Nic James

The influence of match location, quality of opposition, and match status on technical performance in professional association football

Abstract The aim of this study was to examine the effects of match location, quality of opposition, and match status on the technical aspects of performance within a single professional British football team. Forty matches from the 2002–2003 and 2003–2004 domestic league seasons were notated post-event using a computerized notational analysis system with 13 on-the-ball behaviours and corresponding outcomes (successful or unsuccessful) assessed. Log-linear modelling procedures indicated that the incidences of all on-the-ball technical behaviours, with the exception of “set-pieces”, were influenced by at least one of the three situation variables, with both independent and interactive effects found. In contrast, logit modelling suggested that there was no general influence of the situation variables on the outcomes of the on-the-ball behaviours. The findings emphasize the need for notational analysts and coaches to consider the potential independent and interactive effects of match location, quality of opposition, and match status when assessing the technical components of football performance, particularly those relating to behaviour occurrence. Future research should consider the effects of additional situation variables purported to influence the mental, physical, technical, and tactical components of football performance.

Age-related decrease in physical activity and functional fitness among elderly men and women.

Aim To determine differences in physical activity level and functional fitness between young elderly (60–69 years) and old elderly (70–80 years) people with the hypothesis that an age-related decline would be found. Methods A total of 1288 participants’ level of physical activity was evaluated using the International Physical Activity Questionnaire: 594 were male (mean ± standard deviation: body height 175.62 ± 9.78 cm; body weight 82.26 ± 31.33 kg) and 694 female (mean ± standard deviation: body height 165.17 ± 23.12 cm; body weight 69.74 ± 12.44 kg). Functional fitness was also estimated using the Senior Fitness Test: back scratch, chair sit and reach, 8-foot up and go, chair stand up for 30 seconds, arm curl, and 2-minute step test. Results Significant differences (P < 0.05) were found for all Senior Fitness tests between young elderly (60–69 years) and old elderly (70–80) men. Similar results were found for the women, except no significant differences were found for the chair sit and reach and the 2-minute step test. From the viewpoint of energy consumption estimated by the International Physical Activity Questionnaire, moderate physical activity is dominant. In addition, with aging, among men and women older than 60 years, the value of the Metabolic Equivalent of Task in total physical activity significantly reduces (P < 0.05). Conclusions This study found that the reduction in physical activity level and functional fitness was equal for both men and women and was due to the aging process. These differences between young and old elderly people were due to the reduction of muscle strength in both upper and lower limbs and changes in body-fat percentage, flexibility, agility, and endurance.

Possession as a performance indicator in soccer.

In soccer, the ability to retain possession of the ball for prolonged periods of time has been linked to success (Hook and Hughes, 2001). The accuracy of this assertion was investigated by comparing 24 matches involving successful and unsuccessful English premier league teams within the 2001-2002 season. Specifically the teams’ possessions were analysed depending on evolving match status i.e. whether the team was winning, losing or drawing. All possessions less than 3 seconds in duration were removed from the data as they were not deemed to include significant events pertaining to a teams’ strategy. Successful teams were found to have significantly longer possessions than unsuccessful teams irrespective of match status i.e.winning (p<0.01), losing (p<0.05) and drawing (p<0.01). However both successful and unsuccessful teams had longer durations of possession when they were losing matches compared to when winning. It was concluded that within elite English football possession is related to successful performance but it is likely this is down to differences in individual player’s skill levels rather than specific team strategy.

Relationship between Repeated Sprint Ability and Aerobic Capacity in Professional Soccer Players

Aim. The aim of the present study was to investigate the relationship between maximal aerobic capacity (VO2 max) and repeated sprint ability (RSA) in a group of professional soccer players. Methods. Forty-one professional soccer players (age 23 ± 4 yrs, height 180.0 ± 5.3 cm, weight 79.6 ± 5.3 kg) were required to perform tests to assess RSA and VO2 max on two separate days with at least 48 hr rest between testing sessions. Each player performed a treadmill test to determine their VO2 max and a test for RSA involving the players completing 6 × 40 m sprints (turn after 20 m) with 20 s active recovery between each sprint. Results. There was a significant negative correlation between body mass normalised VO2 max and mean sprint time (RSAmean) (r = −0.655; P < 0.01) and total sprint time (RSAtotal) (r = −0.591, P < 0.01). Conclusion. Results of the current study indicate that VO2 max is one important factor aiding soccer players in the recovery from repeated sprint type activities.

The development of position-specific performance indicators in professional rugby union

The aim of this study was to construct a valid and reliable methodology for the analysis of performance profiles of individual playing positions within rugby union. Twenty-two matches were sampled from the domestic season of a professional male rugby union team. Key performance indicators for individual positions were developed and notated using a computerized behavioural analysis system. Performance profiles of playing positions containing data from one or more individuals were then constructed to compare intra-positional differences. Significant differences (chi-square) were observed between individuals within all the tested playing positions for the principal performance indicators (passing, carrying and tackling for the forward positions, and passing, carrying, tackling and kicking for the backs). For example, the difference between the two outside-halves in the study (P < 0.001) was illustrated by one of the players having a median of 6 successful carries for the season (95% confidence limits of 13 and 3), whereas the other had a median of 2 successful carries (95% confidence limits of 5 and 1). The findings suggest that while general positional performance profiles appear to exist, intra-positional differences may occur due to variations in an individuals style of play, the decision-making demands of the position and the effects of potential confounding variables. Multiple profiles may therefore be necessary for some playing positions to account for variation in factors such as playing conditions and the strength of the opposition.

