AIM To study the effect of balance intervention program using the "FIFA 11+" program on static and dynamic balance and kicking accuracy of young soccer players.METHODS Twenty young soccer players were alloca...AIM To study the effect of balance intervention program using the "FIFA 11+" program on static and dynamic balance and kicking accuracy of young soccer players.METHODS Twenty young soccer players were allocated to experimental(n = 10) or control(n = 10) groups. The experimental group performed the "FIFA 11+" program three times a week for six weeks. The control group performed their normal warm-up routine. The primary outcomes were measured pre and post intervention, and assessed kicking accuracy, static balance and dynamic balance.RESULTS No differences were found in kicking accuracy following intervention, for both groups, however, static balance improved significantly among the experimental group with significant interaction with the control group, and with high effect size. In addition, the dynamic balance of the left leg of the experimental group, with medium effect size for interaction between groups.CONCLUSION The large effect size of balance improvement that was observed following six weeks of intervention sessions, implies that soccer trainers and coaches should consider the inclusion of "FIFA 11+" as components of programs aimed at improving balance ability/control in young soccer players, as improvement in balance abilities may prevent injuries.展开更多
Purpose:The purpose of this study was to investigate the influence of fatigue upon kicking maximal ball velocity and the target-hitting accuracy of soccer players;and also to examine the effect of the knowledge of the...Purpose:The purpose of this study was to investigate the influence of fatigue upon kicking maximal ball velocity and the target-hitting accuracy of soccer players;and also to examine the effect of the knowledge of the exercise duration upon these 2 parameters.Methods:Twenty-four semi-professional soccer players participated in this study and performed maximal instep kicks before and after the implementation of an exercise protocol,either with or without knowledge of the duration of this protocol.Results:A mixed model of analysis of variance showed that kicking maximal ball velocity was significantly affected(F(5,85)=11.6,p<0.001,η^2=0.39) but only after just 1 circuit of the fatigue protocol and then remained similar.Accuracy did not change during the protocol(F(5,75)=0.23,p=0.76,η^2=0.03) and knowing the duration of exercitation did not affect accuracy and velocity development(F(1,23) ≤1.04,p≥0.32,η~2≤0.06).Conclusion:These findings demonstrated the potential negative effects of fatigue on kicking ball velocity in soccer but not in the kicking accuracy and that the effect of fatigue may not be progressive over time.Knowing or not knowing the duration of exercitation did not affect the results.展开更多
Purpose: The aim of this study was to investigate the influence of different exercise intensities induced by a soccer specific protocol on kicking performance in soccer players.Methods: Twelve semi-professional male s...Purpose: The aim of this study was to investigate the influence of different exercise intensities induced by a soccer specific protocol on kicking performance in soccer players.Methods: Twelve semi-professional male soccer players participated in this study and performed maximal instep kicks before and after the implementation of an exercise protocol to determine the influence of different intensities upon kicking ball velocity and the target-hitting accuracy.Results: Analysis of variance designs with repeated measures showed that maximal ball velocity was affected only after the most intense circuit(F(6, 66) = 2.3; p = 0.041; η2= 0.18), while accuracy was not affected in the protocol(F(6, 66) = 0.19; p = 0.98; η2= 0.02). Low and moderate intensities did not affect accuracy or kicking ball velocity.Conclusion: These findings suggest that kicking ball velocity is influenced by high-exercise intensities. Low and moderate exercise intensities do not affect the performance of the kick, and intensity does not influence accuracy. Otherwise, it is possible that other mechanisms(not only physiological) may influence players during the exercise.展开更多
Kenya builds East Africa’s biggest kungfu academy as Chinese martial arts gain popularity KUNGFU has been a life-long passion for 21-year-old Kamau Mutunga who recently signed up for martial arts classes after a viol...Kenya builds East Africa’s biggest kungfu academy as Chinese martial arts gain popularity KUNGFU has been a life-long passion for 21-year-old Kamau Mutunga who recently signed up for martial arts classes after a violent attack left him shaken and distressed.展开更多
HE＇D been addicted to drugs and alcohol for 22 years, depending daily on doses of cocaine, marijuana and heroin. To survive, Kenyan John Mugenda, 44, resorted to drastic measures.
