Background:The side effects of the FIFA 11+program on performance have not been generally reviewed.The objective of this study was to synthesize the literature on the effects of the 11+on players’performance.Methods:...Background:The side effects of the FIFA 11+program on performance have not been generally reviewed.The objective of this study was to synthesize the literature on the effects of the 11+on players’performance.Methods:Five online databases(PubMed,Scopus,ScienceDirect,Springer,and Google Scholar)were searched(from April 2006 to March 2022)using predefined keywords and sub-keywords.The potential references were primarily recorded through Endnote and imported to Covidence.Out of the 123 references screened by 2 blinded researchers through the software,59 full texts were assessed for eligibility,33 of which were ultimately included.The quality of the studies and the risk of bias were then assessed.Study ID,title,place,aim,design,start/end dates,population description,study criteria,statistical analysis,and outcomes were extracted.Results:Studies were conducted on male and female players aged 10-32 years old.The quality of the studies was moderate to high,and except for unclear bias for blinding outcome assessment,the risk of bias for all domains was low.Long-term application of the 11+improved most biomechanical measures and physiological responses except for lower extremity stability,ankle evertors time latency,ankle dorsiflexion,and proprioception.Conversely,the 11+showed acute negative effects on physical performance compared to dynamic warm-ups and non-significant effects on technical abilities.Conclusion:Mid-to-long-term implementation of the 11+improved the maj ority of biomechanical and a couple of physical measure s but showed no effects on technical skills.Precaution must be observed for using the 11+before competitions,as it could acutely decrease physical/technical performance.Given the contradictory nature of the literature,further studies should evaluate the short-to-mid-term effects of the 11+.Further studies are required to address ankle responses to the 11+intervention.展开更多
In relay-assisted cooperative communication,relay nodes help forwarding the information of a source node in case of link failure between the source and a destination.Although user cooperation improves the overall effi...In relay-assisted cooperative communication,relay nodes help forwarding the information of a source node in case of link failure between the source and a destination.Although user cooperation improves the overall efficiency of the network,it requires incentive to stimulate potential relay nodes to assist the source by forwarding its data to the destination.Moreover,the potential relays are better informed than the source about their channel conditions to destination,which results in asymmetric information between the source and the relays.In this paper,we study the problem of lack of forwarding incentive in cooperative communication when channel state information of relays is private information and not known by the source.To tackle this problem,we apply the principle of contract theory to a cooperative wireless system.Source first designs incentive compatible and individually rational contract,consisting of a set of power-credit pairs.Then it broadcasts contract items to nearby nodes.Once the source node receives reply messages from the volunteer relays,it chooses one or more relays based on its requirements and communication starts.Simulation results show how credit assignment works in order to stimulate relays to cooperate and prevents relays from cheating behavior.展开更多
文摘Background:The side effects of the FIFA 11+program on performance have not been generally reviewed.The objective of this study was to synthesize the literature on the effects of the 11+on players’performance.Methods:Five online databases(PubMed,Scopus,ScienceDirect,Springer,and Google Scholar)were searched(from April 2006 to March 2022)using predefined keywords and sub-keywords.The potential references were primarily recorded through Endnote and imported to Covidence.Out of the 123 references screened by 2 blinded researchers through the software,59 full texts were assessed for eligibility,33 of which were ultimately included.The quality of the studies and the risk of bias were then assessed.Study ID,title,place,aim,design,start/end dates,population description,study criteria,statistical analysis,and outcomes were extracted.Results:Studies were conducted on male and female players aged 10-32 years old.The quality of the studies was moderate to high,and except for unclear bias for blinding outcome assessment,the risk of bias for all domains was low.Long-term application of the 11+improved most biomechanical measures and physiological responses except for lower extremity stability,ankle evertors time latency,ankle dorsiflexion,and proprioception.Conversely,the 11+showed acute negative effects on physical performance compared to dynamic warm-ups and non-significant effects on technical abilities.Conclusion:Mid-to-long-term implementation of the 11+improved the maj ority of biomechanical and a couple of physical measure s but showed no effects on technical skills.Precaution must be observed for using the 11+before competitions,as it could acutely decrease physical/technical performance.Given the contradictory nature of the literature,further studies should evaluate the short-to-mid-term effects of the 11+.Further studies are required to address ankle responses to the 11+intervention.
文摘In relay-assisted cooperative communication,relay nodes help forwarding the information of a source node in case of link failure between the source and a destination.Although user cooperation improves the overall efficiency of the network,it requires incentive to stimulate potential relay nodes to assist the source by forwarding its data to the destination.Moreover,the potential relays are better informed than the source about their channel conditions to destination,which results in asymmetric information between the source and the relays.In this paper,we study the problem of lack of forwarding incentive in cooperative communication when channel state information of relays is private information and not known by the source.To tackle this problem,we apply the principle of contract theory to a cooperative wireless system.Source first designs incentive compatible and individually rational contract,consisting of a set of power-credit pairs.Then it broadcasts contract items to nearby nodes.Once the source node receives reply messages from the volunteer relays,it chooses one or more relays based on its requirements and communication starts.Simulation results show how credit assignment works in order to stimulate relays to cooperate and prevents relays from cheating behavior.
