears through the first four games of the 2020 season,a 118.8%(14 vs 6.4)increase in comparison to the 5-year average over the first 4 regular season weeks of 2015-2019.However,when accounting for injuries occurring during the preseason from 2015-2019,there were 18.6%(14 vs 17.2)fewer total ACL injuries through regular season week 4 with no significant difference in percentage of teams impacted when these preseason injuries were accounted for P=0.394.Results were similar(19 vs 17.2)over 8 total games played(whether regular season or preseason),and over 8 regular season games(P=0.196,P=0.600).CONCLUSION The elimination of the NFL preseason resulted in a higher rate of injuries during the first 4 games of the regular season.However,these increases are offset by the injuries typically sustained during the preseason.This suggests there may be front-loading of injuries over the course of an NFL season,such that players may be more prone to injury when the intensity of play suddenly increases,whether in the preseason or regular season.
文摘Context and Objective: The nutritional and sports dimension of the lockdown implemented during the COVID-19 pandemic is unexplored in the African environment. The purpose of this study was to assess the effects of COVID-19 lockdown on body composition and fitness performance in Congolese football players. Methods: This was an observational study carried out in Brazzaville between February 9 and October 30, 2020. It included 16 male players among Congolese senior national team and 11 male football players of first division Brazzaville clubs. Two types of measurements were carried out: anthropometric measures (height, body mass, total fat percent, lean body mass);physical capacities [30 m sprint, repeated sprint, aerobic endurance (Yo-Yo Intermittent Recovery test), vertical jump (Squat Jump test, Countermovement test)]. The measurements were realized at 4 times: before lockdown (month of february, T0), 1<sup>st</sup> week of june (T1), 1<sup>st</sup> week of september (T2), 1<sup>st</sup> week of october (T3). Data were compared using Student t test, Sokal S test, Anova, Newman-Keuls test (multiple contrasts) and correlation analysis. Results: A significant increase in body mass (p Conclusion: The present data suggest that COVID-19 lockdown promotes weight gain and decreased physical ability in football players.
文摘This work presents the design of an Expert System that aims to advice the club teams to buy a football player in the post that they needed. Suggesting different player in many posts by an expert person is based on football experience, knowledge about the player and the club that he works. For mechanization the ability of this person, we use Expert System because it can model the ability of a person in solving a problem. Visual Prolog language is used as a tool for designing our Expert System.
文摘Background: The injuries sustained in football most frequently occur to the lower extremity, with ankle and knee being the most affected joint segments. Many studies have defined ankle sprain as one of the most common sports injuries with an annual incidence rate of 15% to 45%, however, there’s a lack of studies in football regional leagues. Risk factors like anthropometric measures, field position, dominant limb, previous injury have been described as being associated with ankle injuries in the elite sports context. The primary aim of this study was to determine prevalence rates of self-reported ankle instability in regional leagues. A secondary aim was to explore the presence of extrinsic factors affecting ankle instability in these football players. Methods: The heads of all clubs (n = 66) from Coimbra and Aveiro (Portugal) regional male senior football divisions during season 2016/2017 were contacted by e-mail or telephone to enter the study, and 58 gave their permission to include their athletes. Then, all players from each of these 58 teams were invited to enter the study (n = 1044) and a total of 589 athletes participated. Demographic and anthropometric data were recorded concerning age, height, weight, years of training, mean number of training hours, position in camp along with specific questions related to an ankle injury. All participants were asked about their previous history of injury, reinjury, feeling of giving-away and where also asked to fill the Cumberland Ankle Instability Tool. Results: A total of 290 (49.2%) athletes reported a history of at least one previous sprain and, from these, 170 (58.6%) repeated the injury and 112 (19%) reported sensation of “giving-away”. A significant association was found between injury, recurrence and subjective feeling of giving away (p < 0.05). The player field’s position was found to be associated with ankle instability, with defenders and forwards having higher rates of self-reported instability. No other significant associations were found. Conclusion: Along with intrinsic factors (age and injury repetition), some extrinsic factors were found to be associated with instability rates in professional regional football players (exposure time, and position on the field) suggesting the need for specific prevention strategies.
文摘While newer, advanced helmet models have been designed with the intentions of decreasing concussions, very little research exists on injury rates in various football helmets at the collegiate level. The aim of this study was to examine concussion injury rates in various models of football helmets in collegiate football athletes. In addition, to compare injury rates of newer, advanced football helmets to older, traditional helmets among collegiate football athletes, a total of 209 concussions and 563,701 AEs （athlete-exposures） among 2,107 collegiate football athletes in seven helmet models were included in the analyses. Concussion injury rates revealed that the Riddell Revolution~ had the highest rate of 0.41 concussions per 1,000 AEs. The Schutt ION 4DTM helmet had the lowest rate of 0.25 concussions per 1,000 AEs. These newer helmet models did not significantly differ from one another （P = 0.74）, however, all models significantly differed from the older, traditional helmet model （P 〈 0.001）. The findings of this study suggest that concussion rates do not differ between newer and more advanced helmet models. More importantly, there are currently no helmets available to prevent concussions from occurring in football athletes.
