This bill amends the Education Amendments of 1972, specifically Title IX, to establish a precise definition of "sex" for athletic programs. It mandates that for purposes of determining compliance in athletics, sex shall be recognized based solely on a person's reproductive biology and genetics at birth . Under this amendment, it would be a violation of Title IX for any recipient of federal financial assistance to allow an individual whose sex is male, as defined, to participate in athletic programs or activities designated for women or girls. The legislation clarifies that this prohibition encompasses all athletic programs and activities linked to team participation. However, it permits males to train or practice with women's or girls' programs, provided that no female is deprived of a roster spot, opportunity to participate, scholarship, or any other benefit associated with the program. Additionally, the bill directs the Comptroller General to conduct a study to determine the meaning of "any other benefit" and to document the adverse psychological, developmental, participatory, and sociological results for girls when males compete in female sports.