Impact of acute dietary and exercise manipulation on next day RMR measurements and DXA body composition estimates.

PURPOSE: To investigate the effects of acute diet and exercise manipulation on resting metabolic rate (RMR) measurement variability and dual energy x-ray absorptiometry (DXA) body composition estimates. METHODS: 10 male and 10 female endurance athletes (12 cyclists, 5 triathletes, 4 runners) of Tier 2 (n = 18) to Tier 3 (n = 2) calibre underwent five conditions using a Latin square counterbalance design. For 24 hours, athletes consumed a diet providing excessive energy availability (75 kcal‧kg fat free mass (FFM) -1 ) without exercise (GEA rest ), high energy availability (45 kcal‧kg FFM -1 ) without (HEA rest ) or with exercise (HEA ex ), or low-energy availability (15 kcal‧kg FFM -1 ) without (LEA rest ) or with exercise (LEA ex ). Exercise involved two bouts of cycling (morning bout: 149 ± 34 min at 55% of maximal aerobic capacity (VO 2 max); afternoon bout: 60 min at 65% of VO 2 max) that resulted in a cumulative exercise energy expenditure of 30 kcal‧kg FFM -1 . The following day, RMR and DXA measurements occurred after a 10-hour fast and 12-hours post-exercise. RESULTS: There were no sex differences in relative RMR ( p = 0.158) nor effects of any of the five conditions on RMR ( p = 0.358). For both male and female athletes, FFM estimates were decreased following the LEA rest (-0.84 ± 0.66 kg; p = 0.001) and LEA ex (-0.65 ± 0.86 kg; p = 0.016) conditions compared to the GEA rest condition and following the LEA rest (-0.73 ± 0.51 kg; p = 0.001) and LEA ex (-0.54 ± 0.79 kg; p = 0.024) conditions compared to the HEA ex condition. There was no effect of condition on fat mass estimates ( p = 0.819). CONCLUSION: Acute periods of diet and exercise manipulation did not create artifacts in next-day RMR measurements. However, as changes in estimates of FFM were seen, diet and exercise should be controlled in the 24-hours prior to DXA scans.

Athletic Identity Associations in Young Sports Medicine Patients.

INTRODUCTION: Few studies have assessed athletic identity levels in young patients. This study examined athletic identity in adolescents and explored associations between athletic identity, patterns of sport participation, and coping skills. METHODS: Patients aged 12 to 18 years who received sports medicine care completed a one-time, voluntary, anonymous survey. Surveys included demographics, sport participation information, Athletic Identity Measurement Scale (AIMS), and Athletic Coping Skills Inventory (ACSI). Statistical analysis included Fisher exact test, Student t test, Wilcoxon rank sum test, Kruskal-Wallis test, and Pearson correlation. RESULTS: Three hundred thirty-four patients (mean ± SD age 15.0 ± 1.8 years, 64.7% girls) completed questionnaires. The mean AIMS and ACSI scores were 45.2 ± 11.5 and 50.2 ± 10.9, respectively. No notable differences were observed in AIMS scores between age groups or sexes. An increase in mean AIMS scores (higher athletic identity) was seen with greater weekly hours of sport participation (P < 0.001) and months per year of primary sport participation (P < 0.001). Multisport per season athletes had higher AIMS scores than single-sport athletes (48.2 ± 10.1 vs. 43.0 ± 11.9, P < 0.001). Team sport athletes reported higher athletic identities than individual sport athletes (47.0 ± 10.7, 41.4 ± 11.4, P < 0.001). Athletic Identity Measurement Scale scores positively correlated with ACSI scores (r = 0.31, P < 0.0001). Athletes with the highest athletic identity had markedly higher scores on ACSI subscales of Coachability, Concentration, Confidence and Achievement Motivation, Goal Setting and Mental Preparation, and Peaking Under Pressure than athletes with the least athletic identity. However, those with the highest athletic identities reported significantly lower scores on the ACSI Freedom From Worry subscale (P < 0.001). DISCUSSION: Athletic identity did not differ among adolescents by age or sex. Athletic identity was higher in team sport athletes and those with increased sport participation volumes. While high athletic identity was associated with higher scores on favorable coping skill dimensions, these athletes may also worry more, potentially placing them at greater psychological risk after injury.