Floquet dynamical quantum phase transitions(DQPTs),which are nonanalytic phenomena recuring periodically in time-periodic driven quantum many-body systems,have been widely studied in recent years.In this article,the F...Floquet dynamical quantum phase transitions(DQPTs),which are nonanalytic phenomena recuring periodically in time-periodic driven quantum many-body systems,have been widely studied in recent years.In this article,the Floquet DQPTs in transverse XY spin chains under the modulation ofδ-function periodic kickings are investigated.We analytically solve the system,and by considering the eigenstate as well as the ground state as the initial state of the Floquet dynamics,we study the corresponding multiple Floquet DQPTs emerged in the micromotion with different kicking moments.The rate function of return amplitude,the Pancharatnam geometric phase and the dynamical topological order parameter are calculated,which consistently verify the emergence of Floquet DQPTs in the system.展开更多
Known for their vintage-i nspired parties,cabaret-themed revelries and all-aro und debauchery,event compa ny Kick the Gong Around(KTGA)has been kicking the 20s in Shanghai like a foxtrotter at a vaudeville bash.
This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,qua...This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,quadriceps femoris(vastus medialis and rectus femoris),hamstring/long head of the biceps femoris,gastrocnemius medialis,rectus abdominal,and erector spinae when using the downward breaststroke kick technique.We find that when this sample of swimmers utilized the downward breaststroke kick,max speed and velocity per stroke increased,measured by 12,788 EMG samples,where the results are highly correlated to duration of the aerodynamic buoyant force in breaststroke kick technique.The increases in performance observed from measuring the world class elite swimmers is highly correlated to the duration of the kick aerodynamic buoyant force.Among this sample of elite swimmers,the longer a swimmer demonstrates a buoyant force breaststroke kick,the lower the time in a 100 breaststroke.展开更多
Unusual head trauma is rare with various mechanisms of occurrence. The injuries can be similar to those of road accidents but sometimes with significant complexities. The objective was to determine the frequency of th...Unusual head trauma is rare with various mechanisms of occurrence. The injuries can be similar to those of road accidents but sometimes with significant complexities. The objective was to determine the frequency of this pathology in our practice, describe the different mechanisms and report the craniocerebral lesions caused by this type of trauma. Materials and Method: This was a descriptive study with retrospective collection spread over a period of 3 years. After selecting the files, the patients and/or their companions were contacted by telephone to inquire about them and then returned to the consultation for reassessment. Disease history and information were obtained from patients’ medical records. Result: The frequency of this pathology was 1.78% and his incidence was 0.4 cases per month. The average age of the patients was 13.47 years. All the victims were male. 41.17% of patients were in school. The mechanisms of trauma were the hoof blow 47.1%, the horn blow 29.4% and the stone blow 11.7% respectively. 23.5% of patients were confused and 11.7% children were in coma. One patient presented an anisocoria. The motor deficit was present in 5 cases. CT-scan made it possible to highlight a skull depressing fracture 58.8% and confirm a craniocerebral wound in 35.3%. The average time between patient admission to hospital and completion of surgery was 24.5 hours. The surgery had consisted of the trimming of cranio-cerebral wounds, exploration, duroplasty and lifting of skull depressing fracture. After 15 months of follow-up, the evolution was favorable in 53.3%, the morbidity was 33.4% and the mortality 17.6%. Conclusion: These are rare but serious conditions because they are fatal and disabling. An early and multidisciplinary management can hope to have a good favorable.展开更多
