Dr. Kraus is a Clinical Assistant Professor at Stanford Children’s Orthopedic and Sports Medicine Center trained in the specialty of Physical Medicine and Rehabilitation (PM&R) sports medicine. She has research and clinical interests in endurance sports medicine, injury prevention, running biomechanics, prevention of bone stress injuries, and the promotion of health and wellness at any age of life. Dr. Kraus is the director of the FASTR Program, which stands for Female Athlete Science and Translational Research. The FASTR program is supported by the Wu Tsai Human Performance Alliance and seeks to close the gender gap in sports science research with an emphasis on early identification and interventions to prevent injury and identify ways to optimize performance in female athletes. Dr. Kraus is also a member of the U.S. Olympic and Paralympic Committee Women's Health Task Force and is the medical director of the Stanford Children's Motion Analysis and Sport Performance Lab. She has completed nine marathons including the Boston Marathon twice and one 50k ultramarathon. With running and staying physically active as one of her personal passions, she recognizes the importance of fitness for overall wellbeing and the prevention of chronic medical conditions.

Clinical Focus

  • Female Athlete Triad
  • Running Injuries
  • Stress Fractures
  • Overuse Injuries
  • Concussions
  • Sports Medicine

Professional Education

  • Board Certification: American Board of Physical Medicine and Rehabilitation, Physical Medicine and Rehab (2017)
  • Board Certification: American Board of Physical Medicine and Rehabilitation, Sports Medicine (2017)
  • Fellowship: Stanford University Sports Physical Med and Rehab Fellowship (2017) CA
  • Residency: Stanford University Physical Medicine and Rehabiliation (2016) CA
  • Internship: University of Nebraska Medical Center Internal Medicine Residency (2013) NE
  • Medical Education: University of Nebraska College of Medicine (2012) NE

2023-24 Courses

Stanford Advisees

All Publications

  • Infographic. Head to toe considerations for the postpartum endurance athlete. British journal of sports medicine Afifi, T., Barrack, M. T., Casey, E., Huddle, M., Kliethermes, S. A., Kraus, E., Toresdahl, B. G., Wasfy, M. M., Tenforde, A. S. 2024

    View details for DOI 10.1136/bjsports-2023-107624

    View details for PubMedID 38448197

  • 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., Olson, E., Kim, B., Fahy, K., Miller, E., Diamond, E., Meraz, S., Singh, S., Nattiv, A. 2024; 10 (1)
  • 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

  • Perception Of Thinness Promoting Faster Running Is Associated With Lower Energy Availability In Collegiate Runners Barrack, M. T., Fredericson, M., Sainani, K., Kraus, E., Roche, M., Diamond, E., Lewis, T., McIntyre, A., Nattiv, A. LIPPINCOTT WILLIAMS & WILKINS. 2023: 776
  • The Menstrual Cycle; A Priority Research Area For Team Usa Female Athletes Diamond, E., McCleery, J., Kelly, R. K., Li, J., Adams, W. M., Ackerman, K. E., Kraus, E. LIPPINCOTT WILLIAMS & WILKINS. 2023: 8
  • Team Dynamics And Interpersonal Relationships: An Area Of Research Priority For Elite Female Athletes McCleery, J., Kraus, E., Kelly, R., Diamond, E., Li, L., Adams, W., Ackerman, K. LIPPINCOTT WILLIAMS & WILKINS. 2023: 718
  • A Novel Approach To Female Athlete Sports Science Education McIntyre, A., Roche, M., Oliver, C., Boyd, T., Kraus, E. LIPPINCOTT WILLIAMS & WILKINS. 2023: 333-334
  • Higher Triad Risk Scores Are Associated With Increased Risk for Trabecular-Rich Bone Stress Injuries in Female Runners. Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine Roche, M., Nattiv, A., Sainani, K., Barrack, M., Kraus, E., Tenforde, A., Kussman, A., Olson, E. M., Kim, B., Fahy, K., Miller, E., Diamond, E., Meraz, S., Singh, S., Nattiv, A., Fredericson, M. 2023


    OBJECTIVE: Bone stress injuries (BSIs) in trabecular-rich bone are associated with greater biological risk factors compared with cortical-rich bone. We hypothesized that female runners with high Female Athlete Triad (Triad)-related risk would be at greater risk for trabecular-rich BSIs than runners with low Triad-related risk.DESIGN: Prospective cohort study.SETTING: Two NCAA institutions.PARTICIPANTS: Female runners were followed prospectively for up to 5 years.INTERVENTION: The intervention consisted of team nutrition presentations focused on optimizing energy availability plus individualized nutrition sessions. Triad Cumulative Risk Assessment (CRA) categories were assigned yearly based on low-energy availability, menstrual status, age of menarche, low body mass index, low bone mineral density, and prior BSI.MAIN OUTCOME MEASURES: The outcome was the annual incidence of trabecular- and cortical-rich BSI. Generalized Estimating Equations (GEE, to account for the correlated nature of the observations) with a Poisson distribution and log link were used for statistical modeling.RESULTS: Cortical-rich BSI rates were higher than trabecular-rich BSI rates (0.32 vs 0.13 events per person-year). Female runners with high Triad-related risk had a significantly higher incidence rate ratio of trabecular-rich BSI (RR: 4.40, P = 0.025) and cortical-rich BSI (RR: 2.87, P = 0.025) than women with low Triad-related risk. Each 1-point increase in Triad CRA score was associated with a significant 26% increased risk of trabecular-rich BSI (P = 0.0007) and a nonsignificant 14% increased risk of cortical-rich BSI (P = 0.054).CONCLUSIONS: Increased Triad CRA scores were strongly associated with increased risk for trabecular-rich BSI. Incorporating Triad CRA scores in clinical care could guide BSI prevention.

