Female Athlete Research

The Female Athlete Science and Translational Research (FASTR) Program at Stanford University is dedicated to advancing research fostering innovation for female athletes of all ages. Our research encompasses mental health, nutrition, bone health with an emphasis on the Female Athlete Triad (Triad) and Relative Energy Deficiency in Sport (RED-S). 

To learn more about the FASTR Program, please visit: https://fastr.su.domains/


Clinical Assistant Professor, Orthopaedic Surgery


  • Centering the female athlete voice in a sports science research agenda: a modified Delphi survey with Team USA athletes. British journal of sports medicine McCleery, J., Diamond, E., Kelly, R., Li, L., Ackerman, K. E., Adams, W. M., Kraus, E. 2024


    To co-construct a sports medicine and exercise science research and translational agenda with Team USA elite female athletes serving as the experts on their health, performance and well-being.40 Team USA female athletes across sports disciplines participated in an online, anonymous, modified Delphi survey by ranking topics on a Likert scale (1='strongly disagree' and 5='strongly agree') and providing qualitative justification regarding whether they believed having more information and research on each topic would support their athletic performance, health and well-being. After each Delphi round, quantitative rankings of topics and qualitative justifications were analysed, informing revisions to the list of topics for review in the subsequent round. Researchers provided athletes with a detailed report of findings and revisions following each round.The final list contained 14 ranked topics. The top five were menstrual cycle symptoms (4.58±0.74), recovery (4.58±0.59), birth control (4.55±0.89), mental health (4.50±0.55) and fueling and the menstrual cycle (4.43±0.74). New topics originating from athletes included recovery, menstrual cycle symptoms, fueling and the menstrual cycle, mental health and sports performance, team dynamics, and institutionalised sexism.This is the first study to co-construct a research and translational agenda with Team USA elite female athletes. The list of sports science research topics developed by focusing on elite female athletes' voices lays the foundation for future research and provides valuable insight into the specific needs of female athletes.

    View details for DOI 10.1136/bjsports-2023-107886

    View details for PubMedID 38981661

  • Risk Factors for Running-Related Injury in High School and Collegiate Cross Country Runners: A Systematic Review. The Journal of orthopaedic and sports physical therapy Joachim, M. R., Kuik, M. L., Krabak, B. J., Kraus, E. M., Rauh, M. J., Heiderscheit, B. C. 2023: 1-36


    OBJECTIVE: To summarize and describe risk factors for running-related injuries (RRI) among high school and collegiate cross country runners. DESIGN: Descriptive systematic review. LITERATURE SEARCH: Four databases (Scopus, SPORTDiscus, CINAHL, Cochrane) were searched from inception to August 2023. STUDY SELECTION CRITERIA: Studies assessing RRI risk factors in high school or collegiate runners using a prospective design with at least one season of follow-up were included. DATA SYNTHESIS: Results across each study for a given risk factor were summarized and described. The NOS and GRADE frameworks were used to evaluate quality of each study and certainty of evidence for each risk factor. RESULTS: Twenty-four studies were included. Overall, study quality and certainty of evidence was low to moderate. Females or runners with prior RRI or increased RED-S risk factors were most at-risk for RRI, as were runners with a quadriceps angle >20° and lower step rates. Runners with weaker thigh muscle groups had increased risk of anterior knee pain. Certainty in evidence regarding training, sleep, and specialization was low, but suggests changes in training volume, poorer sleep, and increased specialization may increase RRI risk. CONCLUSION: The strongest predictors of RRI in high school and collegiate cross country runners are sex and RRI history, which are non-modifiable. There is moderate certainty that increased RED-S risk factors increase RRI risk, particularly bone stress injuries. There is limited evidence that changes in training and sleep quality influence RRI risk, but these are modifiable factors that should be studied further in this population.