Under the same aerodynamic load,the load transmitted by the kick-reaction link actuator to the aircraft structure is only 1/5 to 1/3 of that of the point-to-point actuator,which can significantly reduce the weight of ...Under the same aerodynamic load,the load transmitted by the kick-reaction link actuator to the aircraft structure is only 1/5 to 1/3 of that of the point-to-point actuator,which can significantly reduce the weight of the structure,and is widely used in the main flight control surface of large and medium-sized civil airliners.In order to restrain the flutter of aircraft rudder surface,it is necessary to design the servo stiffness of the kick-reaction link actuator in the development stage,so that it can meet the dynamic stiffness requirement within the frequency range.Taking the actuator of a civil airliner as the research object,the dynamic stiffness modeling of elevator actuator is carried out on MATLAB platform,and the dynamic stiffness test is carried out to verify the correctness of dynamic stiffness modeling.The simulation and test results show that the actuator can meet the dynamic stiffness design requirements.展开更多
The aim of this study was to investigate the reliability and validity of the New Shooting Accuracy Measurement Software （SAMS）. Thirty two male collegian soccer players performed three inner side kicking to the tran...The aim of this study was to investigate the reliability and validity of the New Shooting Accuracy Measurement Software （SAMS）. Thirty two male collegian soccer players performed three inner side kicking to the transparent goal construction. A High speed camera was placed at the back of the construction to determine where the ball contacted. Recorded video results were assessed with the SAMS and Kinovea software. To investigate test-retest reliability, three kicking results were examined twice by SAMS. Moreover kicking accuracy results obtained with SAMS were compared with results provided by Kinovea in order to investigate validity. Test-retest reproducibility of the new software was excellent, with Concordance Correlation Coefficient for distance to target （0.99, 0.99 and 0.99 respectively） and for angular degree of the ball （0.97, 0.99 and 0.99 respectively）, low Coefficients of Variation （between 2.10 to 6.33 for distance to target and 2.40 to 2.69 for angular degree） and random error （between _.＋ 0.55 to __＋ 3.44 for distance to target and ___ 0.63 to ___ 2.75 for angular degree）. Constant error （between 0.44 to 1.28 for distance to target and -1.16 to __. -2.51 for angular degree） and proportional error （between 0.97 to 0.98 for distance to target and 1.00 to 1.01 for angular degree） were very low for validity. In conclusion, the SAMS represents a valid and reliable instrument to measure accuracy of shooting to target.展开更多
文摘AIM To study the effect of balance intervention program using the "FIFA 11+" program on static and dynamic balance and kicking accuracy of young soccer players.METHODS Twenty young soccer players were allocated to experimental(n = 10) or control(n = 10) groups. The experimental group performed the "FIFA 11+" program three times a week for six weeks. The control group performed their normal warm-up routine. The primary outcomes were measured pre and post intervention, and assessed kicking accuracy, static balance and dynamic balance.RESULTS No differences were found in kicking accuracy following intervention, for both groups, however, static balance improved significantly among the experimental group with significant interaction with the control group, and with high effect size. In addition, the dynamic balance of the left leg of the experimental group, with medium effect size for interaction between groups.CONCLUSION The large effect size of balance improvement that was observed following six weeks of intervention sessions, implies that soccer trainers and coaches should consider the inclusion of "FIFA 11+" as components of programs aimed at improving balance ability/control in young soccer players, as improvement in balance abilities may prevent injuries.
