Prevalence of individual and combined components of the female athlete triad

Female athletes: a state-of-the-art review of multiorgan influence of exercise training

Endurance sports have witnessed an increase in female participation, demanding a constant and evolving reassessment of the specific physiological and health implications of female athletes. In the present review, we analyze cardiovascular, hematological adaptations and anthropometry and hormonal fluctuations highlighting sex-specific differences in response to exercise, with estrogen playing a fundamental role in modulating body composition and metabolic processes. Nutritional aspects, in particular energy availability, macronutrient distribution and hydration, are fundamental in supporting training demands and menstrual function. Nevertheless, the repercussions of nutritional deficiencies, interacting in the female athlete triad - which also includes amenorrhea, osteoporosis and eating disorders - underline the importance of comprehensive management strategies. In addition, we comprehensively discuss the multiorgan effects of physical training, highlighting the intersections between sex-specific differences, nutritional needs, and cardiovascular adaptations. Cardiovascular remodeling in female endurance athletes reveals both morphological and functional adaptations, requiring a deep understanding of effective cardiovascular risk assessment and screening. The synthesis of current knowledge highlights the complexity of the physiological landscape of the female athlete practicing endurance sports, requiring ongoing exploration and tailored interventions. In conclusion, this review aims to support a gender-based approach to athletic training and health management and research, intending to optimize performance while safeguarding the well-being of female athletes.

[Difficulties of differential diagnosis of functional hypothalamic amenorrhea and polycystic ovary syndrome: a systematic review]

BACKGROUND

Functional hypothalamic amenorrhea (FHA) and polycystic ovary syndrome (PCOS) are pathologies most common in women of reproductive age. Menstrual irregularities (oligo/amenorrhea) are the most common symptom of these diseases. FHA develops against the background of stress or excessive physical exertion, and is characterized by inhibition of neuroendocrine regulation of the hypothalamic-pituitary-ovarian axis with a subsequent decrease in the production of sex steroids. For PCOS, the most important pathogenetic links are insulin resistance and hyperandrogenism. The pathology of neuroendocrine regulation in ovarian hyperandrogenism is accompanied by excessive pulsatile secretion of gonadotropin-releasing hormone (GnRH), promoting increased production of luteinizing hormone (LH). Both FHA and PCOS lead to multiple complications from other organs and systems: cardiovascular pathology, decreased bone mineral density with prolonged amenorrhea and contribute to the development of infertility.

OBJECTIVE

To analyze the works studying the problems of differential diagnosis of FHA and PCOS.

METHODS

Using PubMed, eLibrary, CyberLeninka.ru, a systematic search was conducted for articles published over the past 6 years that met the following criteria: the research that describe methods and develop criteria for the differential diagnosis of FHA and PCOS. Selected impactive publications within 1998-2018 were also included in the review.

RESULTS

This review highlights the differential diagnostic criteria for FHA and PCOS. The features of clinical, laboratory and instrumental studies are also described. Publications describing the coexistence of these pathologies in women are analyzed, and methods that allow differentiating these nosologies are described in detail.

CONCLUSION

A correct and timely diagnosis facilitates the prescription of appropriate treatment regimens, reduces the incidence of complications and improves the quality of life of women. In light of recent advances in the description of the mechanisms of neuroendocrine regulation of the reproductive system, it is necessary to further conduct research to study the role of neuropeptides in the development of FHA and PCOS, which may serve to create more accurate diagnostic markers of diseases.

Energy availability and its association with health-related outcomes among national athletes at risk of relative energy deficiency in sports (REDs)

ABSTRACT

Background

Low energy availability (LEA) occurs when athletes' energy intake fails to match the energy expended during exercise, resulting in insufficient energy to support essential functions for optimal health, a condition known as relative energy deficiency in sports (REDs).

Objective

This study aims to explore the prevalence of LEA among Malaysian national athletes and its associations with health-related outcomes.

