title: Sports teams as complex adaptive systems: manipulating player numbers shapes behaviours during football small-sided games.
abstract: Small-sided and conditioned games (SSCGs) in sport have been modelled as complex adaptive systems. Research has shown that the relative space per player (RSP) formulated in SSCGs can impact on emergent tactical behaviours. In this study we adopted a systems orientation to analyse how different RSP values, obtained through manipulations of player numbers, influenced four measures of interpersonal coordination observed during performance in SSCGs. For this purpose we calculated positional data (GPS 15 Hz) from ten U-15 football players performing in three SSCGs varying in player numbers (3v3, 4v4 and 5v5). Key measures of SSCG system behaviours included values of (1) players' dispersion, (2) teams' separateness, (3) coupling strength and time delays between participants' emerging movements, respectively. Results showed that values of participants' dispersion increased, but the teams' separateness remained identical across treatments. Coupling strength and time delay also showed consistent values across SSCGs. These results exemplified how complex adaptive systems, like football teams, can harness inherent degeneracy to maintain similar team spatial-temporal relations with opponents through changes in inter-individual coordination modes (i.e., players' dispersion). The results imply that different team behaviours might emerge at different ratios of field dimension/player numbers. Therefore, sport pedagogists should carefully evaluate the effects of changing RSP in SSCGs as a way of promoting increased or decreased pressure on players.
authors.affiliation: FC Zenit, St. Petersburg, Russia ; Centre for Research, Education, Innovation and Intervention in Sport (CIFI2D), Faculty of Sport, Universidade do Porto, Rua Dr. Plácido Costa, 91, 4200-450 Porto, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Silva
authors.affiliation: Escola de Turismo, Desporto e Hospitalidade, Universidade Europeia, Lisboa, Portugal ; CIPER, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada Dafundo, Portugal.
authors.forename: Luís
authors.initials: L
authors.lastname: Vilar
authors.affiliation: Centre for Sports Engineering Research, Sheffield Hallam University, Sheffield, UK ; FidiPro Programme, University of Jyväskylä, Jyväskylä, Finland.
authors.forename: Keith
authors.initials: K
authors.lastname: Davids
authors.affiliation: CIPER, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada Dafundo, Portugal.
authors.forename: Duarte
authors.initials: D
authors.lastname: Araújo
authors.affiliation: Centre for Research, Education, Innovation and Intervention in Sport (CIFI2D), Faculty of Sport, Universidade do Porto, Rua Dr. Plácido Costa, 91, 4200-450 Porto, Portugal.
authors.forename: Júlio
authors.initials: J
authors.lastname: Garganta
keywords: Degeneracy; Emergent behaviours; Relative space per player; Small-sided and conditioned games; Team games as complex adaptive systems