Purpose To compare anthropometric and physical performance profiles of Japanese 11th and 12th grade American football players within each positional group.Methods Fifty-two 11th and 12th grade American football player...Purpose To compare anthropometric and physical performance profiles of Japanese 11th and 12th grade American football players within each positional group.Methods Fifty-two 11th and 12th grade American football players from two Japanese high schools participated in the study during the summer pre-season period.They performed anthropometric(height and body mass)and physical(vertical jump,broad jump,40-yard dash,pro-agility shuttle 4-kg medicine ball chest throw,front throw,and back throw)testing.Vertical jump momentum and 10-yard sprint momentum were also calculated by multiplying the velocity and body mass.Athletes were divided into two groups by playing positions:skill players and linemen.Results Skill players in the 12th grade were better at medicine ball chest throw(d=0.73,P=0.04)and vertical jump momen-tum(d=0.75,P=0.03)than those in the 11th grade.However,there were no differences in any measurements(P>0.05)between linemen from the two grades.Conclusion The current study suggests that upper and lower body absolute power and momentum production can be improved for skill players even over 17 years old.On the other hand,body size and speed,attributes that did not change between 11th and 12th grades,seem to be essential talent identification criteria in the current environment.Further study is needed to monitor longitudinal performance improvements in implementing talent development programs by focusing on the quality of speed,agility and power development at the youth level.展开更多
The world's greatest professional football players are able to execute effective tactical decisions as well as fulfil various physical demands.However,the degree to which both are associated with greater potential...The world's greatest professional football players are able to execute effective tactical decisions as well as fulfil various physical demands.However,the degree to which both are associated with greater potential in a football academy is unknown.Therefore,the aim of this study was to investigate decision-making skill and physical performance as contributing factors to coach potential rankings in an English football academy.Ninety-eight outfield academy players(Foundation Development Phase[FDP]under-9 to under-11 n=40;Youth Development Phase[YDP]under-12 to under-16 n=58)participated in the study.They engaged in 45 film-based simulations at two occlusion phases(e.g.,the visual display is cut-off at a precise time during an action),firstly"during"and secondly"post"execution,to examine decision-making skill.Participants also completed four fitness tests to examine physical performance.A classification of"higher-potentials"(top third)and"lower-potentials"(bottom third)were applied through coach rankings.Independent t-tests compared the decision-making and physical performance tests.Higher-potentials made significantly more accurate decisions within the"post"phase within the FDP(P<0.05)and the"during"phase within the YDP(P<0.05).Additionally,higher-potentials were significantly faster for the 0-30 m sprint in both the FDP and YDP(P<0.05),with higher-potentials within the YDP also significantly faster in the 0-10 m sprint(P<0.05)and jumped significantly higher in the countermovement jump(P<0.05).These findings indicated that greater football potential may be associated with superior perceptual-cognitive expertise and quicker sprint ability in both academy age phases,with a greater discriminatory function within the older cohort.展开更多
Purpose Genetic research in football is currently in it’s infancy but is growing rapidly.However,the practical application of genetic testing in football and the views concerning its use are unknown.Thus,the purpose ...Purpose Genetic research in football is currently in it’s infancy but is growing rapidly.However,the practical application of genetic testing in football and the views concerning its use are unknown.Thus,the purpose of this study was to assess the current practical application of genetic testing in professional football and provide an insight into the perspectives of key stakeholders(i.e.,coaches,practitioners,players).Methods In total,122 participants completed an online anonymous survey.This consisted of 21 multiple choice and Likert scale questions,with the option of providing an explanation for each response.Results Findings revealed genetic testing is rarely utilised by key stakeholders(10%)or their respective organisations(14%).However,three quarters(75%)had the opinion that genetic testing will have great utility in the future.The majority(72%)believed genetic testing should be used for athlete development and injury risk,whilst 35%believed that genetic testing should be utilised for talent identification purposes.However,most key stakeholders viewed their own(89%)and their col-leagues’(79%)knowledge related to genetic testing as insufficient;mainly due to ineffective current communication methods(91%).Most believed educational workshops are required(71%),whilst nearly all(91%)were interested in developing their expertise on the utility of genetic testing.Conclusion Genetic testing is rarely used within professional football,although key stakeholders anticipate that it will be utilised more in the future.As such,educational support may prove valuable in improving key stakeholder knowledge and the practical application of genetic testing in professional football.展开更多
Purpose The aim of this study was to investigate the prevalence of the ACTN3 rs1815739 polymorphism and to study its association with athletes'level of competition and lower-extremity power.Method Time-of-flight m...Purpose The aim of this study was to investigate the prevalence of the ACTN3 rs1815739 polymorphism and to study its association with athletes'level of competition and lower-extremity power.Method Time-of-flight mass spectrometry(TOFMS)and polymerase chain reaction-restriction fragment length polymor-phism(PCR-RFLP)techniques were employed to identify the ACTN3 rs1815739 genotypes and allele frequencies in 108 elite sprinters and 206 untrained controls.Questionnaires were then used to assess subjects'100 m sprint,standing jump(SJ)and standing triple jump(STJ)personal best record.Results(1)The RR,RX and XX genotype distribution of the ACTN3 rs1815739 polymorphism is 42.6%,49.1%,8.3%,respectively.R and X alleles frequency is 67.1%and 32.9%,respectively,which comply with Hardy Weinberg equilibrium(HWE)through Chi-square(x2)tests(x2=0.661;df=2;P=0.718).(2)Significant differences were found in R allele fre-quency between the elite sprinter group and controls.(3)The athletes'100 m sprint,SJ,and STJ personal best records were better in those with RR and RX than XX genotype.A significant association was observed between the R alleles and 100 m sprint,SJ,and STJ results of male and female athletes.Conclusion The present results indicate that ACTN3 rs1815739 polymorphism has a significant association with speed and lower-extremity power in sprint/power athletes.展开更多
基金funded by JSPS KAKENHI,Grant Number 16K16557 and JSC High Performance Center Total Conditioning Research Project.