基金supported by the National Funds through FCT,Portuguese Foundation for Science and Technology (UID/DTP/04045/2013)the European Fund for regional development (FEDER) allocated by European Union through the COMPETE 2020 Programme (POCI-01-0145-FEDER006969),Competitiveness and internationalization (POCI)
文摘Purpose:The purpose of this study was to investigate the influence of fatigue upon kicking maximal ball velocity and the target-hitting accuracy of soccer players;and also to examine the effect of the knowledge of the exercise duration upon these 2 parameters.Methods:Twenty-four semi-professional soccer players participated in this study and performed maximal instep kicks before and after the implementation of an exercise protocol,either with or without knowledge of the duration of this protocol.Results:A mixed model of analysis of variance showed that kicking maximal ball velocity was significantly affected(F(5,85)=11.6,p<0.001,η^2=0.39) but only after just 1 circuit of the fatigue protocol and then remained similar.Accuracy did not change during the protocol(F(5,75)=0.23,p=0.76,η^2=0.03) and knowing the duration of exercitation did not affect accuracy and velocity development(F(1,23) ≤1.04,p≥0.32,η~2≤0.06).Conclusion:These findings demonstrated the potential negative effects of fatigue on kicking ball velocity in soccer but not in the kicking accuracy and that the effect of fatigue may not be progressive over time.Knowing or not knowing the duration of exercitation did not affect the results.
基金supported by Portuguese Foundation for Science and Technology (FCT) Grant (SFRH/BD/71470/ 2010) under the Human Potential Operating Programsupported by the European Social Found
文摘Purpose: The aim of this study was to investigate the influence of different exercise intensities induced by a soccer specific protocol on kicking performance in soccer players.Methods: Twelve semi-professional male soccer players participated in this study and performed maximal instep kicks before and after the implementation of an exercise protocol to determine the influence of different intensities upon kicking ball velocity and the target-hitting accuracy.Results: Analysis of variance designs with repeated measures showed that maximal ball velocity was affected only after the most intense circuit(F(6, 66) = 2.3; p = 0.041; η2= 0.18), while accuracy was not affected in the protocol(F(6, 66) = 0.19; p = 0.98; η2= 0.02). Low and moderate intensities did not affect accuracy or kicking ball velocity.Conclusion: These findings suggest that kicking ball velocity is influenced by high-exercise intensities. Low and moderate exercise intensities do not affect the performance of the kick, and intensity does not influence accuracy. Otherwise, it is possible that other mechanisms(not only physiological) may influence players during the exercise.
文摘Kenya builds East Africa’s biggest kungfu academy as Chinese martial arts gain popularity KUNGFU has been a life-long passion for 21-year-old Kamau Mutunga who recently signed up for martial arts classes after a violent attack left him shaken and distressed.
文摘HE＇D been addicted to drugs and alcohol for 22 years, depending daily on doses of cocaine, marijuana and heroin. To survive, Kenyan John Mugenda, 44, resorted to drastic measures.
基金supported by the National Natural Science Foundation of China(Grant No.11475037)the Fundamental Research Funds for the Central Universities(Grant No.DUT19LK38)。
文摘Floquet dynamical quantum phase transitions(DQPTs),which are nonanalytic phenomena recuring periodically in time-periodic driven quantum many-body systems,have been widely studied in recent years.In this article,the Floquet DQPTs in transverse XY spin chains under the modulation ofδ-function periodic kickings are investigated.We analytically solve the system,and by considering the eigenstate as well as the ground state as the initial state of the Floquet dynamics,we study the corresponding multiple Floquet DQPTs emerged in the micromotion with different kicking moments.The rate function of return amplitude,the Pancharatnam geometric phase and the dynamical topological order parameter are calculated,which consistently verify the emergence of Floquet DQPTs in the system.
文摘Known for their vintage-i nspired parties,cabaret-themed revelries and all-aro und debauchery,event compa ny Kick the Gong Around(KTGA)has been kicking the 20s in Shanghai like a foxtrotter at a vaudeville bash.
文摘This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,quadriceps femoris(vastus medialis and rectus femoris),hamstring/long head of the biceps femoris,gastrocnemius medialis,rectus abdominal,and erector spinae when using the downward breaststroke kick technique.We find that when this sample of swimmers utilized the downward breaststroke kick,max speed and velocity per stroke increased,measured by 12,788 EMG samples,where the results are highly correlated to duration of the aerodynamic buoyant force in breaststroke kick technique.The increases in performance observed from measuring the world class elite swimmers is highly correlated to the duration of the kick aerodynamic buoyant force.Among this sample of elite swimmers,the longer a swimmer demonstrates a buoyant force breaststroke kick,the lower the time in a 100 breaststroke.
