Case Report: Integrated physiological and performance profiling of an elite athlete with differences of sex development

Abstract

Background Recent developments in athlete eligibility frameworks, including sex-determining region Y (SRY) gene screening, have renewed focus on the biological basis of sex classification in sport. However, the relationship between genetic and endocrine markers and sport-specific performance remains incompletely understood, particularly in athletes with differences of sex development (DSD). Objective To demonstrate a multidimensional, sport-specific framework for evaluating elite athletes with DSD, in whom genetic, endocrine and performance characteristics may not align uniformly with binary sex categories. Methods An integrated multidimensional physiological assessment was conducted in an elite football athlete with DSD. Assessments included endocrine profiling, whole-genome sequencing, body composition, neuromuscular performance, pulmonary function, aerobic capacity, and sport-specific field testing. Results were benchmarked against published elite football datasets and in-house comparator cohorts using z-scores. Results The 46,XY DSD athlete with a homozygous pathogenic SRD5A2 variant (c.578A > G) and a markedly elevated T:DHT ratio demonstrated heterogeneous physiological and football-specific performance characteristics across domains. Sprint ability and explosive power were above elite female football references, while strength and aerobic capacity were broadly comparable with female reference values. Conclusion This case illustrates the value of evaluating athletes using sport-specific physiological and performance data rather than isolated biological markers alone. Accumulation of similar multidimensional datasets may help inform more evidence-based, sport-specific approaches to athlete evaluation.