    View details for DOI 10.1097/JSM.0000000000001180

    View details for PubMedID 37655940

  • Biomechanical And Perceived Effort Responses Of Adolescent Runners To Cadence Manipulation In A Natural Environment Garcia, M. C., Heiderscheit, B. C., Kraus, E., Murray, A. M., Norte, G. E., Bazett-Jones, D. M. LIPPINCOTT WILLIAMS & WILKINS. 2023: 655-656
  • 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
  • Tarsal Navicular Bone Stress Injuries: A Multicenter Case Series Investigating Clinical Presentation, Diagnostic Approach, Treatment, and Return to Sport in Adolescent Athletes. The American journal of sports medicine Mehta, S., Zheng, E., Heyworth, B. E., Rizzone, K., Halstead, M., Brown, N., Stinson, Z., Nussbaum, E. D., Gray, A., Segovia, N., Kraus, E. 2023: 3635465231170399


    BACKGROUND: Tarsal navicular bone stress injuries (BSIs) are considered "high risk" because of prolonged healing times and higher rates of nonunion in adult populations but, to our knowledge, have not been comprehensively examined in adolescent athletes.PURPOSE: To describe the characteristics of tarsal navicular BSIs in adolescents.STUDY DESIGN: Case series; Level of evidence, 4.METHODS: A retrospective analysis of patients aged 10 to 19 years with a radiographically diagnosed tarsal navicular BSI was performed at 8 academic centers over a 9-year study period. Age, sex, body mass index (BMI), primary sport, physical examination findings, imaging, treatment, surgical technique, return-to-sport time, and complications were analyzed.RESULTS: Among 110 patients (mean age, 14.7 ± 2.7 years; 65% female), common primary sports were cross-country/track and field (29/92 [32%]) and gymnastics/dance (25/92 [27%]). Grade 4 BSIs were identified in 44% (48/110) of patients, with fracture lines present on radiography or magnetic resonance imaging. Nonoperative treatment (mean age, 14.4 ± 2.6 years), consisting of protected weightbearing and either a protective boot (69/88 [78%]) or a cast (19/88 [22%]), was trialed in all patients and was successful in 94 patients (85%). Operative treatment (mean age, 17.1 ± 1.4 years) was ultimately pursued for 16 patients (15%). Patients who required surgery had a higher BMI and a higher percentage of fracture lines present on imaging (nonoperative: 36/94 [38%]; operative: 14/16 [88%]). The median time to return to weightbearing, running, and full sport was significantly longer in duration for the operative group than the nonoperative group (P <.05). Complications associated with surgery included 1 case each of delayed union, nonunion, and painful implants, the latter of which required secondary surgery.CONCLUSION: Adolescent tarsal navicular BSIs were identified most commonly in female patients in leanness sports. Adolescents who required surgery were more likely to be older, have higher BMIs, and have grade 4 BSIs, and they returned to sport within a median of 5 months after single- or double-screw fixation with a low risk of postoperative complications. A better understanding of the presenting signs and symptoms and appropriate diagnostic imaging of navicular BSIs may lead to an earlier diagnosis and improved outcomes.

    View details for DOI 10.1177/03635465231170399

    View details for PubMedID 37265102

  • Preferred temporal-spatial parameters, physical maturation, and sex are related to vertical and braking forces in adolescent long-distance runners. Sports biomechanics Garcia, M. C., Heiderscheit, B. C., Kraus, E. A., Norte, G. E., Murray, A. M., Bazett-Jones, D. M. 2023: 1-11


    For adults, increasing cadence reduces ground reaction forces, but a lower preferred cadence does not predispose adults to experience higher ground reaction forces. Pubertal growth and motor control changes influence running mechanics, but it is unknown if preferred cadence or step length are associated with ground reaction forces for pre-adolescent and adolescent runners. Pre-adolescent and adolescent runners underwent an overground running analysis at a self-selected speed. Mixed model multiple linear regressions investigated the associations of preferred cadence, step length, physical maturation, and sex on ground reaction forces, while accounting for running speed and leg length. Running with a lower preferred cadence or longer preferred step length was associated with larger peak braking and vertical forces (p ≤ .01), being less physically mature was associated with larger vertical impact peak force and vertical loading rate (p ≤ .01), and being a male was associated with larger loading rates (p ≤ .01). A lower preferred cadence or longer preferred step length were associated with higher braking and vertical forces and being less physically mature or a male were associated with higher loading rates. An intervention to increase cadence/decrease step length could be considered if ground reaction forces are a concern for an adolescent runner.

