Sub-elite Australian Football Players Research Articles

Methods of performance analysis in women's Australian football: a scoping review.

The first women's Australian football (AF) professional competition was established in 2017, resulting in advancement in performance analysis capabilities within the sport. Given the specific constraints of women's AF, it is currently unclear what match-play performance analysis methods and techniques are implemented. Therefore, the aim of this scoping review was to describe and critically appraise physical, technical, and tactical performance analysis methods that have been employed in women's and girls' AF match-play. A systematic search was conducted on the 27th of June 2022 through five databases. Eligibility criteria were derived from the PCC framework with the population (P) of women and girls AF players, of any level of play; concepts (C) of interest which were measures, data, and methods related to the sport's physical, technical, and tactical performance; and the context (C) of methods that analysed any match-play performance. A narrative synthesis was conducted using extracted study characteristic data such as sample size, population, time period, collection standards, evaluation metrics for results, and application of thematic categorisations of previous sports performance reviews. Critical appraisal of eligible studies' methodologies was conducted to investigate research quality and identify methodological issues. From 183 studies screened, twelve eligible studies were included, which examined match-play through physical (9/12, 75%), technical (4/12, 33%), and tactical analysis (2/12, 17%). Running demands and game actions analysis were the most researched in senior women's AF. Research into junior girls' AF match-play performance has not been investigated. No research has been conducted on non-running physical demands, contact demands, acceleration, and tactical aspects of women's AF. All studies utilised either inferential statistics or basic predictive models. Critical appraisal deemed most studies as low risk of bias (11/12, 92%), with the remaining study having satisfactory risk. Future research utilising increased longitudinal and greater contextual data is needed to combat the prominent issue of data representativeness to better characterise performance within women's and girls' AF. Additionally, research involving junior and sub-elite AF players across the talent pathways is important to conduct, as it provides greater context and insight regarding development to support the evolving elite women's AF competition. Women's AF has been constrained by its resource environment. As such, suggestions are provided for better utilisation of existing data, as well as for the creation of new data for appropriate future research. Greater data generation enables the use of detailed machine learning predictions, neural networks, and network analysis to better represent the intertwined nature of match-play performance from technical, physical, and tactical data.

Biomechanics of accurate and inaccurate goal-kicking in Australian football: Group-based analysis.

Goal-kicking is an important skill in Australian Football (AF). This study examined whether kinematic differences exist between accurate and inaccurate goal-kicks and determined the relationships between technical factors and accuracy. Eighteen elite to sub-elite AF players performed 15 x 30 m goal-kicks on an AF training ground, with three-dimensional kinematics collected using the Xsens inertial measurement system (Xsens Technologies B.V., Enschede, the Netherlands). A general linear mixed modelling approach and regression-based statistics were employed to quantify differences between accurate and inaccurate goal kicks and the relationships between technical factors and accuracy. Accurate goal-kicks were characterised by a straighter approach line, with less kick-leg joint range of motion (knee and hip), lower linear velocity (centre of mass, foot speed), angular velocity (knee and shank), and less support-leg knee flexion during the kicking phase compared to inaccurate goal-kicks. At the end of the follow through, players produced greater ankle plantarflexion and a straighter-leg line in accurate goal-kicks. Findings in this research indicated that many factors interact with goal-kicking accuracy in AF, ranging from the players’ approach line path, their support-leg mechanics, the kick-leg swing motion, to the final position of the kicker during their follow through.

Nutritional Intake in Australian Football Players: Sports Nutrition Knowledge and Macronutrient and Micronutrient Intake.

This study compared the energy, macronutrient, and micronutrient intake in elite and sub-elite Australian football players and compared nutritional intake to current recommendations. Sports nutrition knowledge was also quantified and compared between elite and sub-elite players. Nutritional intake was quantified in elite (n = 35) and sub-elite (n = 31) players using the Automated Self-Administered 24-Hour Dietary Assessment Tool. The 88-item Sports Nutrition Knowledge Questionnaire was used to quantify knowledge related to general nutrition concepts, fluid, recovery, weight control, and supplements. Elite players had a higher nutritional intake (mean ± SD) for energy (14,140 ± 5,887kJ [elite players] vs 10,412 ± 3,316kJ [sub-elite players]; P = .002) and fat (40% ± 6% [elite players] vs 34% ± 6% [sub-elite players]; P < .001). Protein intake exceeded the recommended intake in 77% of elite players and 68% of sub-elite players, and carbohydrate intake was below the recommended intake for 91% of elite players and 97% of sub-elite players. Sodium intake recommendations were exceeded by 100% of elite and sub-elite players. Both elite and sub-elite players answered 51% of the Sports Nutrition Knowledge Questionnaire questions correctly. The percentage of correctly answered questions specific to supplements was 27% for elite players and 18% for sub-elite players. The results of the current investigation suggest that Australian football players' nutritional intake is inconsistent with current recommendations for macronutrients and some micronutrients. Furthermore, players may benefit from additional knowledge of the risks and benefits of supplement use.

