Athletic amenorrhea: energy deficit or psychogenic challenge?

Agreement Between Heart Rate Variability - Derived vs. Ventilatory and Lactate Thresholds: A Systematic Review with Meta-Analyses

BACKGROUND

Determining thresholds by measuring blood lactate levels (lactate thresholds) or gas exchange (ventilatory thresholds) that delineate the different exercise intensity domains is crucial for training prescription. This systematic review with meta-analyses aims to assess the overall validity of the first and second heart rate variability - derived threshold (HRVT1 and HRVT2, respectively) by computing global effect sizes for agreement and correlation between HRVTs and reference - lactate and ventilatory (LT-VTs) - thresholds. Furthermore, this review aims to assess the impact of subjects' characteristics, HRV methods, and study protocols on the agreement and correlation between LT-VTs and HRVTs.

METHODS

Systematic computerised searches for studies determining HRVTs during incremental exercise in humans were conducted. The agreements and correlations meta-analyses were conducted using a random-effect model. Causes of heterogeneity were explored by subgroup analysis and meta-regression with subjects' characteristics, incremental exercise protocols, and HRV methods variables. The methodological quality was assessed using QUADAS-2 and STARDHRV tools. The risk of bias was assessed by funnel plots, fail-safe N test, Egger's test of the intercept, and the Begg and Mazumdar rank correlation test.

RESULTS

Fifty included studies (1160 subjects) assessed 314 agreements (95 for HRVT1, 219 for HRVT2) and 246 correlations (82 for HRVT1, 164 for HRVT2) between LT-VTs and HRVTs. The standardized mean differences were trivial between HRVT1 and LT1-VT1 (SMD = 0.08, 95% CI -0.04-0.19, n = 22) and between HRVT2 and LT2-VT2 (SMD = -0.06, 95% CI -0.15-0.03, n = 42). The correlations were very strong between HRVT1 and LT1-VT1 (r = 0.85, 95% CI 0.75-0.91, n = 22), and between HRVT2 and LT2-VT2 (r = 0.85, 95% CI 0.80-0.89, n = 41). Moreover, subjects' characteristics, type of ergometer, or initial and incremental workload had no impact on HRVTs determination.

CONCLUSION

HRVTs showed trivial differences and very strong correlations with LT-VTs and might thus serve as surrogates. These results emphasize the usefulness of HRVTs as promising, accessible, and cost-effective means for exercise and clinical prescription purposes.

Menstrual Dysfunction in Adolescent Female Athletes

Despite the benefits of exercise on mental and physical health, excessive training loads can lead to health problems in the long term, including a wide spectrum of menstrual dysfunction (MD). This narrative review aims to analyze the relationship between physical exercise and MD in adolescent female athletes to support regular menstrual health monitoring and promote educational programs on reproductive risks. When dealing with MD in young athletes, several factors entangled with maturation of the hypothalamus-pituitary-ovarian axis should be considered. Firstly, some disciplines seem to have a higher prevalence of MD due to the high loads of training regimes and the early introduction of athletes to a competitive career. Moreover, low energy intake and a low body mass index appear to exacerbate existing MD. Lastly, disordered eating behaviors and psychological stress can contribute to MD in female athletes. The type of sport, influencing the intensity and duration of exercise, as well as individual psycho-physiological and environmental factors, may influence the role of physical activity in the manifestation of MD. Early recognition and management of MD, along with collaboration between sports organizations and health professionals, are crucial to minimize risks, ensure proper nutrition, and balance training with recovery. Keeping an open discussion on the topic may prospectively improve awareness, early diagnosis, and treatment strategies, as well as reduce injury risk and enhance sports performance.

Determinants of menstrual dysfunction in the female athlete triad: A cross-sectional study in Italian athletes

BACKGROUND

In 1992 the American College of Sports Medicine first described the Female Athlete Triad. The Triad is a metabolic injury involving three distinct clinical traits: low energy availability, with possible eating disorder, low bone mineral density and menstrual dysfunction (MD). Although the estimated prevalence of the Triad is low (1.2 %), single factors are common in female athletes, at all competitive levels and ages. Even though the Triad was described over two decades ago, the interrelation of the three diagnostics components is still debated: additional evidence is required to improve the multidisciplinary treatment approach for this complex condition. MD is one of the first signs of energy impairment. The present study aims at investigating MD determinants and predictors in female athletes, to allow an early diagnosis of the Triad and to implement adequate preventive strategies.

MATERIALS AND METHODS

An original structured questionnaire was composed to detect the presence of MD risk factors. Included participants were active female athletes within reproductive age range (15-40 years old). Anthropometric parameters and training-related factors, possibly affecting the regularity of the menstrual cycle, were investigated.

RESULTS

Respondents were 288 female athletes. Among them, 73.3 % were under 25 years of age; 6.6 % resulted underweight; 30.6 % reported to follow a meal plan/diet and 13.9 % declared to be a smoker. Lean sports were practiced by 30.6 % of responders. Body-weight congruence was detected in in 79.9 % of participants, whereas overestimation of body image was found in 16.3 % of athletes. Irregular menstrual cycle, a possible MD predictor, was present in 33.0 % of athletes, with 41.1 % practicing some lean sport (p = 0.007). Also, overestimation of body image suggested an increased risk of menstrual irregularity (p = 0.001). BMI <18.5 or BMI >30 could also act as risk factor, although significance was not fully obtained (p = 0.053). Overall, practice of lean sports and overestimation of body image appeared good determinants of increased menstrual irregularity (AOR 2.02 and 3.83, respectively).

CONCLUSIONS

Menstrual irregularity in female athletes can be considered an early predictor of MD: risk is further increased in athletes of lean sports and reporting an overestimation of self-perceived body image. Screenings and awareness programs should specifically address female athletes, because of their vulnerable-group profile. In order to define a standardized at-risk profile for Triad onset and sequelae likelihood, evaluation of menstrual regularity should especially be considered, in conjunction with the assessment of other indicators of energy availability (e.g. TEE, lean and fat mass, BMC). Testing for sport-derived stress and disordered eating attitudes is also recommended. Preventive strategy should involve the proactive engagement of sport clubs and periodic competitive sport medical assessment.

Physiology of Health and Performance: Enabling Success of Women in Combat Arms Roles

INTRODUCTION

The modern female soldier has yet to be fully characterized as she steps up to fill new combat roles that have only recently been opened to women. Both U.S. and U.K. military operational research efforts are supporting a science-based evolution of physical training and standards for female warfighters. The increasing representation of women in all military occupations makes it possible to discover and document the limits of female physiological performance.