The Temporal Effects of Altitude and Low Energy Availability Manipulation on Resting Metabolic Rate in Female Race Walkers.

PURPOSE: To investigate the temporal effects of ~1,800 m altitude exposure and energy availability (EA) manipulation on resting metabolic rate (RMR). METHODS: Twenty elite female race walkers underwent a 3-week training camp at an altitude of ~1,800 m. During the first two weeks, athletes consumed a high EA (HEA) diet of 45 kcal·kg fat free mass (FFM) -1 ·day -1 . During the final week, half the athletes consumed a low EA (LEA) diet of 15 kcal·kg FFM -1 ·day -1 while the others continued on a HEA diet. Athletes followed individualized training plans throughout the study. To assess the effect of altitude on RMR, athletes in the HEA group had RMR measured at baseline (~580 m) prior to altitude exposure (Pre-alt), at 36-hours (36 h-alt), 2 weeks (Wk2-alt) and 3 weeks into altitude exposure (Wk3-alt), and at 36 hours post-altitude exposure at ~580 m (36 h-post). To assess the effect of LEA exposure on RMR while at altitude, athletes in the LEA group underwent RMR measurements at Pre-alt and before (Wk2-alt) and after the 7-days of LEA (Wk3-alt). RESULTS: Compared to Pre-alt, the RMR of HEA athletes was increased at 36 h-alt (+5.3 ± 3.1%; p = 0.026) and Wk2-alt (+4.9 ± 4.9%; p = 0.049), but was no longer elevated at Wk3-alt (+1.7 ± 4.2%; p = 0.850). The RMR of HEA athletes at 36 h-post was lower than all timepoints at altitude (p < 0.05) but was not different from Pre-alt (-3.9 ± 7.2%; p = 0.124). The 7-day period of LEA exposure at altitude did not affect RMR (p = 0.347). CONCLUSIONS: RMR was transiently increased with ~1,800 m altitude exposure in female athletes and was unaffected by short-term LEA. However, the altitude-induced increase was small (~25-75 kcal/day) and was unlikely to have clinically significant implications for daily energy requirements.

Beach Sprints Rowing: Injury and Illness Prevalence at the 2022 World Championships.

Background: Injury and illness surveillance helps establish the infrastructure to provide adequate medical support at regattas and is the foundation for developing prevention strategies. Objectives: To assess the prevalence and characteristics of injuries in the 4 weeks before the start of the 2022 World Rowing Beach Sprints Finals (WRBSF) (the 'Prevalence Survey') and describe the incidence and nature of new-onset injuries and illnesses incurred during the WRBSF (the 'Incidence Survey'). Methods: Athletes completed: (1) a prevalence survey recording injuries the 4 weeks before the WRBSF and (2) a recording of injuries and illnesses that occurred during the 3-day regatta. Results: Fifty-nine of 152 eligible WRBSF athletes completed the prevalence injury survey. Twenty-three (38.9%) reported experiencing at least one injury within the 4 weeks before the WRBSF. The most prevalent anatomical injury sites were the forearm (11.86%), lumbar spine (10.17%), knee (8.47%), ankle (6.78%) and hand/fingers (6.78%). During the competition, only two illness occurrences were reported; both were respiratory infections. Two athletes reported injuries: a hamstring strain and a concussion. Conclusion: Rowers presenting to the WRBSF described injuries leading up to the event that were similar to those common in classic rowing. Rowers at the event suffered injuries of the lower limb that were different from classic rowing and may be related to the addition of running to this event. An event concussion should be considered as a more likely injury in this type of rowing and future events should be prepared to manage such an injury.

Application of the IOC Relative Energy Deficiency in Sport (REDs) Clinical Assessment Tool version 2 (CAT2) across 200+ elite athletes.