Methods

A total of 43 athletes (51.2% males, aged 18-40) identified previously as having moderate or high risk of REDs through a questionnaire underwent comprehensive clinical assessments. Resting metabolic rate (RMR) was measured using indirect calorimetry, with an RMR ratio of <0.90 indicating LEA. Weight and height were measured, and fasting blood samples were analysed for ferritin, free triiodothyronine (fT3), follicle-stimulating hormone (FSH), luteinising hormone (LH), estradiol (female athletes) and testosterone (male athletes). Bone mineral density (BMD) of the lumbar spine and total left hip, as well as body composition, were measured using dual-energy X-ray absorptiometry (DXA).

Results

Out of the 43 athletes, 12 showed evidence of LEA, exhibiting at least one of the following characteristics: low estradiol levels (87.5%), low testosterone (75.0%), low fT3 (66.7%), low LH (58.3%), low FSH (58.3%), low ferritin (25.0%) and low BMD (8.3%). Notably, fT3, estradiol and testosterone were significant predictors for LEA.

Conclusions

A low but noteworthy incidence of LEA among Malaysian national athletes was associated with hormone imbalances. Awareness about LEA among athletes and sports personnel is essential for early detection and appropriate intervention.

Multi-organ transcriptome atlas of a mouse model of relative energy deficiency in sport

Insufficient energy intake to meet energy expenditure demands of physical activity can result in systemic neuroendocrine and metabolic abnormalities in activity-dependent anorexia and relative energy deficiency in sport (REDs). REDs affects >40% of athletes, yet the lack of underlying molecular changes has been a hurdle to have a better understanding of REDs and its treatment. To assess the molecular changes in response to energy deficiency, we implemented the "exercise-for-food" paradigm, in which food reward size is determined by wheel-running activity. By using this paradigm, we replicated several aspects of REDs in female and male mice with high physical activity and gradually reduced food intake, which results in weight loss, compromised bone health, organ-specific mass changes, and altered rest-activity patterns. By integrating transcriptomics of 19 different organs, we provide a comprehensive dataset that will guide future understanding of REDs and may provide important implications for metabolic health and (athletic) performance.

High prevalence of stress fractures and long-term amenorrhoea in high endurance female athletes: The misleading lack of correlation with bone mineral density

Aim & objectives

Females who engage in high levels of sports have a high prevalence of menstrual cycle disorders and bone stress injuries (BSI). In this study, we determined the prevalence of menstrual disorders and fractures in female athletes and their association with bone mineral density (BMD) parameters.

Material & methods

Cross-Sectional Study. Forty-one female athletes from a public High-Performance Regional Centre; 24 high-endurance athletes (HEA) and 17 other athletes, were included. To form the control group, we invited medical students from a public University. Twenty-nine non-athletes (NA) were included. A health surveys and a dual-energy X-ray absorptiometry (DXA) were conducted for all participants.

Results

Among the participants (median age, 24 years; body mass index, 21 kg/m2), the percentage of long-term amenorrhoea was 42 % in HEA vs. 0 % in NHEA (OR 25.35; 95 % CI 1.37-470.50, p = 0.008) or 10 % in NA (OR 6.20; 95 % CI 1.46-26.24, p = 0.022), and the percentage of BSI was 29 % in HEA vs. 0 % in NHEA or NA. Both groups of female athletes (HEA and NHEA) showed higher Z-scores than those of NA in the femur; however, only NHEA had a significant increase in the BMD on lumbar spine than that of NA.

Conclusion

The prevalence of long-term amenorrhoea and/or BSI was significantly higher in the HEA than in the NHEA or NA females. In contrast, HEA, like NHEA, had higher BMD values in the femur than those of controls. It is unlikely that DXA parameters can be used to estimate cortical BSI risk in this population.