文摘The purpose of this study was to investigate the relationship between functional ankle instability and collegiate female football players’ performance. Ankle instability was defined as functional instability based on the Karlsson score. All participants underwent performance tests (Yo-Yo Intermittent Recovery test level 1, 20 m and 40 m Sprint, Bounding test, Shuttle run, Figure-of-8 hop test, and Side hopping). A positive relationship was observed between functional ankle instability and performance deficits on the Figure-of-8 hop test. However, functional ankle instability is thought to have an influence on football performance. In the performance tests, the results suggest the necessity of a new evaluation method with more difficult tests incorporating football movements, subjective “pain” and “instability” indices, and mechanical instability.
文摘Parasympathetic function can be assessed by the deep breathing test (DB) as a simple and reproducible cardiovascular reflex. The aim of this study is to use this test to compare the vagal response of a young footballers group to of age-matched untrained normal subjects. Deep breathing test was performed in 2 groups: one of 20 adult young footballers (average age of 19.3 ± 0.6 years), and a second age-matched group of 20 untrained subjects (average age of 19.6 ± 0.6 years). Subjects underwent the DB test after 30 min resting in supine position, and responses were expressed as a percentage of variation of heart rate during the stimulation. Student’s t-test was used to evaluate statistical differences among the two groups for all parameters (vagal response, heart rate, VO2max….) and considering p < 0.05 as a significant difference. The results showed that vagal response to deep breathing test was significantly higher in the young footballers when compared to the untrained controls (72.6% ± 16.2% vs 55.0% ± 12.8%, respectively, p = 0.03). The basal heart rate was significantly lower in footballers than in the controls group (52.1 ± 7.4 bat/min vs 69.8 ± 14.3 bat/min, p < 0.01). The use of the simple test of deep breathing allowed us to demonstrate that adult young footballers have a significantly lower basal HR and higher parasympathetic response in comparison to untrained subjects.
文摘The paper argues that in the contemporary world,politics and football,especially professional football,are closely connected.This interplay is often expressed through a strong presence of nationalism,both as ideology and political practice in the social fields where football and politics overlap.Since Croatia gained its independence,it has been among the countries where many protagonists of the most popular sport and politics are linked by a strong bond.That bond is strongly marked by various shapes of nationalism,from collective perception of the national team as an ideal symbol of the young nation and frequent overstatements of its connection with the nation made by many sympathizers and protagonists of football in Croatia,to chauvinist and politically extremist behaviour of one part of the fans.The essential research question is what the prevalent causes and patterns of use and abuse of nationalism in contemporary Croatian football are.The paper displays the results based on the triangulation of various research methods,particularly the ones that lead to relevant data on the complex and diverse(objective,subjective,and constructed)experience of nationalism among the organized fans in Croatia,to observing and participating,talking with fan club members,to exploring media production and political communication pertinent to this topic.
文摘Greenhouse gas (GHG) emission from waste is a major environmental problem. Globally, the waste management sector contributes an estimated 5% of the total anthropogenic GHG emissions. This paper estimates GHG emissions from football clubs in the England, where football is the highest profile and most popular sport, with large numbers of spectators and significant quantities of waste being produced. Football clubs should be more committed to reducing their GHG emissions by improving their waste management. The amount of GHG emitted from eight football tiers in England is assessed through methods including interviews, observations and questionnaires. The results reveal that in the 2012/13-football season, over 9 million spectators watched football in the lower leagues, with mean waste per spectator of 3.27 kg. 30,146,000 kg of waste was generated at the 8 football tiers, and the amount of waste sent to the landfill was about 74,000,000 kg, which resulted in GHG emissions of approximately 2,100,000 kg CO2e. The implications for better waste management at football leagues are outlined.
文摘The evaluation of education in the training process is important for students, and its importance is at the level of students and thecorresponding level of evaluation. Understanding the guidance and training of the middle school football team is an important partof rapidly improving the level of Chinese football. It is necessary to adapt to the development characteristics of middle schoolstudents and conduct reasonable guidance training. Plans must be strengthened to implement training programs. On the trainingschedule, we must balance learning and training, and must fully consider the growth of students. As part of a layered education,stratified evaluation has the unique advantages of basic education and secondary education. The evaluation of the students whofocus on various levels of learning. Football coaching and training requires a full display of the student's personality. The teacher'sstratified evaluation method is very important for improving students' confidence in learning, enhancing students' enthusiasm forfootball training, and promoting students' continuous improvement. This study takes the application of stratified evaluation in theteaching and training of middle school football as the research direction, and puts forward reasonable suggestions by analyzing thetraining cases of the layered evaluation.