    View details for DOI 10.1080/14763141.2023.2218325

    View details for PubMedID 37246741

  • 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

  • One size does not fit all: Influence of sex and maturation on temporal-spatial parameters for adolescent long-distance runners. Journal of sports sciences Garcia, M. C., Heiderscheit, B. C., Murray, A. M., Norte, G. E., Kraus, E., Bazett-Jones, D. M. 2022: 1-6


    Runners and coaches are often interested in identifying the "ideal" running form to reduce the risk of injury and improve performance. While differences in pelvis and hip motion have been reported among adolescent female and male long-distance runners of different stages of physical maturation, the influence of sex and/or maturation on temporal-spatial parameters is unknown for adolescent runners. Adolescent runners of different stages of physical maturation (pre-, mid-, post-pubertal) completed an overground running analysis at a self-selected speed. We performed 2*3 ANCOVAs (covariate=running speed) to compare temporal-spatial parameters among sex and maturation groups. Pre-adolescents ran with higher cadences and shorter step lengths than mid- (p ≤.01) and post-pubertal adolescents (p ≤.01), respectively. Mid-pubertal males and post-pubertal females also ran with higher cadences and shorter step lengths than post-pubertal males (p ≤.01). When step length was normalized to leg length, less physically mature runners demonstrated longer normalized step lengths (p ≤.01). Caution is advised when using a "one-size-fits-all" approach for recommending an "ideal" cadence and/or step length for adolescent long-distance runners. A runner's sex, stage of physical maturation and leg length should be considered when assessing and prescribing cadence and/or step length.

    View details for DOI 10.1080/02640414.2022.2142743

    View details for PubMedID 36352559

  • Analysis of limb kinetic asymmetry during a drop vertical jump in adolescents post anterior cruciate ligament reconstruction. Clinical biomechanics (Bristol, Avon) Bakal, D. R., Morgan, J. J., Lyons, S. M., Chan, S. K., Kraus, E. A., Shea, K. G. 2022; 100: 105794


    BACKGROUND: Limb asymmetry after ACL reconstruction is often cited as a risk factor for ACL reinjury. We assessed ground reaction forces on each limb during a drop vertical jump, and compared kinetic symmetry between limbs in adolescents post-ACL reconstruction versus healthy controls.METHODS: Forty-four participants who underwent an ACL reconstruction (16 male/28 female, mean age 16.1±1.5, mean 7.3±0.9months post-ACL reconstruction) and 34 controls (20 male/14 female, mean age 14.9±1.1) completed a drop vertical jump captured on a Vicon system and Bertec force plates. Kinetic variables were calculated individually for each limb. Inter-limb asymmetry was calculated as an index between each limb (involved versus uninvolved for the ACL reconstruction group, and left versus right for controls), and was compared between groups using independent t-tests.FINDINGS: Asymmetry was significantly more pronounced in the ACL reconstruction group versus the controls for peak contact ground reaction force (11.6% vs 4.4%, p=0.009), eccentric impulse (8.8% vs 3.8%, p=0.009), eccentric mean force (8.0% vs 3.4%, p=0.006), concentric peak ground reaction force (4.1% vs 0.8%, p=0.003), concentric impulse (5.1% vs 1.1%, p=0.001), and peak landing ground reaction force (12.7% vs 1.7%, p<0.001).INTERPRETATION: Limb kinetic asymmetry during a drop vertical jump was more pronounced in adolescents post-ACL reconstruction versus controls for both eccentric- and concentric-phase variables, which may indicate the use of compensatory strategies to offload the post-operative limb. Targeted interventions to produce more symmetric loading and unloading during jumping tasks should be developed, tested, and monitored to determine the impact on rehabilitation programs, return-to-sport evaluations, and injury prevention outcomes.

    View details for DOI 10.1016/j.clinbiomech.2022.105794

    View details for PubMedID 36270179

  • Stress Injuries of the Knee. Clinics in sports medicine Kraus, E., Rizzone, K., Walker, M., Brown, N., Kaur, J., Magrini, D., Glover, J., Nussbaum, E. 2022; 41 (4): 707-727


    Stress injuries to the bone and physis of the knee are common in the active adolescent patient and can be broken down into bone stress injuries (BSIs) and chronic physeal stress injuries. BSIs result from prolonged, repetitive bone loading, whereas chronic physeal stress injuries develop from repetitive loading to the apophysis or epiphysis. Most stress injuries of the knee resolve with relative rest but will occasionally need surgical intervention in more severe cases. Early and accurate identification is paramount for optimal management and to avoid long-term consequences.