The risk of low energy availability among athlete females in Saudi Arabia: a cross-sectional study

Introduction

Low energy availability (LEA) is a state of inadequate energy reserves that results from a negative energy balance. This condition can lead to severe health risks such as amenorrhea and osteoporosis. Various causes for LEA, such as eating disorders and exercise addiction, have been reported in the literature. However, data in Saudi Arabia are lacking. This cross-sectional study measures the prevalence of LEA, eating disorders, and exercise addiction among adult females in Saudi Arabia and identifies possible associated risk factors.

Methods

The sample comprised 119 female athletes who filled out an online survey adapted from the LEA in Females Questionnaire, the Eating Disorder Examination Questionnaire, and the Exercise Addiction Inventory.

Results

Participants showed a high prevalence of LEA (66.4%), eating disorder (33.6%), and exercise addiction (10.1%), confirming the association between normal weight and LEA in females living in Saudi Arabia (p < 0.00).

Discussion and conclusion

With an increasing number of females in the country interested in following a healthy lifestyle, there is a need to raise the awareness of the population on the issues of LEA, eating disorders, and exercise addiction and their effects on the body by developing educational programs about energy intake and healthy physical activity routines.

Sex hormone mediated change on flexion reflex

It has been shown that estrogen and progesterone receptors are expressed in the spinal cord; therefore, fluctuation in their concentrations may affect the spinal network and modulate the control of movement. Herein, we assessed the neuro-modulatory effect of sex hormones on the polysynaptic spinal network by using a flexion reflex network as a model system. Twenty-four healthy eumenorrheic women (age 21-37 years) were tested every other day for one menstrual cycle. Serum estradiol and progesterone were acquired at the time of testing. The flexion reflex of the tibialis anterior was elicited by sending an innocuous electrical stimulus directly to the posterior tibial nerve or plantar cutaneous afferent. Analyses were performed for each menstrual cycle phase: the follicular phase and the luteal phase. Increases in estradiol or progesterone concentrations were not associated with reflex duration or root mean squared (RMS) amplitude in either the follicular or luteal phases. In the luteal phase, an increase in the estradiol concentration was associated with a longer latency of the reflex (b = 0.23, p = 0.038). The estradiol × progesterone interaction was found towards significance (b = -0.017, p = 0.081). These results highlight the potential synergistic effect of estradiol and progesterone and may provide indirect confirmatory evidence of the observed modulatory effect.

An assessment of the diagnosis, treatment, and outcomes of lower extremity stress fractures in pediatric and adolescent populations

OBJECTIVES

To present one of the first descriptive case series of pediatric and adolescent lower extremity stress injuries, their management, and outcomes in athletes and non-athletes.

METHODS

The IRB-approved retrospective study included patients under 18 years at a tertiary children's hospital who were diagnosed with a lower extremity stress fracture/reaction. Demographic data, mechanism of injury, physical exam, radiographic findings, treatment, & outcomes were collected. Descriptive statistical analysis was conducted.

RESULTS

Ninety-seven patients with stress injuries on clinical exams and on radiographs or MRI were included. The average age when diagnosed was 11.7 years (range 1.1-18 years) and the most common injuries were to the tibia (n = 33, 28.4%) and the least common involved were the cuneiforms (n = 4, 3.4%). Patients under the age of 14 were more likely to experience cuboid and calcaneal stress injuries (mean age 5.5 and 8.3 years respectively). Nineteen patients (19.6%) had high-risk stress fractures, with the average age of 14.9 years versus 11.6 for those with low risk (p-value = 0.01) and return to activity time being 15 weeks compared to 10.5 (p-value = 0.027). The most common forms of treatment were controlled ankle motion (CAM), walker boots (58.6%), and physical therapy (PT) (38.1%). The mean Lower Extremity Function Score of the patient population was 73.8, indicating no clinically important difference from full functionality.