METHOD

An informal Delphi process was used to synthesize an integrated concept of current military female physiological research priorities and emerging findings using a panel of subject matter experts who presented their research and perspectives during the second Women in Combat Summit hosted by the TriService Nursing Research Program in February 2021.

RESULTS

The physical characteristics of the modern soldier are changing as women train for nontraditional military roles, and they are emerging as stronger and leaner. Capabilities and physique will likely continue to evolve in response to new Army standards and training programs designed around science-based sex-neutral requirements. Strong bones may be a feature of the female pioneers who successfully complete training and secure roles traditionally reserved for men. Injury risk can be reduced by smarter, targeted training and with attention directed to female-specific hormonal status, biomechanics, and musculoskeletal architecture. An "estrogen advantage" appears to metabolically support enhanced mental endurance in physically demanding high-stress field conditions; a healthy estrogen environment is also essential for musculoskeletal health. The performance of female soldiers can be further enhanced by attention to equipment that serves their needs with seemingly simple solutions such as a suitable sports bra and personal protective equipment that accommodates the female anatomy.

CONCLUSIONS

Female physiological limits and performance have yet to be adequately defined as women move into new roles that were previously developed and reserved for men. Emerging evidence indicates much greater physical capacity and physiological resilience than previously postulated.

The Thyroid Hormone Axis and Female Reproduction

Thyroid function affects multiple sites of the female hypothalamic-pituitary gonadal (HPG) axis. Disruption of thyroid function has been linked to reproductive dysfunction in women and is associated with menstrual irregularity, infertility, poor pregnancy outcomes, and gynecological conditions such as premature ovarian insufficiency and polycystic ovarian syndrome. Thus, the complex molecular interplay between hormones involved in thyroid and reproductive functions is further compounded by the association of certain common autoimmune states with disorders of the thyroid and the HPG axes. Furthermore, in prepartum and intrapartum states, even relatively minor disruptions have been shown to adversely impact maternal and fetal outcomes, with some differences of opinion in the management of these conditions. In this review, we provide readers with a foundational understanding of the physiology and pathophysiology of thyroid hormone interactions with the female HPG axis. We also share clinical insights into the management of thyroid dysfunction in reproductive-aged women.

Menstrual Status and Pregnancy in Former Elite Long-Distance Runners With Menstrual Disorders

OBJECTIVE

To estimate the ratio of menstrual abnormalities, infertility, and other problems related to pregnancy and childbirth in former long-distance runners. We hypothesized that the female athlete triad during an athletic career affects future fertility and childbearing in former athletes.

DESIGN

Cross-sectional study.

SETTING

Participants of the All Japan University Women's Ekiden.

PARTICIPANTS

Female former athletes who competed at national level were asked to complete the questionnaire; 137 valid responses were obtained.

INDEPENDENT VARIABLES

Age at menarche and at the onset of pregnancy, history of amenorrhea and gynecological disorders, and lowest body mass index (BMI) during their athletic career.

MAIN OUTCOME MEASURES

Menstrual status, history of pregnancy and childbirth, any related infertility treatment and problems, and history of stress fractures.

RESULTS

The mean age at menarche was 13.3 ± 2.2 (range, 10-25) years. Five athletes (3.6%) had primary amenorrhea. Eleven of the 137 participants (8.0%) required treatment for infertility. Sixty participants had 121 pregnancies, of which 5 were yet to deliver during the survey. Fifteen of 116 pregnancies (12.9%) ended in miscarriage, induced abortion, or stillbirth. Logistic regression analysis showed that the factors related to "infertility treatment" were age at the onset of pregnancy ( P = 0.047) and higher BMI during their athletic career ( P = 0.032; odds ratio, 2.19).

CONCLUSIONS

The main factor influencing infertility was an older age at the time of pregnancy, similar to that observed in the general population. Amenorrhea or being underweight during their athletic career was not associated with problems related to conception and childbirth.

Identifying latent classes of Relative Energy Deficiency in Sport (RED-S) consequences in a sample of collegiate female cross country runners

OBJECTIVE

The purpose of this study was to identify patterns of clustering of the 10 health consequences identified in the Relative Energy Deficiency in Sport (RED-S) framework among collegiate female Cross-Country runners. We also assessed risk characteristics associated with each cluster.

METHODS

This randomly sampled population included 211 current National Collegiate Athletics Association (NCAA) Division I (DI) female cross country runners who completed a quantitative survey. We used latent class analysis (LCA) to group athletes into mutually exclusive classes based on shared response patterns of RED-S consequences. We computed descriptive statistics to identify demographics, personal characteristics, disordered eating and emotional health characteristics associated with each class.

RESULTS

The average age of the sample was 21 years with mean body mass index 20.4 kg/m². The LCA identified three unique classes of potential RED-S presentations: (1) low probability of RED-S consequences; (2) complex physical and psychological concerns with a higher burden of cardiovascular concern and (3) very high probability of anxiety with high burden of menstrual disturbance, bone injury and gastrointestinal concern. All classes were characterised by high levels of menstrual disturbance and distinguished by the number and burden of other potential RED-S consequences and in reported abuse history, emotional regulation and perfectionism.

CONCLUSION

This study identified a high burden of menstrual disturbance in NCAA D1 cross country runners, and three unique presentations of RED-S consequences. Future research is warranted to better understand how early prevention and intervention strategies may mitigate RED-S consequences in distance runners.

Repeated Superovulation Accelerates Primordial Follicle Activation and Atresia

For humans, ARTs (assisted reproductive technologies) have become the most effective method to treat subfertility/infertility in clinic. To obtain enough oocytes during ART, ovarian stimulation is performed by exogenous hormones, and some patients undergo several ovarian stimulation cycles. Although some adverse effects of ARTs on women and offspring are reported, few studies are focused on the effects of multiple superovulation on ovarian reserve. In the present study, we found that repeated superovulation significantly reduced primordial follicle number and the serum AMH. Compared to the decreased antral follicle number, the expression of genes related to primordial follicle activation, such as Foxo3, Akt, and Rptor, and the atretic follicle number in ovaries were increased by superovulation times. We further found that repeated superovulation reduced the plasma level of FSH, LH, and estradiol, and increased the expression of genes related to apoptosis (Bax, Casp3 (caspase-3), Casp8, and Casp9) in granulosa cells, providing evidence that repeated superovulation disrupted the balance between survival and death in granulosa cells. In summary, our results suggest that repeated superovulation has adverse effects on folliculogenesis.

