The Effects of a Semester of Preprofessional Dance Training on Biomarkers and Performance Variables in Elite Adolescent Ballet Dancers.

Abstract: Sanders, DJ, Murray, MS, McFadden, BA, Chandler, AJ, Walker, AJ, Bozzini, BN, Cintineo, HP, Bello, ML, Arent, MA, and Arent, SM. The effects of a semester of preprofessional dance training on biomarkers and performance variables in elite adolescent ballet dancers. J Strength Cond Res XX(X): 000-000, 2025-Early sport specialization exposes young athletes to high volumes of training. More knowledge is needed regarding the physiologic changes that may occur, particularly identifying differences between sexes. The purpose of this study was to evaluate biomarkers and performance changes in elite, preprofessional ballet dancers from the same training program. Male (N = 10) and female (N = 13) dancers participated in blood draws at the beginning of their semester (T1) and every 4 weeks thereafter (T2-T5). Performance was assessed pre- and postsemester (e.g., body composition, vertical jump, and V̇o2max). Repeated measures multivariate analysis of variance assessed performance and biomarker responses throughout the semester (p < 0.05). Sex-by-time interactions were observed for sex-hormone binding globulin, free cortisol, follicle stimulating hormone, and omega 6:3 ratio (p < 0.05). Sex effects were found in free triiodothyronine, testosterone, estradiol, growth hormone, creatine kinase (CK), percentage transferrin saturation, ferritin, and all performance tests (p < 0.05). Female dancers experienced further time effects in free thyroxine, follicle stimulating hormone, tumor necrosis factor alpha, omega 6:3 ratio, iron, percentage transferrin saturation, and ferritin (p < 0.05). Male dancers experienced further time effects in total triiodothyronine, total and free cortisol, CK, tumor necrosis factor alpha, vitamin D, percentage transferrin saturation, and ferritin (p < 0.05). Despite similar training, differential responses were observed between male and female dancers, particularly with regard to cortisol and hematologic markers. Adequate monitoring programs can help identify sex differences in response to training demands. Performance staff should account for and address these sex differences to enhance recovery outcomes.