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.

Exercise protocol that simulated the demands of a match while responding to filmed sequences of offensive play. HR, blood lactate concentrations, anticipation performance, visual search behaviors, and immediate retrospective verbal reports were assessed. Results High-level players demonstrated superior anticipation compared with low-level counterparts, but both groups showed reduced accuracy across the exercise protocol. Mean HR and blood lactate values increased significantly from the beginning to the end of each half of the match (P < 0.05). Visual search data revealed significant group–test session interactions for the number of locations (P < 0.0001), mean fixation durations (P = 0.003), and number of fixations (P < 0.0001). When compared with low-level participants, high-level players used more fixations of shorter duration to more locations at the beginning of each half; whereas at the end of the exercise protocol, they used fewer fixations of longer duration to a lower number of locations. There was a significant group–type of statement–test session interaction (P = 0.001) for the verbal report data. High-level participants generated a great number of evaluation, prediction (in the beginning of the second half), and deep planning statements (during the first and the last test sessions). In contrast, low-level players used more superficial cognition statements than high-level individuals in both halves. Conclusion The intermittent exercise induced changes in perceptual-cognitive processes in both groups, although high-level players exhibited superior anticipation across test sessions accompanied by more effective search behaviors and elaborate thought processes....

System of tactical assessment in Soccer (FUT-SAT): Development and preliminary validation