OBJECTIVE: This cross-sectional retrospective and prospective study implemented the 2023 International Olympic Committee Relative Energy Deficiency in Sport (REDs) Clinical Assessment Tool version 2 (CAT2) to determine the current severity of REDs (primary outcome) and future risk of bone stress injuries (BSI, exploratory outcome) in elite athletes. METHODS: Female (n=143; 23.3±4.3 years) and male (n=70; 23.1±3.7 years) athletes (performance tier 3 (52%), tier 4 (36%), tier 5 (12%)) participated in a baseline CAT2 (with minor modifications) assessment, including a self-report questionnaire (menstrual function (females), BSI, Eating Disorder Examination Questionnaire (EDE-Q)), bone mineral density (BMD via DXA) and fasted blood analysis (triiodothyronine (T3), testosterone, cholesterol). Athletes were assigned a green, yellow, orange or red light via CAT2. The prospective risk of new self-report of physician-diagnosed BSI was assessed over a subsequent 6-24 months. RESULTS: REDs prevalence was 55% green, 36% yellow, 5% orange and 4% red light. The CAT2 identified a greater prevalence of amenorrhoea and BSI and lower T3, testosterone and BMD (p<0.01) in red, orange and yellow (those with REDs) versus green light. ORs for a prospective self-reported BSI (majority physician diagnosed) were greater in orange vs green (OR 7.71, 95% CI (1.26 to 39.83)), in females with severe amenorrhoea (OR 4.6 (95% CI 0.98 to 17.85)), in males with low sex drive (OR 16.0 (95% CI 4.79 to 1038.87)), and athletes with elevated EDE-Q global scores (OR 1.45 (95% CI 0.97 to 1.97)). CONCLUSION: The CAT2 has high validity in demonstrating current severity of REDs, with increased future risk of self-reported BSI in athletes with a more severe REDs traffic light category.

Centering the female athlete voice in a sports science research agenda: a modified Delphi survey with Team USA athletes.

OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Beyond Menstrual Dysfunction: Does Altered Endocrine Function Caused by Problematic Low Energy Availability Impair Health and Sports Performance in Female Athletes?

Low energy availability, particularly when problematic (i.e., prolonged and/or severe), has numerous negative consequences for health and sports performance as characterized in relative energy deficiency in sport. These consequences may be driven by disturbances in endocrine function, although scientific evidence clearly linking endocrine dysfunction to decreased sports performance and blunted or diminished training adaptations is limited. We describe how low energy availability-induced changes in sex hormones manifest as menstrual dysfunction and accompanying hormonal dysfunction in other endocrine axes that lead to adverse health outcomes, including negative bone health, impaired metabolic activity, undesired outcomes for body composition, altered immune response, problematic cardiovascular outcomes, iron deficiency, as well as impaired endurance performance and force production, all of which ultimately may influence athlete health and performance. Where identifiable menstrual dysfunction indicates hypothalamic-pituitary-ovarian axis dysfunction, concomitant disturbances in other hormonal axes and their impact on the athlete's health and sports performance must be recognized as well. Given that the margin between podium positions and "losing" in competitive sports can be very small, several important questions regarding low energy availability, endocrinology, and the mechanisms behind impaired training adaptations and sports performance have yet to be explored.

Minimal influence of the menstrual cycle or hormonal contraceptives on performance in female rugby league athletes.