Game location effects in professional soccer: a case study.

Game location effects (home versus away) upon technical and tactics-related behaviours were investigated in a professional English soccer team. Matches (n=30) from the 2004-05 domestic season of a top five side from the English Premiership league were notated post-event via a computerized system and compared as a function of game location using non-parametric analysis procedures. An overall home advantage was found for the sample in relation to home-winning and home-goal percentage. For technical performance the team exhibited more successful behaviours, such as tackles, passes and aerial challenges, at home than away. For tactics-related behaviours, more aerial challenges, corner kicks, crosses, passes, dribbles and shots on goal were performed at home in the attacking third of the pitch. In addition, more goal kicks, interceptions, aerial challenges and clearances were performed in the defensive third when playing away. These findings suggest that game location effects may exist at a strategic level within individual teams. Future research should consider the influence of other confounding variables such as weather conditions, game status, team form and opposition quality.

Team performance indicators as a function of winning and losing in rugby union.

The construction of a valid and reliable methodology for the analysis of team performance indicators within rugby union is presented. Twenty matches were sampled from the domestic season of a professional male rugby union team and notated using a computerised behavioural analysis system. A comprehensive list of twenty-two team performance indicators were developed via expert coaches and analysts. Examination of each indicator using Mann-Whitney U analysis revealed statistical differences between winning and losing performances for only two of the identified team indicators (lineouts won on oppositions throw and tries scored). Practical differences were visible within other indicators including increases in the percentage of turnovers won (mdn= 71.88, 95% confidence limits= 88.89 and 33.33 when winning, and mdn= 47.25, 95% confidence limits= 72.22 and 30 when losing). The findings highlight a number of team factors which contribute to winning matches. Subsequent combination of these variables may be used to develop a model to predict future performance within rugby union.

Analysis of strategies in soccer as a function of European and domestic competition

Existing investigations of strategies in soccer using notational analysis have traditionally focused upon nomothetic analysis of international competitions such as World or European Championships (i.e., Luhtanen et al., 2001; Yamanaka, et al., 2001). To enhance the applied benefit of notational analysis idiographic assessment of teams, strategies are required to establish meaningful normative profiles (Hughes et al., 2001). A need also exists to examine individual player behaviours to determine potential influences upon team strategies. The aim of the current study was to assess the strategies of a team in both domestic and European competition over a competitive season. Matches of a British professional soccer team were analysed using a computerised behavioural measurement package with regard to frequency and duration of possession in designated areas of the soccer field. European matches were characterised by more play in pre-defensive areas at the expense of pre-offensive areas compared to domestic matches. Attacking play was found to occur more frequently down the right hand side of the pitch in domestic compared to Europe. Variability was also observed between ball possession and passing difficulty made by individual players in each pitch area. The findings suggest that differences in tactical strategies are evident at both individual and team levels as a function of the nature of the competition. Individual roles therefore appear to be dictated by playing position, team tactics and game circumstances.

Observational assessment of situation awareness, team differences and training implications.

The two goals were to investigate, first, the practicability and reliability of observational assessment of team situation awareness (SA) and, second, the nature of any team differences, their consistency and training implications. Five shift teams tackled three scenarios, each with three probe events concerning SA, and three observers viewed and rated concurrently each shift. This methodology was found to be practicable and achieved satisfactory rater reliability as indicated by intraclass and inter-rater correlations. Team differences in SA emerged although there was no consistent pattern. A retrospective analysis of individual and team behaviours relating to SA was performed using the Critical Incident Technique. A total of 75 incidents and 20 behavioural dimensions relevant to SA were identified and these were subsumed under planning, problem solving, team coordination, attention, communication and knowledge. These findings are discussed with regard to the nature and measurement of SA, and the content of training to improve SA for control room teams.

Reliability procedures for categorical data in performance analysis.

A number of papers have discussed reliability assessment techniques but none have previously limited themselves to methods appropriate to the collection of categorical data on the nominal scale i.e. where events are recorded within defined categories, as in many instances for performance analysis. This paper makes a number of recommendations including the use of a gold standard coding to compare the typical analyst’s codes against. Reliability measures should reflect the way in which the notation data is analysed so that assessments can be made regarding the extent to which each variable presented in the results was coded accurately. The Yule’s Q statistic, based on the odds ratio, is recommended as the reliability statistic of choice for categorical data due to the intuitiveness of the measure, its ease of calculation and its apparent applicability to the decision making of performance analysts. Furthermore a value of 0.95 or above should be deemed an acceptable value to determine confidence in the analyst’s ability to place an event into a category reliably.