Cognition, Behavior, Sexuality, and Autonomic Responses of Women with Hypothalamic Amenorrhea

(1) Background: Functional Hypothalamic Amenorrhea (FHA) can be caused by the hyper activation of neuro-endocrine responses to stress. Among other endocrine factors and hypothalamic dysfunctions, the psychophysiological stress response can very frequently lead to an inhibition of the gonadal-pituitary axis. The aim of this study was to investigate the level of neurovegetative activation in a group of young women affected by this condition. (2) Methods: Twenty-five women (mean age = 21.1 ± 4.34) with FHA were consecutively recruited. Information on psycho-physiological distress was collected through a Psychopathological assessment (with the administration of three psychometric tests) and the Psychophysiological Stress Profile (PSP). Their data were compared with a control group. (3) Results: In the PSP, the patients displayed significantly higher values compared to controls in terms of the parameters of muscle tension (sEMG), skin conductance (SCL/SCR), heart rate (HR), and peripheral temperature (PT). Furthermore, autonomic hyper-activation at rest, marked reactivity to stress, and reduced recovery were seen. Moreover, a condition characterized by psychological distress (anxiety and somatic complaints, depressed and irritable mood, obsessive-compulsive traits) emerged. (4) Conclusions: The results highlight autonomic hyper-activation in FHA, which is also associated with psychological distress. Considering that FHA is a condition that affects multiple systems between mind and body, a multimodal, multidimensional, and multidisciplinary assessment of stress is becoming an emerging need.

Moderate Weight Loss is associated with Reductions in LH Pulse Frequency and Increases in 24-hour Cortisol with no change in Perceived Stress in Young Ovulatory Women

OBJECTIVE

Determine the potential role of cortisol as an indicator of both metabolic and psychosocial stress and its relation to LH pulse dynamics during a three-month diet and exercise intervention causing moderate weight loss.

METHODS

Secondary analysis of a randomized, controlled trial that demonstrated the causal role of low energy availability in the disruption of the menstrual cycle. Twenty-one women aged (18-24 yrs), BMI (21.7± 1.9 kg·m^-2), completed a baseline menstrual cycle and three intervention menstrual cycles of a controlled diet and supervised exercise program. Twenty-four-hour LH pulse dynamics (q10 min) and diurnal patterns of cortisol (q60 min) as well as Perceived Stress Scale scores were determined in the early follicular phase prior to the intervention and in the post intervention cycle. Pre to post comparisons were determined with paired t-tests, and Pearson bivariate correlations assessed associations.

RESULTS

Subjects lost weight (-2.8±1.97 kg) and LH pulse frequency declined pre=0.79±0.23 pulses·hr^-1 to post=0.60±0.29 pulses·hr^-1 (p=0.014). Weight loss was associated with an increase in cortisol AUC R=-0.473, (p=0.03) and the decline in LH pulse frequency R= 0.523; (p=0.026). Increases in cortisol AUC were associated with declines in LH pulse frequency R=-0.472; (p=0.048). The morning cortisol rise AUC increased from pre=2140±878 µg·dL^-1 · day to post=2556±1067 µg·dL^-1 · day (p=0.034). Changes in PSS were not associated with changes in LH or cortisol.

CONCLUSION

The initial perturbation of LH pulsatility with moderate diet and exercise is associated with metabolically driven increases in cortisol AUC with no influence of psychological stress.

Etiology and management of amenorrhea in adolescent and young adult women

In this article, we will review the etiology and management of amenorrhea in adolescent and young adult women, beginning with the diagnostic work-up and followed by etiologies organized by system. Most cases of amenorrhea are caused by dysfunction of the hypothalamic-pituitary-ovarian (HPO) axis, which is the major regulator of the female reproductive hormones: estrogen and progesterone.  We begin by reviewing hypothalamic etiologies, including eating disorders and relative energy deficiency in sport. Then, pituitary causes of amenorrhea are reviewed, including hyperprolactinemia, empty sella syndrome, Sheehan's syndrome and Cushing's syndrome. Next, ovarian causes of amenorrhea are reviewed, including polycystic ovarian syndrome and primary ovarian insufficiency. Finally, other etiologies of amenorrhea are discussed, including thyroid disease, adrenal disease and reproductive tract anomalies. In conclusion, there is a wide and diverse range of causes of amenorrhea in adolescents that originate from any level of the HPO axis, as well as anatomic and chromosomal etiologies.   Treatment should be focused on the underlying cause. Preservation of bone density and risk of fractures should be discussed with amenorrheic patients since many causes of amenorrhea can result in decreased bone density and may be irreversible.

Regulation of stress response on the hypothalamic-pituitary-gonadal axis via gonadotropin-inhibitory hormone

Under stressful condition, reproductive function is impaired due to the activation of various components of the hypothalamic-pituitaryadrenal (HPA) axis, which can suppress the activity of the hypothalamic-pituitary-gonadal (HPG) axis at multiple levels. A hypothalamic neuropeptide, gonadotropin-inhibitory hormone (GnIH) is a key negative regulator of reproduction that governs the HPG axis. Converging lines of evidence have suggested that different stress types and their duration, such as physical or psychological, and acute or chronic, can modulate the GnIH system. To clarify the sensitivity and reactivity of the GnIH system in response to stress, we summarize and critically review the available studies that investigated the effects of various stressors, such as restraint, nutritional/metabolic and social stress, on GnIH expression and/or its neuronal activity leading to altered HPG action. In this review, we focus on GnIH as the potential novel mediator responsible for stress-induced reproductive dysfunction.

Effect of exercise intensity and duration on the levels of stress hormones and hypothalamic-pituitary-gonadal axis in adult male rats: an experimental study

PURPOSE

The effect of exercise on stress has been demonstrated in several studies which have shown that exercise intensity and duration have various effects on the reproductive axis. This study evaluated the effect of different intensities and durations of exercise on the hormonal indices of stress, such as corticosterone (CORT), norepinephrine (NEP), and also reproductive performance indices, including gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), and testosterone (T).