We examined performance across one menstrual cycle (MC) and 3 weeks of hormonal contraceptives (HC) use to identify whether known fluctuations in estrogen and progesterone/progestin are associated with functional performance changes. National Rugby League Indigenous Women's Academy athletes [n = 11 naturally menstruating (NM), n = 13 using HC] completed performance tests [countermovement jump (CMJ), squat jump (SJ), isometric mid-thigh pull, 20 m sprint, power pass and Stroop test] during three phases of a MC or three weeks of HC usage, confirmed through ovulation tests alongside serum estrogen and progesterone concentrations. MC phase or HC use did not influence jump height, peak force, sprint time, distance thrown or Stroop effect. However, there were small variations in kinetic and kinematic CMJ/SJ outputs. NM athletes produced greater mean concentric power in MC phase four than one [+0.41 W·kg-1 (+16.8%), p = 0.021] during the CMJ, alongside greater impulse at 50 ms at phase one than four [+1.7 N·s (+4.7%), p = 0.031] during the SJ, without differences between tests for HC users. Among NM athletes, estradiol negatively correlated with mean velocity and power (r = -0.44 to -0.50, p < 0.047), progesterone positively correlated with contraction time (r = 0.45, p = 0.045), and both negatively correlated with the rate of force development and impulse (r = -0.45 to -0.64, p < 0.043) during the SJ. During the CMJ, estradiol positively correlated to 200 ms impulse (r = 0.45, p = 0.049) and progesterone to mean power (r = 0.51, p = 0.021). Evidence of changes in testing performance across a MC, or during active HC use, is insufficient to justify "phase-based testing"; however, kinetic or kinematic outputs may be altered in NM athletes.

Factors Associated With High-Risk and Low-Risk Bone Stress Injury in Female Runners: Implications for Risk Factor Stratification and Management.

Background: Bone stress injury (BSI) is a common overuse injury in active women. BSIs can be classified as high-risk (pelvis, sacrum, and femoral neck) or low-risk (tibia, fibula, and metatarsals). Risk factors for BSI include low energy availability, menstrual dysfunction, and poor bone health. Higher vertical load rates during running have been observed in women with a history of BSI. Purpose/Hypothesis: The purpose of this study was to characterize factors associated with BSI in a population of premenopausal women, comparing those with a history of high-risk or low-risk BSI with those with no history of BSI. It was hypothesized that women with a history of high-risk BSI would be more likely to exhibit lower bone mineral density (BMD) and related factors and less favorable bone microarchitecture compared with women with a history of low-risk BSI. In contrast, women with a history of low-risk BSI would have higher load rates. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Enrolled were 15 women with a history of high-risk BSI, 15 with a history of low-risk BSI, and 15 with no history of BSI. BMD for the whole body, hip, and spine was standardized using z scores on dual-energy x-ray absorptiometry. High-resolution peripheral quantitative computed tomography was used to quantify bone microarchitecture at the radius and distal tibia. Participants completed surveys characterizing factors that influence bone health-including sleep, menstrual history, and eating behaviors-utilizing the Eating Disorder Examination Questionnaire (EDE-Q). Each participant completed a biomechanical assessment using an instrumented treadmill to measure load rates before and after a run to exertion. Results: Women with a history of high-risk BSI had lower spine z scores than those with low-risk BSI (-1.04 ± 0.76 vs -0.01 ± 1.15; P < .05). Women with a history of high-risk BSI, compared with low-risk BSI and no BSI, had the highest EDE-Q subscores for Shape Concern (1.46 ± 1.28 vs 0.76 ± 0.78 and 0.43 ± 0.43) and Eating Concern (0.55 ± 0.75 vs 0.16 ± 0.38 and 0.11 ± 0.21), as well as the greatest difference between minimum and maximum weight at current height (11.3 ± 5.4 vs 7.7 ± 2.9 and 7.6 ± 3.3 kg) (P < .05 for all). Women with a history of high-risk BSI were more likely than those with no history of BSI to sleep <7 hours on average per night during the week (80% vs 33.3%; P < .05). The mean and instantaneous vertical load rates were not different between groups. Conclusion: Women with a history of high-risk BSI were more likely to exhibit risk factors for poor bone health, including lower BMD, while load rates did not distinguish women with a history of BSI.

Effect of Menstrual Cycle Phase and Hormonal Contraceptives on Resting Metabolic Rate and Body Composition.