    View details for DOI 10.1016/j.csm.2022.05.008

    View details for PubMedID 36210167

  • Dietary Behaviors Associated With Lower Nutrient Intake In Collegiate Endurance Runners Barrack, M. T., Fredericson, M., Kraus, E., Tenforde, A., Roche, M., Kussman, A., Gravani, K., Ansari, Y., Olson, C., Nattiv, A. LIPPINCOTT WILLIAMS & WILKINS. 2022: 590
  • Evaluating Genetic Predictors Of Bone Health In Ultramarathon Runners: Are Females Overriding Their Genetic Predisposition? Roche, M., Sainani, K., Walker, M., Kelly, R., Fredericson, M., Kraus, E. LIPPINCOTT WILLIAMS & WILKINS. 2022: 526-527
  • Medical and Biomechanical Risk Factors for Incident Bone Stress Injury in Collegiate Runners: Can Plantar Pressure Predict Injury? Orthopaedic journal of sports medicine Wilzman, A. R., Tenforde, A. S., Troy, K. L., Hunt, K., Fogel, N., Roche, M. D., Kraus, E., Trikha, R., Delp, S., Fredericson, M. 2022; 10 (6): 23259671221104793


    Background: Bone stress injury (BSI) is a common reason for missed practices and competitions in elite track and field runners.Hypothesis: It was hypothesized that, after accounting for medical risk factors, higher plantar loading during running, walking, and athletic movements would predict the risk of future BSI in elite collegiate runners.Study Design: Cohort study; Level of evidence, 2.Methods: A total of 39 elite collegiate runners (24 male, 15 female) were evaluated during the 2014-2015 academic year to determine the degree to which plantar pressure data and medical history (including Female and Male Athlete Triad risk factors) could predict subsequent BSI. Runners completed athletic movements while plantar pressures and contact areas in 7 key areas of the foot were recorded, and the measurements were reported overall and by specific foot area. Regression models were constructed to determine factors related to incident BSI.Results: Twenty-one runners (12 male, 9 female) sustained ≥1 incident BSI during the study period. Four regression models incorporating both plantar pressure measurements and medical risk factors were able to predict the subsequent occurrence of (A) BSIs in female runners, (B) BSIs in male runners, (C) multiple BSIs in either male or female runners, and (D) foot BSIs in female runners. Model A used maximum mean pressure (MMP) under the first metatarsal during a jump takeoff and only misclassified 1 female with no BSI. Model B used increased impulses under the hindfoot and second through fifth distal metatarsals while walking, and under the lesser toes during a cutting task, correctly categorizing 83.3% of male runners. Model C used higher medial midfoot peak pressure during a shuttle run and triad cumulative risk scores and correctly categorized 93.3% of runners who did not incur multiple BSIs and 66.7% of those who did. Model D included lower hindfoot impulses in the shuttle run and higher first metatarsal MMP during treadmill walking to correctly predict the subsequent occurrence of a foot BSI for 75% of women and 100% without.Conclusion: The models collectively suggested that higher plantar pressure may contribute to risk for BSI.

    View details for DOI 10.1177/23259671221104793

    View details for PubMedID 35734769

  • Evidence-Based Management of Medial Tibial Stress Syndrome in Runners CURRENT PHYSICAL MEDICINE AND REHABILITATION REPORTS Kuwabara, A., Dyrek, P., Olson, E., Kraus, E. 2021
  • Joint Level Analysis Of Mechanical Power During Drop Vertical Jumps In Youth Post ACL Reconstruction Morgan, J. J., Lyons, S. M., Chan, S. K., Shea, K. G., Kraus, E. A. LIPPINCOTT WILLIAMS & WILKINS. 2021: 145
  • Prevalence and Factors Associated with Bone Stress Injury in Middle School Runners. PM & R : the journal of injury, function, and rehabilitation Tenforde, A. S., DeLuca, S., Wu, A. C., Ackerman, K. E., Lewis, M., Rauh, M. J., Heiderscheit, B., Krabak, B. J., Kraus, E., Roberts, W., Troy, K. L., Barrack, M. T. 2021