METHODS

In this experimental study, 30 adult Wistar rats were randomly divided into five groups as follows: no-exercise, RME-1 (regular moderate exercise for 1 month), RME-6 (regular moderate exercise for 6 months), RIE-1 (regular intensive exercise for 1 month), and RIE-6 (regular intensive exercise for 6 months). At the end of the experiment, the serum levels of the abovementioned hormones and hypothalamic expression of the Gnrh gene were measured using the enzyme-linked immunosorbent assay and the real-time polymerase chain reaction method, respectively.

RESULTS

The levels of stress hormones, including CORT and NEP, increased only in the RIE-1 group compared with the no-exercise group. In addition, an increase was observed in T hormone levels in the RME-1 group compared with those in the no-exercise group, whereas LH and T hormone levels showed a greater decrease in the RIE-6 group than in the no-exercise group. Gnrh expression levels showed an increase and a decrease in the RME-1 and RIE-6 groups compared with the no-exercise group, respectively.

CONCLUSION

These results confirmed the effects of different intensities and durations of exercise on sex hormone levels.

Has Menstruation Disappeared? Functional Hypothalamic Amenorrhea-What Is This Story about?

Functional hypothalamic amenorrhea (FHA) is a very common condition affecting women of procreative age. There are many reasons for this disorder, including a low availability of energy in the diet, low micro- and macronutrient intake, overly intensive physical activity, disturbed regeneration processes, sleep disorders, stress, and psychological disorders. The main determinant is long-term stress and an inability to handle the effects of that stress. FHA is a very complex disorder and often goes undiagnosed. Moreover, therapeutic interventions do not address all the causes of the disorder, which could have implications for women’s health. As shown by scientific reports, this condition can be reversed by modifying its causes. This review of the literature aims to update the current knowledge of functional hypothalamic amenorrhea and underscores the complexity of the disorder, with particular emphasis on the nutritional aspects and potential interventions for restoring balance.

A review of the pathophysiology of functional hypothalamic amenorrhoea in women subject to psychological stress, disordered eating, excessive exercise or a combination of these factors

INTRODUCTION

Functional hypothalamic amenorrhoea (FHA) is a common form of secondary amenorrhoea without an identifiable structural cause. Suppression of gonadotrophin-releasing hormone (GnRH) pulsatility results in reduced luteinizing hormone (LH) levels, with subsequent reduction in oestradiol, anovulation and cessation of menstruation. GnRH pulsatility suppression is a recognized complication of psychological stress, disordered eating, low body weight, excessive exercise or a combination of these factors.

PATHOPHYSIOLOGY OF FHA

Individuals with FHA demonstrate low energy availability (EA), body fat percentage and energy expenditure. Documented adipocytokine changes notably, raised adiponectin, ghrelin, PYY, and decreased leptin, are associated with GnRH suppression. Other endocrine responses seen in this low EA state include low insulin levels, low total T3, increased basal cortisol levels and a reduced response to corticotrophin-releasing hormone (CRH) administration. FHA is associated with raised growth hormone (GH) and low insulin-like growth factor (IGF-1), suggesting relative GH resistance. Kisspeptins are a group of polypeptides, recently discovered to play a major role in the regulation of the reproductive axis through influencing GnRH release. KNDy (kisspeptin/neurokinin B/dynorphin) act on GnRH neurons and a multitude of factors result in their release.

IMPLICATIONS FOR FUTURE TREATMENT

Management of FHA is imperative to prevent adverse outcomes in bone density, cardiovascular risk profile, psychological well-being and fertility. Outwith modification of nutritional intake and exercise, limited therapeutic strategies are currently available for women with FHA. Advancements in the understanding of the pathophysiological basis of this under-recognized and under-treated clinical entity will aid management and may result in the development of novel therapeutic approaches.

Reproductive and metabolic adaptation to multistressor training in women

Hypothalamic-pituitary-gonadal (HPG) axis suppression in exercising women can be caused by low energy availability (EA), but the impact of a real-world, multistressor training environment on reproductive and metabolic function is unknown. This study aimed to characterize reproductive and metabolic adaptation in women undertaking basic military training. A prospective cohort study in women undertaking 11-month initial military training (n = 47) was carried out. Dynamic low-dose 1-h gonadotrophin-releasing hormone (GnRH) tests were completed after 0 and 7 mo of training. Urine progesterone was sampled weekly throughout. Body composition (dual X-ray absorptiometry), fasting insulin resistance (homeostatic modeling assessment 2, HOMA2), leptin, sex steroids, anti-Müllerian hormone (AMH), and inhibin B were measured after 0, 7, and 11 mo with an additional assessment of body composition at 3 mo. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) responses were suppressed after 7 mo (both P < 0.001). Among noncontraceptive users (n = 20), 65% had regular (23-35 days) cycles preenrollment, falling to 24% by 7 mo of training. Of women in whom urine progesterone was measured (n = 24), 87% of cycles showed no evidence of ovulation. There was little change in AMH, LH, and estradiol, although inhibin B and FSH increased (P < 0.05). Fat mass fluctuated during training but at month 11 was unchanged from baseline. Fat-free mass did not change. Visceral adiposity, HOMA2, and leptin increased (all P < 0.001). HPG axis suppression with anovulation occurred in response to training without evidence of low EA. Increased insulin resistance may have contributed to the observed pituitary and ovarian dysfunction. Our findings are likely to represent an adaptive response of reproductive function to the multistressor nature of military training.NEW & NOTEWORTHY We characterized reproductive endocrine adaptation to prolonged arduous multistressor training in women. We identified marked suppression of hypothalamic-pituitary-gonadal (HPG) axis function during training but found no evidence of low energy availability despite high energy requirements. Our findings suggest a complex interplay of psychological and environmental stressors with suppression of the HPG axis via activation of the hypothalamic-pituitary adrenal (HPA) axis. The neuroendocrine impact of nonexercise stressors on the HPG axis during arduous training should be considered.