Genetic predictors of match performance in sub-elite Australian football players: A pilot study

Background/ObjectiveThe current study aimed to determine whether previously identified candidate polymorphisms were associated with match performance in sub-elite Australian Rules Football (ARF) players. MethodsThe genotypes of thirty players were analysed along with 3x1-kilometre time trial results, ARF-specific skill assessments (handball and kicking), and match performance (direct game involvements) per minute (DGIs/min) to investigate if there was a relationship between any of the variables. ResultsResults support previous findings that aerobic time trials are a significant predictor of DGIs/min in sub-elite ARF players. Significant associations were found for genotypes ADRB2 CC (p = .001), PPARGC1A AA (p = .001), PPARGC1A AG (p < .001), ACE ID (p < .001), COMT AA (p = .003), BDNF AG (p = .008), ADRB1 CC (p = .018) and ADRB3 CC (p = .010) and the 3x1-kilometre time trials (p < .001). In the current study, a variant in the DRD2 gene was a strong predictor of handball possessions during a match. Significance was seen for variants in the BDNF and COMT genes when the kicking and handball skill test results were combined and used in a linear mixed model to predict DGIs/min, suggesting a potential relationship with motor learning. ConclusionsThe confirmation of genetic predictors of player performance in a team sport, such as ARF, suggests a portion of the physiological mechanisms of skill and ARF-specific talent may be explained by the expression of a specific number of genes.

Identification of genetic markers for skill and athleticism in sub-elite Australian football players: a pilot study.

Natural genetic variation contributes towards athletic performance in various strength/power and endurance based sports. To date, no studies have explored the genetic predisposition towards skill and athletic performance in Australian Football (AF) players. The present pilot study recruited 30 sub-elite AF players who completed tests of endurance, power and technical skill. Specific polymorphisms in nine genes were screened, and assessed for a possible association with athletic and skill traits. Statistical analysis using generalized linear models identified a number of polymorphisms predictive of endurance and technical skill. The angiotensin-converting enzyme (ACE), normally responsible for regulation of body fluid volume, was a significant factor in predicting 'all round' athletic performance and skill. Specifically, the deletion allele (DD) of ACE was identified as a predictor for AF power (P≤0.008), endurance (P=0.001) and skill assessments (P≤0.003). In addition, polymorphisms in the brain-derived neurotrophic factor, D2 dopamine receptor, and catechol-O-methyltransferase genes were also shown to contribute to kicking skill outcomes (P≤0.044). This is the first study to implicate the ACE deletion allele for a multidimensional sport in such a way. Further, the results from this study have identified several new candidate genes in predicting athletic and technical skill outcomes.

Kinematic effects of a short-term fatigue protocol on punt-kicking performance

The punt kick is a fundamental skill used in several team sports; however, there has been a lack of research on how fatigue affects its technique. The purpose of this study was to determine the effects of short-term fatigue on punt-kicking performance. Eight elite and sub-elite Australian Football players performed maximal drop punt kicks on their preferred leg prior to, during and after a match-specific fatigue protocol. Optotrak Certus collected kinematic data from kick foot toe-off until ball contact. Repeated-measures analysis of variance showed a significant increase in 20 m sprint times after each short-term protocol, indicating fatigue. Foot speed did not significantly change with fatigue; however, increases in the range of motion at the pelvis and kicking thigh, along with increases in kicking thigh angular velocity, occurred. For the support leg, maximum knee flexion angular velocity increased while there was greater flexion found at the knee and hip, and greater range of motion at the knee. Players are able to make kinematic adaptations in order to maintain foot speed while punting for maximal distance after short-term efforts.