文摘Purpose To compare anthropometric and physical performance profiles of Japanese 11th and 12th grade American football players within each positional group.Methods Fifty-two 11th and 12th grade American football players from two Japanese high schools participated in the study during the summer pre-season period.They performed anthropometric(height and body mass)and physical(vertical jump,broad jump,40-yard dash,pro-agility shuttle 4-kg medicine ball chest throw,front throw,and back throw)testing.Vertical jump momentum and 10-yard sprint momentum were also calculated by multiplying the velocity and body mass.Athletes were divided into two groups by playing positions:skill players and linemen.Results Skill players in the 12th grade were better at medicine ball chest throw(d=0.73,P=0.04)and vertical jump momen-tum(d=0.75,P=0.03)than those in the 11th grade.However,there were no differences in any measurements(P>0.05)between linemen from the two grades.Conclusion The current study suggests that upper and lower body absolute power and momentum production can be improved for skill players even over 17 years old.On the other hand,body size and speed,attributes that did not change between 11th and 12th grades,seem to be essential talent identification criteria in the current environment.Further study is needed to monitor longitudinal performance improvements in implementing talent development programs by focusing on the quality of speed,agility and power development at the youth level.
基金funded by the University of Exeter,College of Life&Environmental Sciences,the Open Innovation Platform at the University of Exeter,and Exeter City Football Club Academy.
文摘The world's greatest professional football players are able to execute effective tactical decisions as well as fulfil various physical demands.However,the degree to which both are associated with greater potential in a football academy is unknown.Therefore,the aim of this study was to investigate decision-making skill and physical performance as contributing factors to coach potential rankings in an English football academy.Ninety-eight outfield academy players(Foundation Development Phase[FDP]under-9 to under-11 n=40;Youth Development Phase[YDP]under-12 to under-16 n=58)participated in the study.They engaged in 45 film-based simulations at two occlusion phases(e.g.,the visual display is cut-off at a precise time during an action),firstly"during"and secondly"post"execution,to examine decision-making skill.Participants also completed four fitness tests to examine physical performance.A classification of"higher-potentials"(top third)and"lower-potentials"(bottom third)were applied through coach rankings.Independent t-tests compared the decision-making and physical performance tests.Higher-potentials made significantly more accurate decisions within the"post"phase within the FDP(P<0.05)and the"during"phase within the YDP(P<0.05).Additionally,higher-potentials were significantly faster for the 0-30 m sprint in both the FDP and YDP(P<0.05),with higher-potentials within the YDP also significantly faster in the 0-10 m sprint(P<0.05)and jumped significantly higher in the countermovement jump(P<0.05).These findings indicated that greater football potential may be associated with superior perceptual-cognitive expertise and quicker sprint ability in both academy age phases,with a greater discriminatory function within the older cohort.
文摘Purpose Genetic research in football is currently in it’s infancy but is growing rapidly.However,the practical application of genetic testing in football and the views concerning its use are unknown.Thus,the purpose of this study was to assess the current practical application of genetic testing in professional football and provide an insight into the perspectives of key stakeholders(i.e.,coaches,practitioners,players).Methods In total,122 participants completed an online anonymous survey.This consisted of 21 multiple choice and Likert scale questions,with the option of providing an explanation for each response.Results Findings revealed genetic testing is rarely utilised by key stakeholders(10%)or their respective organisations(14%).However,three quarters(75%)had the opinion that genetic testing will have great utility in the future.The majority(72%)believed genetic testing should be used for athlete development and injury risk,whilst 35%believed that genetic testing should be utilised for talent identification purposes.However,most key stakeholders viewed their own(89%)and their col-leagues’(79%)knowledge related to genetic testing as insufficient;mainly due to ineffective current communication methods(91%).Most believed educational workshops are required(71%),whilst nearly all(91%)were interested in developing their expertise on the utility of genetic testing.Conclusion Genetic testing is rarely used within professional football,although key stakeholders anticipate that it will be utilised more in the future.As such,educational support may prove valuable in improving key stakeholder knowledge and the practical application of genetic testing in professional football.
基金supported by Fundamental Research Funds for the Central Universities under Grant 2017SYS001.
文摘Purpose The aim of this study was to investigate the prevalence of the ACTN3 rs1815739 polymorphism and to study its association with athletes'level of competition and lower-extremity power.Method Time-of-flight mass spectrometry(TOFMS)and polymerase chain reaction-restriction fragment length polymor-phism(PCR-RFLP)techniques were employed to identify the ACTN3 rs1815739 genotypes and allele frequencies in 108 elite sprinters and 206 untrained controls.Questionnaires were then used to assess subjects'100 m sprint,standing jump(SJ)and standing triple jump(STJ)personal best record.Results(1)The RR,RX and XX genotype distribution of the ACTN3 rs1815739 polymorphism is 42.6%,49.1%,8.3%,respectively.R and X alleles frequency is 67.1%and 32.9%,respectively,which comply with Hardy Weinberg equilibrium(HWE)through Chi-square(x2)tests(x2=0.661;df=2;P=0.718).(2)Significant differences were found in R allele fre-quency between the elite sprinter group and controls.(3)The athletes'100 m sprint,SJ,and STJ personal best records were better in those with RR and RX than XX genotype.A significant association was observed between the R alleles and 100 m sprint,SJ,and STJ results of male and female athletes.Conclusion The present results indicate that ACTN3 rs1815739 polymorphism has a significant association with speed and lower-extremity power in sprint/power athletes.
