Body composition and bone health outcomes across positional groups in Netball Super League (NSL) senior and under-21 players; a multi-year cohort study.

Background: Body composition and bone health are important for netball from a performance and health perspective (e.g., bone stress injury), given the typical characteristics of players and demands of the game. Objectives: The objectives of this study are to quantify and compare the positional group-specific body composition and site-specific bone health outcomes of netball players and to establish within-season changes in these variables. Methods: Forty-seven female netball players (senior: n=23, under-21: n=24) from one Netball Super League (NSL) franchise participated across three seasons (2021-2023). Dual-energy X-ray absorptiometry (DEXA) scans were conducted four times per season. Total body, anteroposterior lumbar spine and total hip scans were performed. General and generalised linear mixed models were used to compare positional groups and age groups, and to investigate within-season changes. Results: Goal circle netball players had greater total mass and bone mass than midcourt netball players at both levels ( Conclusion: These findings highlight the importance of continued physical development in the under-21 squad before progressing to a senior squad, as well as the need for individualised approaches to nutritional and training interventions that support physical development, addressing positional requirements and developmental stages. Future research should explore longitudinal body composition trajectories across career phases and multiple teams to refine normative benchmarks.