A Cross-Sectional Lower-Body Power Profile of Elite and Subelite Australian Football Players

Australian football (AF) is a sport which requires a vast array of physiological qualities, including high levels of strength and power. However, the power characteristics of AF players, particularly at the subelite level have not been extensively studied with further investigation warranted to understand the power capabilities and training requirements of elite and subelite AF groups. Therefore, the aim of this investigation was to develop a lower-body power profile of elite and subelite AF players. Eighteen elite and 12 subelite AF players completed a 1 repetition maximum (1RM) squat test to determine maximal lower-body strength, and countermovement jump (CMJ) and squat jump (SJ) testing to assess lower-body muscular power performance. Maximal lower-body strength was not statistically different between groups (p > 0.05). Elite players produced greater levels of peak power for CMJ at loads of 0, 30 (p < 0.05), and 40% (p < 0.01) of 1RM in comparison to subelite players. Squat jump peak power was statistically different between groups at 0, 20, 30, and 40% (p < 0.01) of 1RM; with elite players producing greater power than their subelite counterparts at all measured loads for SJ. Findings from this investigation demonstrate that elite AF players are able to generate greater levels of lower-body power than subelite AF players, despite no significant differences existing in maximal lower-body strength or body mass. As lower-body power levels clearly differentiate elite and subelite AF players, emphasis may be placed on improving the power levels of subelite players, particularly those aspiring to reach the elite level.

The Yo-Yo Intermittent Recovery Test (Level 1) to discriminate elite junior Australian football players

The Yo-Yo Intermittent Recovery (IR) Test is currently used to assess endurance performance in team sport athletes. However, to date, no data has been presented on its application to an elite junior Australian football (AF) playing group. Therefore, the aim of this study was to evaluate the Yo-Yo Intermittent Recovery Test Level 1 (IR1) ability to discriminate between junior AF players at two different playing standards and a group of non-athletic healthy males. Sixty age matched participants (16.6 ± 0.5 years) spread over three groups (20 per group): elite junior footballers; sub-elite junior footballers; and non-athletic healthy males participated in this study. Participants undertook a single Yo-Yo test performance on an indoor basketball court for each group. A one-way ANOVA with Scheffe's post hoc analysis revealed the elite junior footballers covered a significantly greater total distance ( p < 0.001) and completed a significantly greater number of high-intensity efforts ( p < 0.001) in comparison to their sub-elite counterparts, whilst both AF groups performed significantly better ( p < 0.001) than the non-athletic healthy males. This study demonstrates the ability of the Yo-Yo IR1 to discriminate endurance performance between elite and sub-elite AF players, whilst further distinguishing AF players from a non-athletic healthy control group.

Delayed Onset of Transversus Abdominus in Long-Standing Groin Pain

Long-standing groin pain is a persistent problem that is commonly difficult to rehabilitate. Theoretical rationale indicates a relationship between the motor control of the pelvis and long-standing groin pain; however, this link has not been investigated. The current experiment aimed to evaluate motor control of the abdominal muscles in a group of Australian football players with and without long-standing groin pain. Ten participants with long-standing groin pain and 12 asymptomatic controls were recruited for the study. Participants were elite or subelite Australian football players. Fine-wire and surface electromyography electrodes were used to record the activity of the selected abdominal and leg muscles during a visual choice reaction-time task (active straight leg raising). When the asymptomatic controls completed the active straight leg raise (ASLR) task, the transversus abdominus contracted in a feed-forward manner. However, when individuals with long-standing groin pain completed the ASLR task, the onset of transversus abdominus was delayed (P < 0.05) compared with the control group. There were no differences between groups for the onset of activity of internal oblique, external oblique, and rectus abdominus (all P > 0.05). The finding that the onset of transversus abdominus is delayed in individuals with long-standing groin pain is important, as it demonstrates an association between long-standing groin pain and transversus abdominus activation.

Isokinetic strength related to jumping but not kicking performance of Australian footballers

The relationships between lower limb strength and two Australian football (AF) skills were assessed for 19 sub-elite AF players. Knee extension (KE) and knee flexion (KF) strength were assessed using a Biodex isokinetic dynamometer at angular velocities of 60, 240 and 360 degrees/sec. The two AF skills evaluated were running vertical jump (VJ) and kicking performance (KP). VJ performance was defined as the maximal jump height measured with a Yardstick device. KP was gauged through video analysis, as the post-contact resultant ball velocity (BV) during maximal effort drop punt kicking. Strength was measured as the isokinetic peak torque (PT value. No significant correlations were detected between the isokinetic knee strength values and maximal kicking velocity. Low to moderate significant correlations (r = 0.55 - 0.69, p < 0.05) were detected between the isokinetic measures and VJ height. It may be inferred that additional strengthening of the knee musculature may enhance running VJ performance, but not necessarily kicking velocity for this group of sub-elite AF players.