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

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

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.

(DOCX)</p

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

Frequency distributions of maturity timing (APHV) for <i>N</i> = 663 female 100-m FC swimmers plotted relative to expected female normative population APHV distributions.

Fig 1a illustrates ‘All’ sample distribution; 1b illustrates the distribution of 10–13 year-olds; and 1c illustrates the distribution of 14–15 year-olds.</p

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

(DOCX)</p

Revised maturity timing distributions, chi-square, and odds ratio analyses of 424 female swimmers (10/11-13 years) according to raw ‘All’, ‘Top 50%’ and ‘Top 25%’, and correctively adjusted ‘Top 50%’ and ‘Top 25%’ of swim times.

Revised maturity timing distributions, chi-square, and odds ratio analyses of 424 female swimmers (10/11-13 years) according to raw ‘All’, ‘Top 50%’ and ‘Top 25%’, and correctively adjusted ‘Top 50%’ and ‘Top 25%’ of swim times.</p