Overtraining Syndrome (OTS) and Relative Energy Deficiency in Sport (RED-S): Shared Pathways, Symptoms and Complexities

The symptom similarities between training-overload (with or without an Overtraining Syndrome (OTS) diagnosis) and Relative Energy Deficiency in Sport (RED-S) are significant, with both initiating from a hypothalamic-pituitary origin, that can be influenced by low carbohydrate (CHO) and energy availability (EA). In this narrative review we wish to showcase that many of the negative outcomes of training-overload (with, or without an OTS diagnosis) may be primarily due to misdiagnosed under-fueling, or RED-S, via low EA and/or low CHO availability. Accordingly, we undertook an analysis of training-overload/OTS type studies that have also collected and analyzed for energy intake (EI), CHO, exercise energy expenditure (EEE) and/or EA. Eighteen of the 21 studies (86%) that met our criteria showed indications of an EA decrease or difference between two cohorts within a given study (n = 14 studies) or CHO availability decrease (n = 4 studies) during the training-overload/OTS period, resulting in both training-overload/OTS and RED-S symptom outcomes compared to control conditions. Furthermore, we demonstrate significantly similar symptom overlaps across much of the OTS (n = 57 studies) and RED-S/Female Athlete Triad (n = 88 studies) literature. It is important to note that the prevention of under-recovery is multi-factorial, but many aspects are based around EA and CHO availability. Herein we have demonstrated that OTS and RED-S have many shared pathways, symptoms, and diagnostic complexities. Substantial attention is required to increase the knowledge and awareness of RED-S, and to enhance the diagnostic accuracy of both OTS and RED-S, to allow clinicians to more accurately exclude LEA/RED-S from OTS diagnoses.

The Female Athlete Triad/Relative Energy Deficiency in Sports (RED-S)

In a healthy athlete, the caloric intake is sufficient for sports energy needs and body physiological functions, allowing a balance between energy availability, bone metabolism, and menstrual cycle. On the other hand, an imbalance caused by low energy availability due to a restrictive diet, eating disorders or long periods of energy expenditure leads to multisystemic deregulation favoring the essential functions of the body. This phenomenon, described as the female athlete triad, occurs in a considerable percentage of high-performance athletes, with harmful consequences for their future. The present review was carried out based on a critical analysis of the most recent publications available and aims to provide a global perception of the topic relative energy deficit in sport (RED-S). The objective is to promote the acquisition of more consolidated knowledge on an undervalued theme, enabling the acquisition of preventive strategies, early diagnosis and/or appropriate treatment.

A Review of Nonpharmacological Strategies in the Treatment of Relative Energy Deficiency in Sport

Relative energy deficiency in sport (RED-S) can result in negative health and performance outcomes in both male and female athletes. The underlying etiology of RED-S is low energy availability (LEA), which occurs when there is insufficient dietary energy intake to meet exercise energy expenditure, corrected for fat-free mass, leaving inadequate energy available to ensure homeostasis and adequate energy turnover (optimize normal bodily functions to positively impact health), but also optimizing recovery, training adaptations, and performance. As such, treatment of RED-S involves increasing energy intake and/or decreasing exercise energy expenditure to address the underlying LEA. Clinically, however, the time burden and methodological errors associated with the quantification of energy intake, exercise energy expenditure, and fat-free mass to assess energy availability in free-living conditions make it difficult for the practitioner to implement in everyday practice. Furthermore, interpretation is complicated by the lack of validated energy availability thresholds, which can result in compromised health and performance outcomes in male and female athletes across various stages of maturation, ethnic races, and different types of sports. This narrative review focuses on pragmatic nonpharmacological strategies in the treatment of RED-S, featuring factors such as low carbohydrate availability, within-day prolonged periods of LEA, insufficient intake of bone-building nutrients, lack of mechanical bone stress, and/or psychogenic stress. This includes the implementation of strategies that address exacerbating factors of LEA, as well as novel treatment methods and underlying mechanisms of action, while highlighting areas of further research.

Recovery of menses after functional hypothalamic amenorrhoea: if, when and why

BACKGROUND

Prolonged amenorrhoea occurs as a consequence of functional hypothalamic amenorrhoea (FHA) which is most often induced by weight loss, vigorous exercise or emotional stress. Unfortunately, removal of these triggers does not always result in the return of menses. The prevalence and conditions underlying the timing of return of menses vary strongly and some women report amenorrhoea several years after having achieved and maintained normal weight and/or energy balance. A better understanding of these factors would also allow improved counselling in the context of infertility. Although BMI, percentage body fat and hormonal parameters are known to be involved in the initiation of the menstrual cycle, their role in the physiology of return of menses is currently poorly understood. We summarise here the current knowledge on the epidemiology and physiology of return of menses.

OBJECTIVE AND RATIONALE

The aim of this review was to provide an overview of (i) factors determining the recovery of menses and its timing, (ii) how such factors may exert their physiological effects and (iii) whether there are useful therapeutic options to induce recovery.

SEARCH METHODS

We searched articles published in English, French or German language containing keywords related to return of menses after FHA published in PubMed between 1966 and February 2020. Manuscripts reporting data on either the epidemiology or the physiology of recovery of menses were included and bibliographies were reviewed for further relevant literature. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria served to assess quality of observational studies.

OUTCOMES

Few studies investigate return of menses and most of them have serious qualitative and methodological limitations. These include (i) the lack of precise definitions for FHA or resumption of menses, (ii) the use of short observation periods with unsatisfactory descriptions and (iii) the inclusion of poorly characterised small study groups. The comparison of studies is further hampered by very inhomogeneous study designs. Consequently, the exact prevalence of resumption of menses after FHA is unknown. Also, the timepoint of return of menses varies strongly and reliable prediction models are lacking. While weight, body fat and energy availability are associated with the return of menses, psychological factors also have a strong impact on the menstrual cycle and on behaviour known to increase the risk of FHA. Drug therapies with metreleptin or naltrexone might represent further opportunities to increase the chances of return of menses, but these require further evaluation.

WIDER IMPLICATIONS

Although knowledge on the physiology of return of menses is presently rudimentary, the available data indicate the importance of BMI/weight (gain), energy balance and mental health. The physiological processes and genetics underlying the impact of these factors on the return of menses require further research. Larger prospective studies are necessary to identify clinical parameters for accurate prediction of return of menses as well as reliable therapeutic options.

A Clinician's Guide to Functional Hypothalamic Amenorrhea

Patients and clinicians alike want to know if stress causes infertility. Stress could impair with reproductive function by a variety of mechanisms, including compromise of ovarian function, spermatogenesis, fertilization, endometrial development, implantation, and placentation. Herein we focus on the pathogenesis and treatment of stress-induced anovulation, which is often termed functional hypothalamic amenorrhea (FHA), with the objective of summarizing the actual knowledge as a clinical guide. FHA is a reversible form of anovulation due to slowing of gonadotropin-releasing hormone pulse frequency that results in insufficient pituitary secretion of gonadotropins to support full folliculogenesis. Importantly, FHA heralds a constellation of neuroendocrine alterations with health concomitants. The activity of the hypothalamic-pituitary-adrenal axis is increased in women with FHA and this observation supports the notion that stress is the cause. The extent of reproductive suppression relates to individual endocrinological and physiological sensitivity to stressors, both metabolic and psychogenic, and chronicity.