    View details for DOI 10.2519/jospt.2023.11550

    View details for PubMedID 37970801

  • Mental Health Matters: A Cross-Sectional Survey on Depression and Anxiety Symptoms and the Female and Male Athlete Triad CLINICAL JOURNAL OF SPORT MEDICINE Olson, E., Miro, E., Roche, M., Mehta, S., Sainani, K., Kraus, E. 2023; 33 (4): 368-375
  • Healthy Runner Project: a 7-year, multisite nutrition education intervention to reduce bone stress injury incidence in collegiate distance runners. BMJ open sport & exercise medicine Fredericson, M., Roche, M., Barrack, M. T., Tenforde, A., Sainani, K., Kraus, E., Kussman, A., Miller Olson, E., Kim, B. Y., Fahy, K., Miller, E., Diamond, E., Meraz, S., Singh, S., Nattiv, A. 2023; 9 (2): e001545


    Objectives: We evaluated the effect of a nutrition education intervention on bone stress injury (BSI) incidence among female distance runners at two NCAA Division I institutions.Methods: Historical BSI rates were measured retrospectively (2010-2013); runners were then followed prospectively in pilot (2013-2016) and intervention (2016-2020) phases. The primary aim was to compare BSI rates in the historical and intervention phases. Pilot phase data are included only for descriptive purposes. The intervention comprised team nutrition presentations focused on optimising energy availability plus individualised nutrition sessions for runners with elevated Female Athlete Triad risk. Annual BSI rates were calculated using a generalised estimating equation Poisson regression model adjusted for age and institution. Post hoc analyses were stratified by institution and BSI type (trabecular-rich or cortical-rich).Results: The historical phase included 56 runners and 90.2 person-years; the intervention phase included 78 runners and 137.3 person-years. Overall BSI rates were not reduced from the historical (0.52 events per person-year) to the intervention (0.43 events per person-year) phase. Post hoc analyses demonstrated trabecular-rich BSI rates dropped significantly from 0.18 to 0.10 events per person-year from the historical to intervention phase (p=0.047). There was a significant interaction between phase and institution (p=0.009). At Institution 1, the overall BSI rate dropped from 0.63 to 0.27 events per person-year from the historical to intervention phase (p=0.041), whereas no decline was observed at Institution 2.Conclusion: Our findings suggest that a nutrition intervention emphasising energy availability may preferentially impact trabecular-rich BSI and depend on team environment, culture and resources.

    View details for DOI 10.1136/bmjsem-2023-001545

    View details for PubMedID 37180969

  • Prevalence of Female and Male Athlete Triad Risk Factors in Ultramarathon Runners. Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine Hoeg, T. B., Olson, E. M., Skaggs, K., Sainani, K., Fredericson, M., Roche, M., Kraus, E. 2021


    OBJECTIVE: To identify the prevalence of male and female athlete triad risk factors in ultramarathon runners and explore associations between sex hormones and bone mineral density (BMD).DESIGN: Multiyear cross-sectional study.SETTING: One hundred-mile ultramarathon.PARTICIPANTS: Competing runners were recruited in 2018 and 2019.ASSESSMENT OF RISK FACTORS: Participants completed a survey assessing eating behaviors, menstrual history, and injury history; dual-energy x-ray absorptiometry for BMD; and laboratory evaluation of sex hormones, vitamin D, and ferritin (2019 cohort only).MAIN OUTCOME MEASURE: A Triad Cumulative Risk Assessment Score was calculated for each participant.RESULTS: One hundred twenty-three runners participated (83 males and 40 females, mean age 46.2 and 41.8 years, respectively). 44.5% of men and 62.5% of women had elevated risk for disordered eating. 37.5% of women reported a history of bone stress injury (BSI) and 16.7% had BMD Z scores <-1.0. 20.5% of men had a history of BSI and 30.1% had Z-scores <-1.0. Low body mass index (BMI) (<18.5 kg/m2) was seen in 15% of women and no men. The Triad Cumulative Risk Assessment classified 61.1% of women and 29.2% of men as moderate risk and 5.6% of both men and women as high risk.CONCLUSIONS: Our study is the first to measure BMD in both male and female ultramarathon runners. Our male population had a higher prevalence of low BMD than the general population; females were more likely to report history of BSI. Risk of disordered eating was elevated among our participants but was not associated with either low BMD or low BMI.