The cyclical changes in sex hormones across the menstrual cycle (MC) are associated with various biological changes that may alter resting metabolic rate (RMR) and body composition estimates. Hormonal contraceptive (HC) use must also be considered given their impact on endogenous sex hormone concentrations and synchronous exogenous profiles. The purpose of this study was to determine if RMR and dual-energy X-ray absorptiometry body composition estimates change across the MC and differ compared with HC users. This was accomplished during a 5-week training camp involving naturally cycling athletes (n = 11) and HC users (n = 7 subdermal progestin implant, n = 4 combined monophasic oral contraceptive pill, n = 1 injection) from the National Rugby League Indigenous Women's Academy. MC phase was retrospectively confirmed via serum estradiol and progesterone concentrations and a positive ovulation test. HC users had serum estradiol and progesterone concentrations assessed at the time point of testing. Results were analyzed using general linear mixed model. There was no effect of MC phase on absolute RMR (p = .877), relative RMR (p = .957), or dual-energy X-ray absorptiometry body composition estimates (p > .05). There was no effect of HC use on absolute RMR (p = .069), relative RMR (p = .679), or fat mass estimates (p = .766), but HC users had a greater fat-free mass and lean body mass than naturally cycling athletes (p = .028). Our findings suggest that RMR and dual-energy X-ray absorptiometry body composition estimates do not significantly differ due to changes in sex hormones in a group of athletes, and measurements can be compared between MC phases or with HC usage without variations in sex hormones causing additional noise.

Female Athlete Research Camp: A Unique Model for Conducting Research in High-Performance Female Athletes.

PURPOSE: The purpose of this study is to describe the implementation of a novel research protocol for conducting research with highly trained female athletes, including characterizing menstrual cycle (MC) function, hormonal profiles and symptoms of the participating athletes. METHODS: Twenty-four Australian First Nation female Rugby League athletes completed this study, which involved 11 wk of cycle tracking, followed by attendance at a 5-wk training camp. Throughout the study, athletes completed a daily survey, reporting their MC function and any associated symptoms. During the training camp, athletes reported to the laboratory on three occasions and provided a venous blood sample, which was analyzed for reproductive hormones. For naturally cycling athletes (athleteNC, n = 11), this included phase 1, 2, and 4 of the menstrual cycle, whereas athletes using hormonal contraception (athleteHC; n = 13) were tested at three equally spaced time points in which consistent exogenous hormone provision occurred. RESULTS: In the athleteNC cohort, just one athlete reached criteria for classification as eumenorrheic, with five athletes showing evidence of MC dysfunction. The prevalence of symptoms on any given day was similar between athleteNC (33.7%) and athleteHC (22.9%; P = 0.376); however, more symptoms were reported in athleteNC, suggesting that they were more likely to report multiple symptoms. Regardless of MC function, there was a significant, positive association between bleeding and symptoms ( P < 0.001), where athletes were more likely to report one or more symptoms on bleeding (50.1%) compared with nonbleeding days (22.0%). CONCLUSIONS: We describe an innovative strategy to investigate the effect of MC function and MC phase in a high-performance sport environment, including approaches to address the challenges of undertaking research with female athletes with MC variability and those using exogenous hormonal therapies.

Differences in Knowledge of Female Athlete Triad and Relative Energy Deficiency in Sport in Female Cross-Country Athletes.

BACKGROUND: Female Athlete Triad (Triad) and Relative Energy Deficiency in Sport (REDs) describe potential health and performance consequences of low energy availability. OBJECTIVE: We surveyed female cross-country athletes to assess differences in educational impact scores (knowledge score * confidence score factor, EIS) of Triad and REDs. Associations between EIS and participant characteristics [e.g., mileage (current and peak), years of running experience, age, bone stress injury history, division level participation, academic area of study, Triad or REDs diagnoses, and Triad or REDs education] were explored. MATERIALS & METHODS: An evidence-based online survey was developed and administered via Qualtrics™ to female collegiate cross-country athletes (n = 275; age = 20 ± 1 yrs). RESULTS: There was a weak correlation between peak career mileage and EIS (r = 0.195; p = 0.010). EIS significantly differed in athletes with a related academic area of study vs. those without (21.91 ± 5.16, 16.11 ± 5.54, respectively). EIS significantly differed in athletes with Triad and REDs diagnoses (21.69 ± 5.85 and 22.58 ± 6.82, respectively) vs. those without (16.80 ± 6.54 and 17.20 ± 6.34, respectively). EIS was higher in those who had received Triad education vs. those who had not (21.03 ± 6.86, 18.12 ± 6.82, respectively). A significant interaction between peak career mileage and Triad diagnosis was found (p = 0.005). CONCLUSIONS: Significant education-based and diagnoses differences suggests that Triad diagnoses correlate with peak career mileage. These findings support education to improve not only treatment, but prevention, of Triad and REDs.