文摘Unusual head trauma is rare with various mechanisms of occurrence. The injuries can be similar to those of road accidents but sometimes with significant complexities. The objective was to determine the frequency of this pathology in our practice, describe the different mechanisms and report the craniocerebral lesions caused by this type of trauma. Materials and Method: This was a descriptive study with retrospective collection spread over a period of 3 years. After selecting the files, the patients and/or their companions were contacted by telephone to inquire about them and then returned to the consultation for reassessment. Disease history and information were obtained from patients’ medical records. Result: The frequency of this pathology was 1.78% and his incidence was 0.4 cases per month. The average age of the patients was 13.47 years. All the victims were male. 41.17% of patients were in school. The mechanisms of trauma were the hoof blow 47.1%, the horn blow 29.4% and the stone blow 11.7% respectively. 23.5% of patients were confused and 11.7% children were in coma. One patient presented an anisocoria. The motor deficit was present in 5 cases. CT-scan made it possible to highlight a skull depressing fracture 58.8% and confirm a craniocerebral wound in 35.3%. The average time between patient admission to hospital and completion of surgery was 24.5 hours. The surgery had consisted of the trimming of cranio-cerebral wounds, exploration, duroplasty and lifting of skull depressing fracture. After 15 months of follow-up, the evolution was favorable in 53.3%, the morbidity was 33.4% and the mortality 17.6%. Conclusion: These are rare but serious conditions because they are fatal and disabling. An early and multidisciplinary management can hope to have a good favorable.
文摘Under the same aerodynamic load,the load transmitted by the kick-reaction link actuator to the aircraft structure is only 1/5 to 1/3 of that of the point-to-point actuator,which can significantly reduce the weight of the structure,and is widely used in the main flight control surface of large and medium-sized civil airliners.In order to restrain the flutter of aircraft rudder surface,it is necessary to design the servo stiffness of the kick-reaction link actuator in the development stage,so that it can meet the dynamic stiffness requirement within the frequency range.Taking the actuator of a civil airliner as the research object,the dynamic stiffness modeling of elevator actuator is carried out on MATLAB platform,and the dynamic stiffness test is carried out to verify the correctness of dynamic stiffness modeling.The simulation and test results show that the actuator can meet the dynamic stiffness design requirements.
文摘The aim of this study was to investigate the reliability and validity of the New Shooting Accuracy Measurement Software （SAMS）. Thirty two male collegian soccer players performed three inner side kicking to the transparent goal construction. A High speed camera was placed at the back of the construction to determine where the ball contacted. Recorded video results were assessed with the SAMS and Kinovea software. To investigate test-retest reliability, three kicking results were examined twice by SAMS. Moreover kicking accuracy results obtained with SAMS were compared with results provided by Kinovea in order to investigate validity. Test-retest reproducibility of the new software was excellent, with Concordance Correlation Coefficient for distance to target （0.99, 0.99 and 0.99 respectively） and for angular degree of the ball （0.97, 0.99 and 0.99 respectively）, low Coefficients of Variation （between 2.10 to 6.33 for distance to target and 2.40 to 2.69 for angular degree） and random error （between _.＋ 0.55 to __＋ 3.44 for distance to target and ___ 0.63 to ___ 2.75 for angular degree）. Constant error （between 0.44 to 1.28 for distance to target and -1.16 to __. -2.51 for angular degree） and proportional error （between 0.97 to 0.98 for distance to target and 1.00 to 1.01 for angular degree） were very low for validity. In conclusion, the SAMS represents a valid and reliable instrument to measure accuracy of shooting to target.