    INTRODUCTION: Bone stress injury (BSI) in youth runners are clinically important during times of skeletal growth and are not well studied.OBJECTIVE: Evaluate the prevalence, anatomical distribution, and factors associated with running-related BSI in boy and girl middle school runners.DESIGN: Retrospective cross-sectional study.SETTING: Online survey distributed to middle school runners.METHODS: Survey evaluated BSI history, age, grade, height, weight, eating behaviors, menstrual function, exercise training, and other health characteristics.MAIN OUTCOME MEASUREMENTS: Prevalence and characteristics associated with history of BSI, stratified by cortical-rich (eg, tibia) and trabecular-rich (pelvis and femoral neck) locations.PARTICIPANTS: 2107 runners (n=1250 boys, n=857 girls), age 13.2±0.9y.RESULTS: One hundred-five (4.7%) runners reported a history of 132 BSIs, with higher prevalence in girls than boys (6.7% vs 3.8%, P=0.004). The most common location was the tibia (n=51). Most trabecular-rich BSIs (n=16, 94% total) were sustained by girls (pelvis: n=6; femoral neck: n=6; sacrum: n=4). In girls, consuming <3 daily meals (OR=18.5, 95%CI=7.3, 47.4), eating disorder (9.8, 95%CI=2.0, 47.0), family history of osteoporosis (OR=6.9, 95%CI=2.6, 18.0), and age (OR=1.6, 95%CI=1.0, 2.6) were associated with BSI. In boys, family history of osteoporosis (OR=3.2, 95%CI=1.2, 8.4), prior non-BSI fracture (OR=3.2, 95%CI=1.6, 6.7), and running mileage (OR=1.1, 95%CI=1.0, 1.1) were associated with BSI. Participating in soccer or basketball ≥2years was associated with lower odds of BSI for both sexes.CONCLUSION: While family history of osteoporosis and prior fracture (non-BSI) were most strongly related to BSI in the youth runners, behaviors contributing to an energy deficit, such as eating disorder and consuming<3 meals daily, also emerged as independent factors associated with BSI. While cross-sectional design limits determining causality, our findings suggest promoting optimal skeletal health through nutrition and participation in other sports including soccer and basketball may address factors associated with BSI in this population. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1002/pmrj.12673

    View details for PubMedID 34251763

  • 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

  • Narrative Review - Knee Pain in the Pediatric Athlete. Current reviews in musculoskeletal medicine Kuwabara, A., Kraus, E., Fredericson, M. 2021


    PURPOSE OF REVIEW: This review article seeks to highlight common youth athlete knee conditions due to overuse or trauma and elucidate differences from the adult populations.RECENT FINDINGS: Overuse conditions presented include apophysitis, osteochondritis dissecans plica syndrome, and discoid meniscus. Traumatic conditions presented include patellar instability, patellar sleeve fracture, and patellofemoral osteochondral fractures. Knee injuries affect a significant proportion of youth athletes. These injuries place athletes at higher risk of chronic pain and potentially osteoarthritis. We have reviewed common overuse and traumatic knee injuries and differentiating factors between the adult population to improve and expedite the diagnosis, treatment, and prognosis for youth athletes with knee injuries.

    View details for DOI 10.1007/s12178-021-09708-5

    View details for PubMedID 33818701

  • Dietary Supplement Use According to Sex and Triad Risk Factors in Collegiate Endurance Runners. Journal of strength and conditioning research Barrack, M., Fredericson, M., Dizon, F., Tenforde, A., Kim, B., Kraus, E., Kussman, A., Singh, S., Nattiv, A. 2020


    Barrack, MT, Fredericson, M, Dizon, F, Tenforde, AS, Kim, BY, Kraus, E, Kussman, A, Singh, S, and Nattiv, A. Dietary supplement use according to sex and Triad risk factors in collegiate endurance runners. J Strength Cond Res XX(X): 000-000, 2020-This cross-sectional study evaluated the prevalence in the use of dietary supplements among elite collegiate runners among 2 NCAA Division I cross-country teams. At the start of each season from 2015 to 2017, male and female endurance runners were recruited to complete baseline study measures; the final sample included 135 (male n = 65, female n = 70) runners. Runners completed a health survey, web-based nutrition survey, and Triad risk assessment. The prevalence of dietary supplement use and Triad risk factors, including disordered eating, low bone mass, amenorrhea (in women), low body mass index, and stress fracture history, was assessed. A total of 78.5% (n = 106) runners reported taking 1 or more supplements on ≥4 days per week over the past month, 48% (n = 65) reported use of ≥3 supplements. Products used with highest frequency included multivitamin/minerals 46.7% (n = 63), iron 46.7% (n = 63), vitamin D 34.1% (n = 46), and calcium 33.3% (n = 45). More women, compared with men, used iron (61.4 vs. 30.8%, p < 0.001) and calcium (41.4 vs. 24.6%, p = 0.04); men exhibited higher use of amino acids and beta-alanine (6.2 vs. 0%, p = 0.04). Runners with bone stress injury (BSI) history, vs. no previous BSI, reported more frequent use of ≥3 supplements (61.5 vs. 32.8%, p = 0.001), vitamin D (49.2 vs. 19.4%, p < 0.001), and calcium (47.7 vs. 19.4%, p = 0.001). Low bone mineral density was also associated with higher use of vitamin D and calcium. Most runners reported regular use of 1 or more supplements, with patterns of use varying based on sex, history of BSI, and bone mass.