Clinical assessment, treatment, and referral trends for adolescent runners seeking care at an injured runners' clinic.

PURPOSE: Over a 10-year time frame, this study aimed to evaluate diagnosis, treatment, and referral trends for adolescent runners seeking care for running-related injuries (RRIs) at a clinic that specializes in running medicine. METHODS: This study was a retrospective chart review of 392 adolescent runners (2,326 encounters) who sought care for RRIs between the years 2011 and 2021. Descriptive statistics were used to summarize clinical assessments, referrals, assistive devices, and medications prescribed or administered overall and by injury type. Chi-square analyses were used to compare proportions of services rendered across the 10-year time frame. RESULTS: Patients most frequently received manual evaluations or special tests during clinic visits. Most visits resulted in at least one referral (91%), primarily for physical therapy or gait-training. Assistive devices and medications/supplements were offered at only 18% of patient visits. The majority of assessments (X2 = 69.7, p = 0.002), treatments (X2: 23.6-43.8, p: <  0.001-0.003), and referrals (X2 = 132, p <  0.001) were for shin injuries. Larger proportions of nutrition assessments (X2 = 40.7, p <  0.001), interventions (X2 = 26.8, p = 0.003), and referrals (X2 = 27.5, p = 0.002) were performed in or after the year 2015. CONCLUSION: Clinic visits for shin injuries required the most clinical resources per episode of care. There were observed shifts in clinical assessment and treatment approaches to include more expanded nutritional and physiologic considerations.

Effect of menstrual cycle and contraceptive pill phase on aspects of exercise physiology and athletic performance in female athletes: protocol for the Feminae international multisite innovative project.

The idiom 'more high-quality research is needed' has become the slogan for sport and exercise physiology-based research in female athletes. However, in most instances, it is challenging to address this gap of high-quality research in elite female athletes at a single study site due to challenges in recruiting enough participants with numerous menstrual cycle and contraceptive pill permutations. Accordingly, we have assembled an international multisite team to undertake an innovative project for female athletes, which investigates the effects of changes in endogenous and exogenous oestrogen and progesterone/progestins across the menstrual cycle and in response to second-generation combined monophasic contraceptive pill use, on aspects of exercise physiology and athletic performance. This project will employ the current gold-standard methodologies in this area, resulting in an adequately powered dataset. This protocol paper describes the consortium-based approach we will undertake during this study.

Feminae: an international multisite innovative project for female athletes.

Sufficient high-quality studies in sport science using women as participants are lacking, meaning that our knowledge and understanding of female athletes in relation to their ovarian hormone profiles is limited. Consortia can be used to pool talent, expertise and data, thus accelerating our learning on a given topic and reducing research waste through collaboration. To this end, we have assembled an international multisite team, described here, to investigate the effects of the menstrual cycle and contraceptive pill phase on aspects of exercise physiology and sports performance in female athletes. We intend to produce an adequately powered, high-quality dataset, which can be used to inform the practices of female athletes. Our approach will also employ research transparency-through the inclusion of a process evaluation-and reproducibility-through a standardised study protocol.

Review of the scientific rationale, development and validation of the International Olympic Committee Relative Energy Deficiency in Sport Clinical Assessment Tool: V.2 (IOC REDs CAT2)-by a subgroup of the IOC consensus on REDs.

