Anthropometric and Physical Performance Profiles of High School Age American Football Players: 11th and 12th Grade Japanese Athletes

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.

Genetic Testing in Professional Football:Perspectives of Key Stakeholders

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.

Does Resisted Sled Towing Improve the Physical Qualities of Elite Youth Soccer Players of Differing Maturity Status?

Purpose Sled towing has been shown to be an effective method to enhance the physical qualities in youth athletes.The aim of this study was to evaluate the impact of a 6-week sled towing intervention on muscular strength,speed and power in elite youth soccer players of differing maturity status.Method Seventy-three male elite youth soccer players aged 12-18 years(Pre-Peak Height Velocity[PHV]n = 25;Circa-PHV n = 24;Post-PHV n = 24)from one professional soccer academy participated in this study.Sprint assessments(10 m and 30 m),countermovement jump and isometric mid-thigh pull were undertaken before(T1)and after(T2)a 6-week intervention.The training intervention consisted of 6 weeks(2xper week,10 sprints over 20 m distance)of resisted sled towing(linear progression 10%-30%of body mass)during the competitive season.Bayesian regression models analysed differences between T1 and T2 within each maturity group.Results There were minimal changes in strength,speed and power(P=0.35-0.80)for each maturity group across the 6-week intervention.Where there were changes with greater certainty,they are unlikely to represent real effect due to higher regres-sion to the mean(RTM).Conclusion It appears that a 6-week sled towing training programme with loadings of 10%-30%body mass only maintains physical qualities in elite youth soccer players pre-,circa-,and post-PHV.Further research is required to determine the effectiveness of this training method in long-term athletic development programmes.