We know what we know, but from whom did we learn it? A sociodemographic history of participant characteristics and reporting practices in sport and exercise psychology.

The majority of research participants in the social sciences are recruited from populations that are Western, educated, industrialized, rich, and democratic. This has the potential to threaten the external validity and limit the generalizability of research findings. It also highlights the need to provide a historical accounting of participant characteristics and reporting practices across coherent disciplines of research. This paper reports the participant characteristics from studies published in 12 leading journals in the sport and exercise psychology literature. In total, 15,650 peer-reviewed articles were published across these outlets from 1930 to 2021, involving 4,487,437 human participants. A descriptive overview of participant characteristics and reporting practices suggests that empirical understanding of human experiences and outcomes in sport and exercise settings is built from an incomplete and unrepresentative sample of participants. Findings illuminate potential knowledge gaps that may have resulted from the lack of diverse samples and offer potential paths forward for contemporary sport and exercise psychology scholars who wish to address these gaps.