Performance analysis: advantages and limitations

Both advantages and limitations exist in relation to the skill-focussed

performance analysis used in this thesis. Performance analysis was beneficial because it allowed a profile of handball use in games to be developed, which included execution, environment and outcome factors. The profile of handball was then used to help guide the testing procedures. Specifically, execution factors including the length (0-6 m), direction (forward), pre-execution motion (stationary) were chosen for biomechanical assessment as these were the most prevalent features of in-game handball execution (Parrington et al., 2013b [Chapter 2 of this thesis]). Although performance analysis was used to guide research methods in this thesis, this type of process also has high potential to be used to assist coaching staff in the planning of training sessions.

Secondly, the skill-focussed performance analysis was advantageous because of the ability to derive additional contextual information of what factors influenced the

success of the pass. This methodological approach was solid because the interaction of skill and successful play is believed to be an important contribution to the successful outcome of games (Bartlett, 2001). Publically available statistics only include basic counts of skill executions and outcomes. For example, the National Rugby League (NRL) provides information about the number of tries, tackles and run metres (NRL statistics, 2014), while for AFL, statistics provided include number of disposals, overall disposal efficiency, marks and tackles (Australian Football League, 2013b). In

comparison, more detailed statistics providers employed by clubs produce a greater range of statistics than these websites such as a stratification of kicking and handballing efficiency (Champion Data, 2012). Nevertheless, there are still limited statistics

provided on technical, decision making and environmental factors that may influence the overall performance of a player, especially in relation to a specific skill such as handballing.

Performance analysis conducted in this thesis was able to provide additional contextual information on performance, such as which factors related to the occurrence of effective and ineffective passes. This is of particular benefit, from both a research and applied coaching perspective, because it allows critical factors to be highlighted, confirmed or challenged. For example, in consultation with coaching staff, players ‘squaring up’ when handballing was discussed as an important factor underlying

handballing success. The findings from Study 1 indicate that efficiency was 21% higher when players were square to their target when passing. Furthermore, the results provide evidence that help to validate ‘squaring up’ as a factor of handballing performance. As a result of this finding, the motion and position of the lower and upper trunk were

Thirdly, contextual information from performance analysis is beneficial because it provides the ability to look at how different aspects of performance interrelate. That is, skill-focussed performance analysis allows one or more factors to be analysed in combinations to observe any influence and help aid the interpretation of data. For example, data from Parrington et al. (2013b [Chapter 2 of this thesis]) demonstrated that passes made from a non-squared stance occurred under greater levels of high and

moderate pressure, which can assist interpretation of why these passes were less

efficient, as increased pressure negatively influenced efficiency. Moreover, this level of detailed information allows coaches and researchers to measure a specific parameter against other factors (e.g. pressure) in order to understand more about game events.

Finally, performance analysis is advantageous because of the ability to be conducted without the use of expensive equipment. The evaluation of in-game handball use was conducted on readily available game footage from the 2008 and 2009 AFL seasons. This is an advantage to anyone wishing to conduct this style of analysis, as most teams, regardless of skill level, have access to a video camera and basic computer software.

A limitation of this method was the time required for the data collection. Due to the data being manually recorded and the high number of skill executions per game, skill-focussed performance analysis was very time consuming. At least two to three replays of each handball was often required in order to tease out each of the parameters collected in the analysis conducted in Study 1 (Chapter 2).

Performance analysis is a valid and reliable technique, but it is not able to collect the same scale of technical information as biomechanical analysis. For example, due to continuously changing camera perspectives used in live footage, actual distance of handballs could not be measured using performance analysis. As a result, handball

distance was categorised in a binary and qualitative fashion, as either short or long, rather than a quantitative value. Although acknowledged here as a possible limitation, it was not considered an issue in this thesis.

In addition, performance analysis is unable to provide information on underlying mechanisms and processes that underpin the outcome (Glazier, 2010). Understanding this limitation, this thesis used the skill-focussed analysis to identify the profile of skill executions in addition to linking parameters to handball performance (% Efficiency). The analysis was aimed at assessing the influence of technical, decision-making and pre-execution factors (leading up to the handball), rather than determining the underlying mechanisms. Thus, despite the limitations identified, the utility of this methodology outweighed the potential drawbacks.