Is the perception of intent by association football officials influenced by video playback speed?

Recent research on motion perception indicates that when we view actions in slow-motion, the perceived degree of intent behind those actions can increase. Slow-motion replays are widely used in the checking and review of refereeing decisions by video assistant referees (VAR) in association football. To test whether the decisions of referees are subject to such a bias, 80 elite English professional football officials made decisions about 60 incidents recorded in professional European leagues (recorded as fouls, yellow-card offences or red-card offences by the on-field referee). Both real-time (1×) and slow-motion (0.25×) playback speeds were used. Participants had no prior knowledge of the incidents, playback speeds or disciplinary sanctions relating to each clip. Three judgements were made about each incident: extent of contact, degree of intent, and disciplinary sanction. Results showed an effect of playback speed on decision-making, but not a consistent bias due to slow-motion. Instead the distinction between yellow-card and red-card offences was clearer: Under slow-motion, yellow-card incidents were judged as less severe, and red-card incidents are judged as more severe, thus enhancing the distinction between these offences. These results are inconsistent with previous scientific reports that perceived intent is heightened by slow video playback speed.

Changes in a top-level soccer referee's training, match activities, and physiology over an 8-year period: a case study.

Athlete case studies have often focused on the training outcome and not the training process. Consequently, there is a dearth of information detailing longitudinal training protocols, yet it is the combined assessment of both outcome and process that enhances the interpretation of physical test data. We were provided with a unique opportunity to assess the training load, physical match performance, and physiological fitness of an elite soccer referee from the referee's final season before attaining full-time, professional status (2002) until the season when he refereed the 2010 UEFA Champions League and FIFA World Cup finals. An increased focus on on-field speed and gym-based strength training was observed toward the end of the study period and longitudinal match data showed a tendency for decreased total distances but an increased intensity of movements. Laboratory assessments demonstrated that VO2max remained stable (52.3 vs 50.8 mL·kg-1·min-1), whereas running speed at the lactate threshold (14.0 vs 12.0 km·h-1) and running economy (37.3 vs 43.4 mL·kg-1·min-1) both improved in 2010 compared with 2002.

Ageing and physical match performance in English Premier League soccer referees.

Soccer referees are required to keep up with play at all times despite occupying an age bracket of on average 10-15 years older than their playing counterparts. Therefore, the aim of the present study was to examine the effect of age upon the physical match performances and match physiological loads of elite-level soccer referees. Match analysis data was collected (Prozone((R)), Leeds, UK) from 22 professional soccer referees (age range 31-48 years) on FA Premier League matches over four consecutive seasons (778 observations). Physical match performance categories were total-distance covered (TD); high intensity running distance (speed >5.5 ms(-1), HIR); sprint count (>7.0 ms(-1), SC); top sprinting speed (TS); average distance from the ball (DB) and average distance from fouls (DF). Significant age effects were found for TD (r=-0.52, p<0.001), HIR (r=-0.53, p<0.001) and SC (r=-0.53, p<0.001). No age effect was found for DB and DF (p>0.05). Despite covering less TD, HIR and performing fewer sprints the older referees (43-48 years) were able to maintain an average distance from fouls that was comparable to that recorded by the young (31-36 years) referees. Therefore, the reduced physical match performances associated with increasing referee age did not appear to impact upon the older referees' ability to keep up with play. In light of these findings, refereeing governing bodies may wish to review their age-based retirement guidelines.

Effects of creatine supplementation on cerebral white matter in competitive sportsmen.

OBJECTIVES: To determine the neurobiochemical sequelae of oral creatine monohydrate supplementation in active athletes. DESIGN/PARTICIPANTS: Eighteen sportsmen underwent single-voxel proton magnetic resonance spectroscopy of the deep frontal cerebral white matter before and after 5 days of oral ingestion: 12 of 18 swallowed 4 x 5 g creatine monohydrate per day, and the remaining swallowed a placebo. MAIN OUTCOME MEASUREMENTS: Creatine, choline, and N-acetyl spectral resonances were evaluated at both long (135 ms) and short (20 ms) echo times. RESULTS: A mixed-design factorial ANOVA demonstrated no interaction over time in any of the measures (P at least 0.081). CONCLUSIONS: The results suggest that, for the given dosage regimen, ingested creatine augmentation does not alter the magnetic resonance visible creatine pool in the deep frontal cerebral white matter of young active sportsmen.