Maturation-based Corrective Adjustment Procedures (Mat-CAPs) in youth swimming: Evidence for restricted age-group application in females.

Inter-individual differences in maturation-associated development can lead to variations in physical performance, resulting in performance (dis)advantages and maturation selection bias within youth sport systems. To address such bias and account for maturational differences, Maturation-based Corrective Adjustment Procedures (Mat-CAPs) could be beneficial. The present study aimed to: (1) determine maturity timing distributions in youth female swimming; (2) quantify the relationship between maturation status and 100-m front-crawl (FC) performance; (3) implement Mat-CAPs to remove maturational influences upon swimming performance. For Aim 1 and 2, participants were 663 female (10–15 years) swimmers who participated in 100-m FC events at Australian regional, state, and national-level competitions between 2016–2020 and underwent anthropometric assessment (mass, height and sitting height) to estimate maturity timing and offset. For Aim 3, participants aged 10–13 years were categorised into maturity timing categories. Maturity timing distributions for Raw (‘All’, ‘Top 50%’ and ‘Top 25%’) and Correctively Adjusted swim times were examined. Chi-square, Cramer’s V and Odds Ratios determined the presence of maturation biases, while Mat-CAPs identified whether such biases were removed in targeted age and selection-groups. Results identified that between 10–13 years, a significantly higher frequency of ‘early’ maturers was apparent, although tapered toward higher frequencies of ‘Late-normative’ maturers by 14–15 years. A curvilinear relationship between maturity-offset and swim performance was identified (R2 = 0.51, p<0.001) and utilised for Mat-CAPs. Following Mat-CAPs application, maturity timing biases evident in affected age-groups (10–13 years), and which were magnified at higher selection levels (‘Top 50%’ & ‘25%’ of swim performances) were predominantly removed. Findings highlight how maturation advantages in females occurred until approximately 13 years old, warranting restricted Mat-CAPs application. Mat-CAPS has the potential to improve female swimmer participation experiences and evaluation

Removing Maturity Influences from Youth Swimming: The Development and Testing of Maturation Based Corrective Adjustment Procedures

Talent Identification (TI) programs aim to systematically identify athletes who display potential for future success within the given sport. The efficacy and utility of TI programs have come under scrutiny since many elite adult athletes are not identified through these programs. Growth and maturation are key processes influencing youth performance, with developmental changes posing numerous problems in being able to accurately evaluate youth performance prior to full maturation. Therefore, the overarching purposes of the present thesis were to conduct the first systematic review of literature on TI in youth swimming. Then, due to the confounding influence of maturation in TI assessment and based on considerations from the review, the primary study purpose was to further examine the relationships between maturation upon performance, with the aim to develop a technique that accounts for maturational differences in female youth swimming (i.e., Maturation-based Corrective Adjustment Procedures - Mat-CAPs). A systematic review was conducted, including 28 articles that examined TI within youth swimming. Inconsistent criteria were applied across studies to distinguish talented swimmers. Identified studies varied in participants, developmental stage, performance level and events; despite this, key factors were consistent within studies (i.e., swimming [in-water] specific, individual attributes; and environmental). It was found that swimming performance is dynamic and multifactorial, with complex interrelations between contributing factors. No consistent set of measures or factors were identified, with many contrasting findings evident in female performance. More diverse research is required before a comprehensive understanding of TI in youth swimming is achieved, specifically within identifying female youth swimmers. In the main study, a large sample (N = 663) of Australian female youth 100-m front-crawl (FC) swimmers underwent assessment of anthropometrics (mass, height and sitting height) and estimations of maturity timing and offset. Female 100-m FC performance (seconds) was also assessed at Australian regional, state, and national-level competitions between 2016-2020, with the relationship between maturation and performance quantified. Findings identified significant overrepresentations of ‘normative’ maturing swimmers, with a left shift toward early maturing participants. When examining performance times, significant maturation biases were present, skewed towards biologically older swimmers (i.e., higher maturation status), with increasing effect size according to selection level. When Mat-CAPs were applied, maturational biases in performance and selection levels were removed across age-groups where maturation was influential. In conclusion, further holistic, multifactorial research is necessary to improve the validity and effectiveness of TI in youth swimming. Practitioners need to carefully apply multifactorial assessments according to sex, developmental stage, and event demands to help improve TI processes in swimming. Maturity related inter-individual differences are critical to consider during development years, with likely complex relationships for youth females. This thesis demonstrates how Mat-CAPs has the capability to account for maturation status-based influences in female youth swimmers; helping provide a strategy for performance evaluation with maturational-related differences controlled. ‘Mat-CAPS’ has the potential to be more extensively applied, whether as part of TI practices or within more localised swim events, to help improve youth swimmer experiences