Eating behaviours related to psychological stress are associated with functional hypothalamic amenorrhoea in exercising women

Functional hypothalamic amenorrhoea (FHA) can occur due to the independent or combined effects of psychogenic and energetic stressors. In exercising women, research has primarily focused on energy deficiency as the cause of FHA while psychological stressors have been ignored. To assess both psychological and metabolic factors associated with FHA in exercising women, we performed across-sectional comparison of 61 exercising women (≥2 hours/week, age 18-35 years, BMI 16-25kg/m²), who were eumenorrheic or amenorrhoeic confirmed by daily urine samples assayed for reproductive hormone metabolites. Psychological factors and eating behaviours were assessed by self-report questionnaires. Exercising women with FHA had lower resting metabolic rate (p=0.023), T3 (p<0.001), T4 (p=0.013), leptin (p=0.002), higher peptide YY (p<0.001), greater drive for thinness (p=0.017), greater dietary cognitive restraint (p<0.001), and displayed dysfunctional attitudes, i.e., need for social approval (p=0.047) compared to eumenorrheic women. Amenorrhoeic women displayed asignificant positive correlation between the need for social approval and drive for thinness with indicators of stress, depression, and mood, which was not apparent in eumenorrheic women. In exercising women with FHA, eating behaviours are positively related to indicators of psychological stress and depression.

Effect of Inflammation on Female Gonadotropin-Releasing Hormone (GnRH) Neurons: Mechanisms and Consequences

: Inflammation has a well-known suppressive effect on fertility. The function of gonadotropin-releasing hormone (GnRH) neurons, the central regulator of fertility is substantially altered during inflammation in females. In our review we discuss the latest results on how the function of GnRH neurons is modified by inflammation in females. We first address the various effects of inflammation on GnRH neurons and their functional consequences. Second, we survey the possible mechanisms underlying the inflammation-induced actions on GnRH neurons. The role of several factors will be discerned in transmitting inflammatory signals to the GnRH neurons: cytokines, kisspeptin, RFamide-related peptides, estradiol and the anti-inflammatory cholinergic pathway. Since aging and obesity are both characterized by reproductive decline our review also focuses on the mechanisms and pathophysiological consequences of the impact of inflammation on GnRH neurons in aging and obesity.

Can improvement in hormonal and energy balance reverse cardiovascular risk factors in athletes with amenorrhea?

Female athletes display a high prevalence of hypothalamic amenorrhea as a result of energy imbalance. In these athletes with amenorrhea, decreased luteinizing hormone/follicule-stimulating hormone secretion leads to deficiency in endogenous estrogen. The severe estrogen deficiency in these athletes may increase cardiovascular risk similar to that in postmenopausal women. This review discusses the potential cardiovascular risk factors in athletes with amenorrhea as a result of hypoestrogenism, which include endothelial dysfunction and unfavorable lipid profiles. We also consider the potential to reverse the cardiovascular risk by restoring energy or hormonal imbalance along the reproductive axis in athletes with amenorrhea.

Bone health in elite Norwegian endurance cyclists and runners: a cross-sectional study

Background

Athletes who compete in non-weight-bearing activities such as swimming and cycling are at risk of developing low bone mineral density (BMD). Athletes in long-distance running are at risk of low BMD.

Objective

(1) To evaluate the bone health in Norwegian male and female national elite road cyclists and middle-distance and long-distance runners, and to identify cases of low BMD. (2) To identify possible risk factors associated with low BMD.

Methods

Twenty-one runners (11 females and 10 males) and 19 road cyclists (7 females and 12 males) were enrolled in this cross-sectional study. Dual-energy X-ray absorptiometry measurement of BMD in total body, femoral neck and lumbar spine was measured. Participants completed a questionnaire regarding training, injuries, calcium intake and health variables.

Results

The cyclists had lower BMD for all measured sites compared with the runners (p≤0.05). Ten of 19 cyclists were classified as having low BMD according to American College of Sports Medicine criteria (Z-score ≤−1), despite reporting to train heavy resistance training on the lower extremities. Low BMD was site specific having occurred in the lumbar spine and the femoral neck and was not confined to females. Type of sport was the only factor significantly associated with low BMD.

Conclusion

National elite Norwegian road cyclists had lower BMD compared with runners, and a large proportion was classified as having low BMD, despite having performed heavy resistance training. Interventions to increase BMD in this population should be considered.

The Unexplored Crossroads of the Female Athlete Triad and Iron Deficiency: A Narrative Review

Despite the severity and prevalence of iron deficiency in exercising women, few published reports have explored how iron deficiency interacts with another prevalent and severe condition in exercising women: the 'female athlete triad.' This review aims to describe how iron deficiency may interact with each component of the female athlete triad, that is, energy status, reproductive function, and bone health. The effects of iron deficiency on energy status are discussed in regards to thyroid function, metabolic fuel availability, eating behaviors, and energy expenditure. The interactions between iron deficiency and reproductive function are explored by discussing the potentially impaired fertility and hyperprolactinemia due to iron deficiency and the alterations in iron metabolism due to menstrual blood loss and estrogen exposure. The interaction of iron deficiency with bone health may occur via dysregulation of the growth hormone/insulin-like growth factor-1 axis, hypoxia, and hypothyroidism. Based on these discussions, several future directions for research are presented.

Pitfalls of Conducting and Interpreting Estimates of Energy Availability in Free-Living Athletes

The human body requires energy for numerous functions including, growth, thermogenesis, reproduction, cellular maintenance, and movement. In sports nutrition, energy availability (EA) is defined as the energy available to support these basic physiological functions and good health once the energy cost of exercise is deducted from energy intake (EI), relative to an athlete’s fat-free mass (FFM). Low EA provides a unifying theory to link numerous disorders seen in both female and male athletes, described by the syndrome Relative Energy Deficiency in Sport, and related to restricted energy intake, excessive exercise or a combination of both. These outcomes are incurred in different dose–response patterns relative to the reduction in EA below a “healthy” level of ∼45 kcal·kg FFM−1·day−1. Although EA estimates are being used to guide and monitor athletic practices, as well as support a diagnosis of Relative Energy Deficiency in Sport, problems associated with the measurement and interpretation of EA in the field should be explored. These include the lack of a universal protocol for the calculation of EA, the resources needed to achieve estimates of each of the components of the equation, and the residual errors in these estimates. The lack of a clear definition of the value for EA that is considered “low” reflects problems around its measurement, as well as differences between individuals and individual components of “normal”/“healthy” function. Finally, further investigation of nutrition and exercise behavior including within- and between-day energy spread and dietary characteristics is warranted since it may directly contribute to low EA or its secondary problems.