    View details for DOI 10.1097/JSM.0000000000000956

    View details for PubMedID 34232162

  • The Male Athlete Triad-A Consensus Statement From the Female and Male Athlete Triad Coalition Part 1: Definition and Scientific Basis. Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine Nattiv, A., De Souza, M. J., Koltun, K. J., Misra, M., Kussman, A., Williams, N. I., Barrack, M. T., Kraus, E., Joy, E., Fredericson, M. 2021


    ABSTRACT: The Male Athlete Triad is a syndrome of 3 interrelated conditions most common in adolescent and young adult male endurance and weight-class athletes and includes the clinically relevant outcomes of (1) energy deficiency/low energy availability (EA) with or without disordered eating/eating disorders, (2) functional hypothalamic hypogonadism, and (3) osteoporosis or low bone mineral density with or without bone stress injury (BSI). The causal role of low EA in the modulation of reproductive function and skeletal health in the male athlete reinforces the notion that skeletal health and reproductive outcomes are the primary clinical concerns. At present, the specific intermediate subclinical outcomes are less clearly defined in male athletes than those in female athletes and are represented as subtle alterations in the hypothalamic-pituitary-gonadal axis and increased risk for BSI. The degree of energy deficiency/low EA associated with such alterations remains unclear. However, available data suggest a more severe energy deficiency/low EA state is needed to affect reproductive and skeletal health in the Male Athlete Triad than in the Female Athlete Triad. Additional research is needed to further clarify and quantify this association. The Female and Male Athlete Triad Coalition Consensus Statements include evidence statements developed after a roundtable of experts held in conjunction with the American College of Sports Medicine 64th Annual Meeting in Denver, Colorado, in 2017 and are in 2 parts-Part I: Definition and Scientific Basis and Part 2: The Male Athlete Triad: Diagnosis, Treatment, and Return-to-Play. In this first article, we discuss the scientific evidence to support the Male Athlete Triad model.

    View details for DOI 10.1097/JSM.0000000000000946

    View details for PubMedID 34091537

  • The Male Athlete Triad-A Consensus Statement From the Female and Male Athlete Triad Coalition Part II: Diagnosis, Treatment, and Return-To-Play. Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine Fredericson, M., Kussman, A., Misra, M., Barrack, M. T., De Souza, M. J., Kraus, E., Koltun, K. J., Williams, N. I., Joy, E., Nattiv, A. 2021


    ABSTRACT: The Male Athlete Triad is a medical syndrome most common in adolescent and young adult male athletes in sports that emphasize a lean physique, especially endurance and weight-class athletes. The 3 interrelated conditions of the Male Athlete Triad occur on spectrums of energy deficiency/low energy availability (EA), suppression of the hypothalamic-pituitary-gonadal axis, and impaired bone health, ranging from optimal health to clinically relevant outcomes of energy deficiency/low EA with or without disordered eating or eating disorder, functional hypogonadotropic hypogonadism, and osteoporosis or low bone mineral density with or without bone stress injury (BSI). Because of the importance of bone mass acquisition and health concerns in adolescence, screening is recommended during this time period in the at-risk male athlete. Diagnosis of the Male Athlete Triad is best accomplished by a multidisciplinary medical team. Clearance and return-to-play guidelines are recommended to optimize prevention and treatment. Evidence-based risk assessment protocols for the male athlete at risk for the Male Athlete Triad have been shown to be predictive for BSI and impaired bone health and should be encouraged. Improving energetic status through optimal fueling is the mainstay of treatment. A Roundtable on the Male Athlete Triad was convened by the Female and Male Athlete Triad Coalition in conjunction with the 64th Annual Meeting of the American College of Sports Medicine in Denver, Colorado, in May of 2017. In this second article, the latest clinical research to support current models of screening, diagnosis, and management for at-risk male athlete is reviewed with evidence-based recommendations.

    View details for DOI 10.1097/JSM.0000000000000948

    View details for PubMedID 34091538

Faculty Contact

Dr Emily Kraus

Research Contact

Abby McIntyre