Re-balancing the Relative Age Effect Scales: Meta-analytical Trends, Causes, and Corrective Adjustment Procedures as a Solution

In making the case to re-balance relative age participation and attainment inequalities in sport (i.e. Relative Age Effects [RAEs]), the chapter highlights findings from meta-analytical studies conducted in male and female contexts. Second, this chapter identifies normative growth, and maturational-associated growth, between youth sport participants as the most likely underlying root causes, leading to RAEs. Informed by meta-analytical findings and root causes, the final part of the chapter presents “corrective adjustment procedures,” as a novel, feasible solution to RAEs for particular sport contexts. Here an explanation of their applications to date, implications, as well as challenges and limitations is provided

Maturity-related developmental inequalities in age-group swimming: the testing of ‘Mat-CAPs’ for their removal

Objectives: To (1) examine the association between maturity timing and performance-based selection levels in (N=708) Australian male 100-m Freestyle swimmers (12-17 years); (2) identify the relationship between maturation status and 100-m Freestyle performance; and (3) determine whether Maturation-based Corrective Adjustment Procedures (Mat-CAPs) could remove maturation-related differences in swimming performance. Methods: In Part 1, maturity timing category distributions ('Early', 'Early Normative', 'Late Normative' and 'Late') for 'All', 'Top 50%' and '25%' of raw swimming times were examined within and across age-groups. In Part 2, multiple regression analyses quantified the relationship between maturity offset (YPHV) and swimming performance. In Part 3, sample-based maturity timing category distributions were examined based on raw and correctively adjusted swim times for 12-17 year old age-groups. Results: Based on raw swim times, a high prevalence of 'Early-maturing' swimmers, with large effect sizes was identified (e.g., 14 years 'All' - χ2 (3, 151=111.98, p<0.001; 'Early' v 'Late' OR=82.0 95%CI=4.77, 1409.9); while a complete absence of 'Late-maturers' was apparent in the sample (N=708). When maturity categories were re-defined based on sample mean±standard deviation, and when using the expected curvilinear trendline identified in Part 2, Mat-CAPs mitigated maturity timing biases across all age-groups and selection levels, and removed the Freestyle performance advantage afforded by advanced maturity timing and status. Conclusions: Removing the influence of maturation-related developmental differences could help improve youth swimmer participation experiences and improve the accuracy of identifying genuinely skilled age-group swimmers

The curvilinear relationship between maturity status (YPHV) and 100-m FC performance time (sec) in females aged 10–15 years at regional-national level competitions.

The curvilinear relationship between maturity status (YPHV) and 100-m FC performance time (sec) in females aged 10–15 years at regional-national level competitions.</p

Youth female participant (<i>N</i> = 663) characteristics and 100-m FC mean performance time.

Youth female participant (N = 663) characteristics and 100-m FC mean performance time.</p

Data summarising raw sample maturity timing distributions, chi-square, and odds ratio analyses of 663 female swimmers (10–15 years) in comparison to the expected distributions in the normative female population.

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Maturity timing distributions of raw and correctively adjusted swim times in 100-m FC swimming according to selection levels for 12 years old.

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