    View details for DOI 10.1519/JSC.0000000000003848

    View details for PubMedID 33278271

  • Relationship Between Dynamic Limb Symmetry And Subjective Limb Confidence Post ACL Reconstruction In Youth Athletes Morgan, J. J., Lyons, S. M., Chan, S. K., Chan, C. M., Shea, K. G., Kraus, E. A. LIPPINCOTT WILLIAMS & WILKINS. 2020: 2–3
  • Dietary Intake Patterns And Risk Of Energy Deficiency In Ncaa Endurance Athletes Hernandez, C., Fredericson, M., Nattiv, A., Kraus, E., Kussman, A., Gravani, K., Miller, B., Papanos, L., Roche, M., Agans, D., Grohmann, E., Brotman, C., Barrack, M. LIPPINCOTT WILLIAMS & WILKINS. 2020: 753
  • Genetic Predictions Of Bone Mineral Density In Ultramarathon Runners: For Men, But Not For Women Miller, E. K., Fredericson, M., Roche, M., Skaggs, K., Hoeg, T., Sainani, K., Kraus, E. LIPPINCOTT WILLIAMS & WILKINS. 2020: 783–84
  • Food Accessibility And Eating Patterns In Elite Collegiate Endurance Runners Agans, D., Barrack, M., Fredericson, M., Kraus, E., Kussman, A., Gravani, K., Miller, B., Papanos, L., Roche, M., Hernandez, C., Grohmann, E., Brotman, C., Nattiv, A. LIPPINCOTT WILLIAMS & WILKINS. 2020: 757
  • Predictors And Prevalence Of Low Bone Mineral Density And Bone Stress Injuries In Ultramarathon Runners Hoeg, T. B., Fredericson, M., Sainani, K. L., Skaggs, K. F., Roche, M. D., Miller, E., Kraus, E. LIPPINCOTT WILLIAMS & WILKINS. 2020: 492
  • Identifying Triad Risk Factors In Ultramarathon Runners Skaggs, K. F., Fredericson, M., Miller, E. K., Roche, M., Hoeg, T. B., Sainani, K., Kraus, E. LIPPINCOTT WILLIAMS & WILKINS. 2020: 68
  • Youth running consensus statement: minimising risk of injury and illness in youth runners. British journal of sports medicine Krabak, B. J., Roberts, W. O., Tenforde, A. S., Ackerman, K. E., Adami, P. E., Baggish, A. L., Barrack, M. n., Cianca, J. n., D'Hemecourt, P. n., Fredericson, M. n., Goldman, J. T., Harrast, M. A., Heiderscheit, B. C., Hollander, K. n., Kraus, E. n., Luke, A. n., Miller, E. n., Moyer, M. n., Rauh, M. J., Toresdahl, B. G., Wasfy, M. M. 2020


    Despite the worldwide popularity of running as a sport for children, relatively little is known about its impact on injury and illness. Available studies have focused on adolescent athletes, but these findings may not be applicable to preadolescent and pubescent athletes. To date, there are no evidence or consensus-based guidelines identifying risk factors for injury and illness in youth runners, and current recommendations regarding suitable running distances for youth runners at different ages are opinion based. The International Committee Consensus Work Group convened to evaluate the current science, identify knowledge gaps, categorise risk factors for injury/illness and provide recommendations regarding training, nutrition and participation for youth runners.

    View details for DOI 10.1136/bjsports-2020-102518

    View details for PubMedID 33122252

  • Prevalence of Female Athlete Triad Risk Factors and Iron Supplementation Among High School Distance Runners: Results From a Triad Risk Screening Tool. Orthopaedic journal of sports medicine Skorseth, P. n., Segovia, N. n., Hastings, K. n., Kraus, E. n. 2020; 8 (10): 2325967120959725


    Investigations of the female athlete triad (Triad) in high school athletes have found that 36% had low energy availability, 54% had menstrual abnormalities, and 16% had low bone mineral density (BMD). Limited data are available showing the prevalence of these risk factors in high school distance runners or regarding best practice on screening for the Triad in the adolescent population.To (1) evaluate the prevalence of Triad risk factors and iron supplementation in high school distance runners and (2) pilot a screening tool for Triad risk score.Descriptive epidemiology study.The study population included female high school athletes who participated in cross-country/track. Participants completed a survey including questions regarding dietary habits, menstrual history, and bone stress injury (BSI) history. They then underwent evaluation of 25-hydroxyvitamin D, free triiodothyronine (T3), and dual-energy x-ray absorptiometry scan to measure body fat and BMD through use of age-, sex-, and ethnicity-matched Z scores. Triad scores were calculated. Relationships were analyzed using Spearman correlation coefficient.There were 38 study participants (mean age, 16.9 years). Average body mass index was 19.8 kg/m2. Disordered eating or eating disorders were reported in 76.3% of runners; in addition, 23.7% reported delayed menarche, 45.9% had a history of amenorrhea or oligomenorrhea, 42.1% had low BMD (Z score < -1.0), and 15.8% reported prior BSI. Low free T3 was significantly associated with higher Triad risk scores (rS = -0.36; P = .028). More than 42% of athletes were supplementing iron.The prevalence of Triad risk factors in high school distance runners was high. Free T3 was inversely associated with Triad score, which may serve as an indicator of low energy availability. Nearly half of the athletes were using iron supplementation.