The roles of kisspeptin and gonadotropin inhibitory hormone in stress-induced reproductive disorders

Several kinds of stress suppress the hypothalamic-pituitary-gonadal (HPG) axis and reproductive behavior in humans and animals. These changes can eventually cause diseases and disorders, such as amenorrhea and infertility. In previous studies, it has been shown that stress-related factors, e.g., corticotropin-releasing hormone, cortisol, and pro-inflammatory cytokines, promote the stress-induced suppression of the HPG axis. However, these mechanisms are not sufficient to explain how stress suppresses HPG axis activity, and it has been suggested that some other factors might also be involved. In the early 21st century, novel neuroendocrine peptides, kisspeptin and gonadotropin inhibitory hormone (GnIH)/RFamide-related peptide 3 (RFRP-3), which directly regulate GnRH/gonadotropin synthesis and secretion, were newly discovered. Growing evidence indicates that kisspeptin and GnIH/RFRP-3 play pivotal roles in the stress-induced disruption of the HPG axis and reproductive behavior in addition to their physiological functions. This review summarizes what is currently known about the roles of kisspeptin and GnIH/RFRP-3 in stress-induced reproductive disorders.

Female Athlete Triad: Future Directions for Energy Availability and Eating Disorder Research and Practice

Despite more than 3 decades of research on the Female Athlete Triad, research gaps remain. Although low energy availability (EA) is the key etiologic factor in the Triad and the pathways to low EA are varied, its effects can be modified by several factors. Accurate screening, diagnosis, and treatment of disordered eating are a challenge; however, recent techniques combined with novel educational and behavior interventions prove promising. Recently published practice-based guidelines have helped to translate Triad science and should improve as they are refined. This article identifies the current state of research and distinguishes areas that require further investigation.

Hypothalamic Amenorrhea and the Long-Term Health Consequences

The menstrual cycle is a reproductive vital sign and provides insight into hormonal imbalance as well as pregnancy. The significance of estrogen, however, extends beyond fertility and plays a role on tissues and organs throughout the body. Functional hypothalamic amenorrhea is a common form of secondary amenorrhea resulting in estrogen deficiency in young premenopausal women. While reversible, the cause of this disorder is related to psychological stress, excessive exercise, disordered eating or a combination of these factors resulting in suppression of the hypothalamic–pituitary–ovarian axis. The resulting loss of estrogen has profound effects on many systems throughout the body including cardiac, skeletal, psychological and reproductive. Often, these young women are the ‘walking well’ as they do not have bothersome symptoms of low estrogen and are unaware of the consequences of estrogen deficiency. This review focuses on the health consequences of hypothalamic amenorrhea, current research and available treatment options.

Functional Hypothalamic Amenorrhea: An Endocrine Society Clinical Practice Guideline

COSPONSORING ASSOCIATIONS

The American Society for Reproductive Medicine, the European Society of Endocrinology, and the Pediatric Endocrine Society. This guideline was funded by the Endocrine Society.

OBJECTIVE

To formulate clinical practice guidelines for the diagnosis and treatment of functional hypothalamic amenorrhea (FHA).

PARTICIPANTS

The participants include an Endocrine Society-appointed task force of eight experts, a methodologist, and a medical writer.

EVIDENCE

This evidence-based guideline was developed using the Grading of Recommendations, Assessment, Development, and Evaluation approach to describe the strength of recommendations and the quality of evidence. The task force commissioned two systematic reviews and used the best available evidence from other published systematic reviews and individual studies.

CONSENSUS PROCESS

One group meeting, several conference calls, and e-mail communications enabled consensus. Endocrine Society committees and members and cosponsoring organizations reviewed and commented on preliminary drafts of this guideline.

CONCLUSIONS

FHA is a form of chronic anovulation, not due to identifiable organic causes, but often associated with stress, weight loss, excessive exercise, or a combination thereof. Investigations should include assessment of systemic and endocrinologic etiologies, as FHA is a diagnosis of exclusion. A multidisciplinary treatment approach is necessary, including medical, dietary, and mental health support. Medical complications include, among others, bone loss and infertility, and appropriate therapies are under debate and investigation.

Gonadotropin-Inhibitory Hormone Plays Roles in Stress-Induced Reproductive Dysfunction

Physical and psychological stressors suppress hypothalamic-pituitary-gonadal axis activity and sexual behavior and consequently induce reproductive dysfunction. Recently, it has been shown that gonadotropin-inhibitory hormone (GnIH), also called RFamide-related peptide 3 (RFRP) in mammals, which is a potent inhibitory regulator of gonadotropin-releasing hormone (GnRH) and gonadotropin, is involved in stress-induced reproductive dysfunction. GnIH/Rfrp (the gene coding RFRP-3) expression and activity are increased by psychological and immune stress, and this alteration suppresses GnRH and gonadotropin secretion. Glucocorticoid acts as a mediator that interacts between stress and hypothalamic GnIH/RFRP-3. GnIH/RFRP-3 also plays important roles in stress-induced suppression of sexual behavior and infertility, and genetic silencing of GnIH/Rfrp completely recovers sexual behavior and fertility. This review summarizes what is currently known about the roles of GnIH in stress-induced reproductive dysfunction.

