Science, technology, engineering and mathematics (STEM) occupations represent one of the broadest gender gaps in any professional field, with women and girls grossly underrepresented in STEM education and careers, particularly engineering and biomechanics. Factors such as bias, stereotyping, and a lack of female role models can significantly influence women's and girls' decisions to enter and remain in the field of biomechanics. A critical first step in increasing the number of female biomechanists is to create early opportunities for girls to explore biomechanics. To address this, international initiatives, such as National Biomechanics Day (NBD), have been developed to expand the awareness, influence, and impact of biomechanics by engaging young people in school biomechanics programs. The Biomechanics Initiative, the official sponsor of NBD, offers grant programs aimed at empowering women to host an NBD event designed to promote biomechanics to girls and women in an immersive, interactive, and engaging manner. In 2021, Biomechanics Research Laboratory (BRL) Ph.D. student Maddison Kirk was a recipient of the grant program. In this paper we describe the BRL NBD event, which involved 20 female athletes from diverse backgrounds, demonstrating to them how biomechanics can be used to assess their physical fitness and performance. Female biomechanists and research assistants running the NBD event acted as female role models to participants, increasing the visibility of women in biomechanics and, in turn, helping to address current bias and stereotyping in STEM. By diversifying biomechanics and ensuring STEM fields are representative of the society in which we live, we can advance the field of biomechanics both nationally and internationally.