    View details for DOI 10.1177/2325967120959725

    View details for PubMedID 33195716

    View details for PubMedCentralID PMC7605010

  • Impact of Adaptive Sports Participation on Quality of Life. Sports medicine and arthroscopy review Diaz, R., Miller, E. K., Kraus, E., Fredericson, M. 2019; 27 (2): 73–82


    The health benefits of regular recreational physical activity are well known in reducing secondary health consequences of a sedentary lifestyle in the general population. However, individuals with physical disabilities participate less frequently in recreational activity compared with those without disabilities. Although evidence on the impact of recreational physical activity on quality of life in this population is in its infancy, regular recreational and sports activity participation has shown to have a positive association with improvements in quality of life, life satisfaction, community reintegration, mood, and employment in those with disabilities. Facilitators of participating in adaptive sports include a desire to improve social support, physical fitness, health, and fun. Unfortunately, those with disabilities face numerous barriers to participate in adaptive sports including accessibility, transportation, awareness, finances, and physical and cognitive impairments. Further studies are needed to investigate facilitators and barriers to participating in adaptive sports to capitalize on the physical and psychosocial benefits of regular recreational activity. The aim of this article is to review the available literature on the effects of adaptive sports participation on quality of life.

    View details for DOI 10.1097/JSA.0000000000000242

    View details for PubMedID 31046012

  • Bone stress injuries in male distance runners: higher modified Female Athlete Triad Cumulative Risk Assessment scores predict increased rates of injury. British journal of sports medicine Kraus, E., Tenforde, A. S., Nattiv, A., Sainani, K. L., Kussman, A., Deakins-Roche, M., Singh, S., Kim, B. Y., Barrack, M. T., Fredericson, M. 2018


    OBJECTIVES: Bone stress injuries (BSI) are common in runners of both sexes. The purpose of this study was to determine if a modified Female Athlete Triad Cumulative Risk Assessment tool would predict BSI in male distance runners.METHODS: 156 male runners at two collegiate programmes were studied using mixed retrospective and prospective design for a total of 7years. Point values were assigned using risk assessment categories including low energy availability, low body mass index (BMI), low bone mineral density (BMD) and prior BSI. The outcome was subsequent development of BSI. Statistical models used a mixed effects Poisson regression model with p<0.05 as threshold for significance. Two regression analyses were performed: (1) baseline risk factors as the independent variable; and (2) annual change in risk factors (longitudinal data) as the independent variable.RESULTS: 42/156 runners (27%) sustained 61 BSIs over an average 1.9 years of follow-up. In the baseline risk factor model, each 1 point increase in prior BSI score was associated with a 57% increased risk for prospective BSI (p=0.0042) and each 1 point increase in cumulative risk score was associated with a 37% increase in prospective BSI risk (p=0.0079). In the longitudinal model, each 1 point increase in cumulative risk score was associated with a 27% increase in prospective BSI risk (p=0.05). BMI (rate ratio (RR)=1.91, p=0.11) and BMD (RR=1.58, p=0.19) risk scores were not associated with BSI.CONCLUSION: A modified cumulative risk assessment tool may help identify male runners at elevated risk for BSI. Identifying risk factors may guide treatment and prevention strategies.

    View details for PubMedID 30580252

  • Corrigendum to "A little bit faster: Lower extremity joint kinematics and kinetics as recreational runners achieve faster speeds" [J. Biomech. 71 (2018) 167-175]. Journal of biomechanics Orendurff, M. S., Kobayashi, T., Tulchin-Francis, K., Tullock, A. M., Villarosa, C., Chan, C., Kraus, E., Strike, S. 2018

    View details for PubMedID 30442429

  • Team Approach: Bone Health in Children and Adolescents. JBJS reviews Kraus, E., Bachrach, L. K., Grover, M. 2018

    View details for PubMedID 30325758

  • Utilization And Efficacy Of The "Run Fueled" Smart-phone Application Among Collegiate Endurance Runners Barrack, M., Fredericson, M., Kraus, E., Kim, B., Singh, S., Gravani, K., Miller, B., Nativ, A. LIPPINCOTT WILLIAMS & WILKINS. 2018: 82
  • A Review and Proposed Rationale for the use of Ultrasonography as a Diagnostic Modality in the Identification of Bone Stress Injuries. Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine Fukushima, Y., Ray, J., Kraus, E., Syrop, I. P., Fredericson, M. 2018


    Bone stress injuries are common in military personnel and athletes. The delayed diagnosis of a bone stress injury can lead to a more severe injury that requires a longer period of treatment. The early detection of bone stress injuries is a central part of management. Currently, the reference standard for detecting bone stress injuries is magnetic resonance imaging. However, the expanding use of point-of-care ultrasonography (US) may enable the early detection of bone stress injuries in the clinical setting. In this article, we review the US detection of bone stress injuries, as well as discuss the rationale for the use of US in the diagnosis of these injuries.