Magnitude of daily energy deficit predicts frequency but not severity of menstrual disturbances associated with exercise and caloric restriction

We assessed the impact of energy deficiency on menstrual function using controlled feeding and supervised exercise over four menstrual cycles (1 baseline and 3 intervention cycles) in untrained, eumenorrheic women aged 18-30 yr. Subjects were randomized to either an exercising control (EXCON) or one of three exercising energy deficit (ED) groups, i.e., mild (ED1; -8 ± 2%), moderate (ED2; -22 ± 3%), or severe (ED3; -42 ± 3%). Menstrual cycle length and changes in urinary concentrations of estrone-1-glucuronide, pregnanediol glucuronide, and midcycle luteinizing hormone were assessed. Thirty-four subjects completed the study. Weight loss occurred in ED1 (-3.8 ± 0.2 kg), ED2 (-2.8 ± 0.6 kg), and ED3 (-2.6 ± 1.1 kg) but was minimal in EXCON (-0.9 ± 0.7 kg). The overall sum of disturbances (luteal phase defects, anovulation, and oligomenorrhea) was greater in ED2 compared with EXCON and greater in ED3 compared with EXCON AND ED1. The average percent energy deficit was the main predictor of the frequency of menstrual disturbances (f = 10.1, β = -0.48, r(2) = 0.23, P = 0.003) even when weight loss was included in the model. The estimates of the magnitude of energy deficiency associated with menstrual disturbances ranged from -22 (ED2) to -42% (ED3), reflecting an energy deficit of -470 to -810 kcal/day, respectively. This is the first study to demonstrate a dose-response relationship between the magnitude of energy deficiency and the frequency of exercise-related menstrual disturbances; however, the severity of menstrual disturbances was not dependent on the magnitude of energy deficiency.

Athletic activity and hormone concentrations in high school female athletes

CONTEXT

Physical activity may affect the concentrations of circulating endogenous hormones in female athletes. Understanding the relationship between athletic and physical activity and circulating female hormone concentrations is critical.

OBJECTIVE

To test the hypotheses that (1) the estradiol-progesterone profile of high school adolescent girls participating in training, conditioning, and competition would differ from that of physically inactive, age-matched adolescent girls throughout a 3-month period; and (2) athletic training and conditioning would alter body composition (muscle, bone), leading to an increasingly greater lean-body-mass to fat-body-mass ratio with accompanying hormonal changes.

DESIGN

Cohort study.

SETTINGS

Laboratory and participants' homes.

PATIENTS OR OTHER PARTICIPANTS

A total of 106 adolescent girls, ages 14-18 years, who had experienced at least 3 menstrual cycles in their lifetime.

MAIN OUTCOME MEASURE(S)

Participants were prospectively monitored throughout a 13-week period, with weekly physical activity assessments and 15 urine samples for estrogen, luteinizing hormone, creatinine, and progesterone concentrations. Each girl underwent body-composition measurements before and after the study period.

RESULTS

Seventy-four of the 98 girls (76%) who completed the study classified themselves as athletes. Body mass index, body mass, and fat measures remained stable, and 17 teenagers had no complete menstrual cycle during the observation period. Mean concentrations of log(estrogen/creatinine) were slightly greater in nonathletes who had cycles of <24 or >35 days. Mean log(progesterone/creatinine) concentrations in nonathletes were less in the first half and greater in the second half of the cycle, but the differences were not statistically significant.

CONCLUSIONS

A moderate level of athletic or physical activity did not influence urine concentrations of estrogen, progesterone, or luteinizing hormones. However, none of the participants achieved high levels of physical activity. A significant number (17%) of girls in both activity groups were amenorrheic during the 3-month study period.

Hypothalamic Kiss1 and RFRP gene expressions are changed by a high dose of lipopolysaccharide in female rats

Reproductive function is suppressed by several types of stress. Hypothalamic kisspeptin, which is a product of the Kiss1 gene, and GnIH/RFRP have pivotal roles in the regulation of GnRH and gonadotropins through their receptors Kiss1r and GPR147 in many species. However, alterations of these factors under stress conditions have not been fully evaluated. This study investigated the mechanisms of immune stress-induced reproductive dysfunction, especially focusing on the changes of Kiss1 and RFRP gene expression. Serum LH levels and hypothalamic Kiss1 and GnRH mRNA levels were decreased, while hypothalamic RFRP and GPR147 mRNA levels were increased by administration of a high dose of LPS (5mg/kg) in both ovariectomized and gonadal intact female rats. In this condition, Kiss1 and/or RFRP mRNA levels were positively and negatively correlated with GnRH expression, respectively. In contrast, hypothalamic Kiss1, RFRP, and GPR147 mRNA levels were not changed by administration of a moderate dose of LPS (500μg/kg) in ovariectomized rats. Rats with high-dose LPS injection showed more prolonged fever responses and severe anorexia compared with rats with moderate-dose LPS injection, indicating that more energy was used for the immune response in the former. These results suggest that the underlying mechanisms of dysfunction of gonadotropin secretion are changed according to the severity of immune stress, and that changes of some reserved factors, such as kisspeptin and RFRP, begin to participate in the suppression of GnRH and gonadotropin in severe conditions. As reproduction needs a large amount of energy, dysfunction of gonadotropin secretion under immune stress may be a biophylatic mechanism by which more energy is saved for the immune response.

Female athlete triad and its components: toward improved screening and management

As female athletic participation has increased, the positive effects of exercise on health have become evident. However, with this growth in sports activity, a set of health problems unique to the female athlete has emerged. The female athlete triad as first described in 1992 by the American College of Sports Medicine consisted of disordered eating, amenorrhea, and osteoporosis; the definition was updated in 2007 to include a spectrum of dysfunction related to energy availability, menstrual function, and bone mineral density. For this review, a comprehensive search of databases-MEDLINE In-Process & Other Non-Indexed Citations, MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and Scopus, from earliest inclusive dates to January 2013-was conducted by an experienced librarian with input from the authors. Controlled vocabulary supplemented with keywords such as female athlete triad, amenorrhea, oligomenorrhea, fracture, osteopenia, osteoporosis, bone disease, anorexia, bulimia, disordered eating, low energy availability was used to search for articles on female athlete triad. Articles addressing the prevalence, screening, and management of the female athlete triad were selected for inclusion in the review. This article reviews the current definitions of the triad components, epidemiology, pathophysiology, and recommended screening and management guidelines. The lack of efficacy of current screening of athletes is highlighted. Low energy availablity, from either dietary restriction or increased expenditure, plays a pivotal role in development of the triad. Athletes involved in "lean sports" (those that emphasize weight categories or aesthetics, such as ballet, gymnastics, or endurance running) are at highest risk. Treatment is centered on restoring energy availability to reverse adverse changes in the metabolic milieu. Prevention and early recognition of triad disorders are crucial to ensure timely intervention. Caregivers and physicians of female athletes must remain vigilant in education, recognition, and treatment of athletes at risk.