Timescales for exploratory tactical behaviour in football small-sided games

The aim of this study was to identify the dynamics of tactical behaviour emerging on different timescales in football small-sided games and to quantify short- and long-term exploratory behaviour according to the number of opponents. Two teams of four professional male footballers played small-sided games against two different teams with a variable number of opponents (3, 5 and 7). Data were collected using a combination of systematic observation and a non-differential global positioning system (15 Hz). The temporal diversity and structural flexibility of the players were determined by calculating the dynamic overlap order parameter q, entropy and trapping strength. Analysis of the exploratory dynamics revealed two different timescales, forming a different metastable landscape of action for each constraint. Fast dynamics lasted on average a few seconds and consisted of changes in tactical patterns. The long timescale corresponded to the shared tasks of offence and defence lasting tens of seconds. The players’ tactical diversity decreased with an increasing number of opponents, especially in defence. Manipulating numerical imbalance is likely to promote changes in the diversity, unpredictability and flexibility of tactical solutions. The fact that the temporally nested structure of constraints shaped the emergence of tactical behaviour provides a new rationale for practice task design. The manipulation of numerical imbalance on the timescale of a few tens of seconds, on which the exploratory behaviour of players saturates, may help coaches to optimise the exploratory efficiency of the small-sided games.     

Schools as knowledge work organizations: Perspectives and implications from the new management literature

The authors argue that the knowledge work metaphor is the most powerful image of schools for understanding reform. Using themes from the new management literature, such as shared decision making, collegiality, innovation, and experimentation, as additional guides for school improvement, the authors develop a case for systemic reform based on the professionalization of teaching and the integration of theory, research, and practice, Finally, transformational leadership is presented as the key to facilitating systemic reform.     

The Academic Rational Beliefs Scale: Development,Validation, and Implications for College Counselors

This study reports on a new instrument, the Academic Rational Beliefs Scale, designed to measure college students' academic beliefs along a rational‐irrational continuum. The new instrument is potentially useful when working with students experiencing academic difficulties. Information about test construction, reliability, validity, and generalizability are presented and implications, benefits, and cautions associated with use of the instrument as a college counseling tool are discussed.     

Visual Attention Preference for Intermediate Predictability in Young Children

How do children allocate their attention? There is too much information in the world to encode it all, so children must pick and choose. How do they organize their sampling to make the most of the learning opportunities that surround them? Previous work shows infants actively seek intermediately predictable information. Here we employ eye-tracking and computational modeling to examine the impact of stimulus predictability across early childhood (ages 3–6 years, n = 72, predominantly Non-Hispanic White, middle- to upper-middle-income), by chronological age and cognitive ability. Results indicated that children prefer attending to stimuli of intermediate predictability, with no differences in this pattern based on age or cognitive ability. The consistency may suggest a robust general information-processing mechanism that operates across the lifespan.     

Acute neuromuscular and performance responses to Nordic hamstring exercises completed before or after football training

ABSTRACT

The optimal scheduling of Nordic Hamstring exercises (NHEs) relative to football training sessions is unknown. We examined the acute neuromuscular and performance responses to NHE undertaken either before (BT) or after (AT) simulated football training. Twelve amateur players performed six sets of five repetitions of the NHE either before or after 60 min of standardised football-specific exercise (SAFT⁶⁰). Surface electromyography signals (EMG) of the hamstring muscles were recorded during both the NHE, and maximum eccentric actions of the knee flexors (0.52 rad · s^–1) performed before and after the NHE programme, and at 15 min intervals during SAFT⁶⁰. Ten-metre sprint times were recorded on three occasions during each 15 min SAFT⁶⁰ segment. Greater eccentric hamstring fatigue following the NHE programme was observed in BT versus AT (19.8 %; very likely small effect), which was particularly apparent in the latter range of knee flexion (0–15°; 39.6%; likely moderate effect), and synonymous with hamstring EMG declines (likely small–likely moderate effects). Performing NHE BT attenuated sprint performance declines (2.0–3.2%; likely small effects), but decreased eccentric hamstring peak torque (–14.1 to –18.9%; likely small effects) during football-specific exercise. Performing NHE prior to football training reduces eccentric hamstring strength and may exacerbate hamstring injury risk.