    View details for PubMedID 29655254

  • Nutrition Goals Prioritized By Elite Endurance Runners Undergoing A Nutrition Education Intervention Barrack, M., Fredericson, M., Adam, T. S., Kraus, E., Kim, B., Singh, S., Kussman, A., Gravani, K., Ansari, Y., Miller, B., Nattiv, A. LIPPINCOTT WILLIAMS & WILKINS. 2017: 852
  • Preliminary Results from a Prospective Study Using the Female Athlete Triad Cumulative Risk Assessment Kraus, E., Nattiv, A., Tenforde, A., Kussman, A., Barrack, M., Kim, B., Deakins-Roche, M., Mistra, N., Singh, S., Fredericson, M. LIPPINCOTT WILLIAMS & WILKINS. 2017: 1098
  • Integrating Musculoskeletal Education and Patient Care at Medical Student-Run Free Clinics. PM & R : the journal of injury, function, and rehabilitation McQuillan, T., Wilcox-Fogel, N., Kraus, E., Ladd, A., Fredericson, M. 2017


    Student-run free clinics (SRFCs) have emerged as an important educational component of United States (US) medical schools. Despite the prevalence of musculoskeletal (MSK) problems presenting to SRFCs, students and clinics are often unprepared to diagnose and to treat common MSK complaints.We sought to determine the scope of diagnosis and treatment at a medical student-run free clinic specializing in musculoskeletal care using physical medicine and rehabilitation (PM&R) residents. Secondary goals included reviewing student satisfaction and determining the appropriateness of the clinic in medical education.Retrospective chart review, anonymous online survey.Primary care, free student clinic affiliated with tertiary academic medical center.A total of 20 medical student volunteers, 6 PM&R residents, and 91 community patients.We established a musculoskeletal clinic as a specialty referral clinic for the 2 primary care SRFCs with institutional support from a partner medical school. We then reviewed clinical operations retrospectively using electronic medical records and student satisfaction based on an online survey.We analyzed patient demographics and chief complaints, referrals provided, and medical services rendered. We also used a 5-point Likert scale to assess student satisfaction.A monthly musculoskeletal referral clinic was established with the oversight of PM&R attendings and residents. The clinic received 91 referrals and managed 61 unique patients over a 2.5-year study period. The most common presentations to the clinic involved knee pain (n = 17, 27.9%) and back pain (n = 16, 26.2%). Pro bono relationships with community and institutional partners enabled all patients to receive medical examinations, physical therapy visits, plain film radiographs, and insurance consultations free of charge. Student satisfaction with teaching and patient care was high, with 19 of 20 students reporting their experience as "good" or "excellent."SRFCs represent an underused opportunity to enhance MSK education among medical students by treating a variety of common MSK complaints in an underserved population.To be determined.

    View details for DOI 10.1016/j.pmrj.2017.03.008

    View details for PubMedID 28389399

  • Poster 155 Higher Cumulative Risk Assessment Scores Are Associated with Delayed Return to Play in Division I Collegiate Distance Runners. PM & R : the journal of injury, function, and rehabilitation Kraus, E. A., Kim, B., Nattiv, A., Tenforde, A., Barrack, M., Deakins-Roche, M., Kussman, A., Singh, S., Morkos, J., Fredericson, M. 2016; 8 (9S): S212-S213

    View details for DOI 10.1016/j.pmrj.2016.07.196

    View details for PubMedID 27672919

  • Piriformis Syndrome With Variant Sciatic Nerve Anatomy: A Case Report. PM & R : the journal of injury, function, and rehabilitation Kraus, E., Tenforde, A. S., Beaulieu, C. F., Ratliff, J., Fredericson, M. 2016; 8 (2): 176-179


    A 68-year-old male long distance runner presented with low back and left buttock pain, which eventually progressed to severe and debilitating pain, intermittently radiating to the posterior thigh and foot. A comprehensive workup ruled out possible spine or hip causes of his symptoms. A pelvic magnetic resonance imaging neurogram with complex oblique planes through the piriformis demonstrated variant anatomy of the left sciatic nerve consistent with the clinical diagnosis of piriformis syndrome. The patient ultimately underwent neurolysis with release of the sciatic nerve and partial resection of the piriformis muscle. After surgery the patient reported significant pain reduction and resumed running 3 months later. Piriformis syndrome is uncommon but should be considered in the differential diagnosis for buttock pain. Advanced imaging was essential to guide management.

    View details for DOI 10.1016/j.pmrj.2015.09.005

    View details for PubMedID 26377629

  • Bone Stress Injuries in Runners. Physical medicine and rehabilitation clinics of North America Tenforde, A. S., Kraus, E., Fredericson, M. 2016; 27 (1): 139-149


    Bone stress injuries (BSIs) are common running injuries and may occur at a rate of 20% annually. Both biological and biomechanical risk factors contribute to BSI. Evaluation of a runner with suspected BSI includes completing an appropriate history and physical examination. MRI grading classification for BSI has been proposed and may guide return to play. Management includes activity modification, optimizing nutrition, and addressing risk factors, including the female athlete triad. BSI prevention strategies include screening for risk factors during preparticipation evaluations, optimizing nutrition (including adequate caloric intake, calcium, and vitamin D), and promoting ball sports during childhood and adolescence.

    View details for DOI 10.1016/j.pmr.2015.08.008

    View details for PubMedID 26616181