Relative Energy Deficiency in Sport (REDs) has various different risk factors, numerous signs and symptoms and is heavily influenced by one's environment. Accordingly, there is no singular validated diagnostic test. This 2023 International Olympic Committee's REDs Clinical Assessment Tool-V.2 (IOC REDs CAT2) implements a three-step process of: (1) initial screening; (2) severity/risk stratification based on any identified REDs signs/symptoms (primary and secondary indicators) and (3) a physician-led final diagnosis and treatment plan developed with the athlete, coach and their entire health and performance team. The CAT2 also introduces a more clinically nuanced four-level traffic-light (green, yellow, orange and red) severity/risk stratification with associated sport participation guidelines. Various REDs primary and secondary indicators have been identified and 'weighted' in terms of scientific support, clinical severity/risk and methodological validity and usability, allowing for objective scoring of athletes based on the presence or absence of each indicator. Early draft versions of the CAT2 were developed with associated athlete-testing, feedback and refinement, followed by REDs expert validation via voting statements (ie, online questionnaire to assess agreement on each indicator). Physician and practitioner validity and usability assessments were also implemented. The aim of the IOC REDs CAT2 is to assist qualified clinical professionals in the early and accurate diagnosis of REDs, with an appropriate clinical severity and risk assessment, in order to protect athlete health and prevent prolonged and irreversible outcomes of REDs.

Primary, secondary and tertiary prevention of Relative Energy Deficiency in Sport (REDs): a narrative review by a subgroup of the IOC consensus on REDs.

Relative Energy Deficiency in Sport (REDs) is common among female and male athletes representing various sports at different performance levels, and the underlying cause is problematic low energy availability (LEA). It is essential to prevent problematic LEA to decrease the risk of serious health and performance consequences. This narrative review addresses REDs primary, secondary and tertiary prevention strategies and recommends best practice prevention guidelines targeting the athlete health and performance team, athlete entourage (eg, coaches, parents, managers) and sport organisations. Primary prevention of REDs seeks to minimise exposure to and reduce behaviours associated with problematic LEA. Some of the important strategies are educational initiatives and de-emphasising body weight and leanness, particularly in young and subelite athletes. Secondary prevention encourages the early identification and management of REDs signs or symptoms to facilitate early treatment to prevent development of more serious REDs outcomes. Recommended strategies for identifying athletes at risk are self-reported screening instruments, individual health interviews and/or objective assessment of REDs markers. Tertiary prevention (clinical treatment) seeks to limit short-term and long-term severe health consequences of REDs. The cornerstone of tertiary prevention is identifying the source of and treating problematic LEA. Best practice guidelines to prevent REDs and related consequences include a multipronged approach targeting the athlete health and performance team, the athlete entourage and sport organisations, who all need to ensure a supportive and safe sporting environment, have sufficient REDs knowledge and remain observant for the early signs and symptoms of REDs.

Mapping the complexities of Relative Energy Deficiency in Sport (REDs): development of a physiological model by a subgroup of the International Olympic Committee (IOC) Consensus on REDs.

The 2023 International Olympic Committee (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs) notes that exposure to low energy availability (LEA) exists on a continuum between adaptable and problematic LEA, with a range of potential effects on both health and performance. However, there is variability in the outcomes of LEA exposure between and among individuals as well as the specific manifestations of REDs. We outline a framework for a 'systems biology' examination of the effect of LEA on individual body systems, with the eventual goal of creating an integrated map of body system interactions. We provide a template that systematically identifies characteristics of LEA exposure (eg, magnitude, duration, origin) and a variety of moderating factors (eg, medical history, diet and training characteristics) that could exacerbate or attenuate the type and severity of impairments to health and performance faced by an individual athlete. The REDs Physiological Model may assist the diagnosis of underlying causes of problems associated with LEA, with a personalised and nuanced treatment plan promoting compliance and treatment efficacy. It could also be used in the strategic prevention of REDs by drawing attention to scenarios of LEA in which impairments of health and performance are most likely, based on knowledge of the characteristics of the LEA exposure or moderating factors that may increase the risk of harmful outcomes. We challenge researchers and practitioners to create a unifying and dynamic physiological model for each body system that can be continuously updated and mapped as knowledge is gained.