An Investigation of Relative Age Effect in Youth Football

Background. Youth sport programs typically group children based on an annual birthdate cut-off (e.g., U8, U9, U10). However, research indicates this results in relative age effect (RAE), the overrepresentation of children born early in the selective year and underrepresentation of children born later (Barnsley et al., 1985), which inadvertently advantages older and more biologically mature children (Hancock et al., 2013). Sports in which physical size contributes to success often have a more pronounced RAE from youth to professional levels; however, studies of American football at the professional level have not observed RAE. This absence is speculated to be a product of youth football policies that use additional factors, such as weight and skill level, coupled with age to group children (Wattie et al., 2015). Interestingly though, RAE has not yet been studied in youth football. Therefore, the purpose of this study was to determine the extent to which RAE is promoted or diminished when grouping children by various developmental factors (i.e., age, weight, and skill level). Method. Data was acquired from a mid-Atlantic youth football registration database that used a standardized weight matrix to organize children of various ages and grouped them into teams based on their skill assessment. A purposive sample (N = 1,265) of 8-13 year old boys was extracted and classified into quartiles based upon birth month for data analysis. Multiple chi-square goodness of fit tests were run using expected values of live birth from the CDC. Results. The mean age of the sample was 11.0 years. Chi-square goodness of fit tests indicated significant differences (p \u3c .001) of departures from expected frequencies when independently categorized by age only (AO), weight only (WO), and skill level only (SO). However, there were fewer significant departures when categorized by age + weight + skill level (AWS). Discussion. The findings from this study provide youth sport programs with needed data to for considering alternative organizing practices were grouping children together. Specifically our study indicates using a singular developmental criterion to group children together (e.g., by age, promotes RAE, whereas a more robust developmental approach appears to alleviate RAE. (e.g., age + weight + skill level). This is significant because the absence of RAE provides children with the opportunity to develop sport-specific skills in a fairer environment among their peers with more developmentally appropriate instruction (Wattie et al., 2008), which promotes more positive sport-based, physical activity experiences for them