CONCLUSION

Lower extremity stress injuries in this cohort were most seen in the tibia, although patients younger than 14 had a high number of cuboid and calcaneal stress injuries. Those with high-risk stress fractures were older and took longer to recover from when compared to low-risk injuries. Treatment is commonly conservative, with CAM boots and PT being the most frequently utilized interventions and serving as a successful approach to treatment, with patients returning to activity at an average of 11.4 weeks, which is comparable to similar studies.

The general nutrition practices of competitive powerlifters vary by competitive calibre and sex, weight, and age class

PURPOSE

To characterise self-reported nutrition practices and beliefs of powerlifters.

METHODS

Actively competing male (n = 240) and female (n = 65) powerlifters completed a cross-sectional online survey of self-reported nutrition practices across the competitive cycle, within specific competitive phases, and hard and easy training days. Data are presented as number (n) and percentage (%) of all powerlifters practicing a given strategy followed by a % of responses reporting various practices or beliefs within this strategy. Differences in categorical sub-groups (sex, age, and weight class; and competitive calibre) were analysed with a chi-square test and denoted where significant (p ≤ 0.05).

RESULTS

Most powerlifters reported following a specific diet long-term (n = 203, 66.6%) of which If It Fits Your Macros (IIFYM)/flexible dieting was most common (n = 159, 78.3%). Over half reported introducing a special diet for a competitive phase (n = 162, 53.1%), of which IIFYM/flexible dieting was most followed for competition preparation (n = 80, 63%) and off-season (n = 48, 71.6%). Compared to normal dietary intake, most reported eating more on harder training days (n = 219, 71.8%) and refraining from eating less on easier training days (n = 186, 61%).

CONCLUSIONS

IIFYM/flexible dieting is commonly followed by powerlifters to support performance and body composition goals. Females seemed to report more often restricting energy and dieting for body composition reasons than males. Powerlifters tailor their energy intake on harder training days to the higher training demands but refrain from reducing energy intake on rest/easier training days.

Energy constraint and compensation: Insights from endurance athletes

The Constrained Model of Total Energy Expenditure predicts that increased physical activity may not influence total energy expenditure, but instead, induces compensatory energetic savings in other processes. Much remains unknown, however, about concepts of energy expenditure, constraint and compensation in different populations, and it is unclear whether this model applies to endurance athletes, who expend very large amounts of energy during training and competition. Furthermore, it is well-established that some endurance athletes consciously or unconsciously fail to meet their energy requirements via adequate food intake, thus exacerbating the extent of energetic stress that they experience. Within this review we A) Describe unique characteristics of endurance athletes that render them a useful model to investigate energy constraints and compensations, B) Consider the factors that may combine to constrain activity and total energy expenditure, and C) Describe compensations that occur when activity energy expenditure is high and unmet by adequate energy intake. Our main conclusions are as follows: A) Higher activity levels, as observed in endurance athletes, may indeed increase total energy expenditure, albeit to a lesser degree than may be predicted by an additive model, given that some compensation is likely to occur; B) That while a range of factors may combine to constrain sustained high activity levels, the ability to ingest, digest, absorb and deliver sufficient calories from food to the working muscle is likely the primary determinant in most situations and C) That energetic compensation that occurs in the face of high activity expenditure may be primarily driven by low energy availability i.e., the amount of energy available for all biological processes after the demands of exercise have been met, and not by activity expenditure per se.

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.

Amenorrhea and oligomenorrhea risk related to exercise training volume and intensity: Findings from 3705 participants recruited via the STRAVA™ exercise application

OBJECTIVES

To investigate associations between self-reported exercise training habits and amenorrhea/oligomenorrhea among physically active women.

DESIGN

A cross-sectional survey was completed by 3705 women (median age = 40 years [quartile 1, quartile 3: 30, 45], body mass index = 22.1 kg/m2 [20.5, 24.2]) representing multiple nationalities and sports via the STRAVA™ exercise application. Respondents selected the amount of time they participated in low intensity, moderate intensity, and high intensity exercise training per week. Amenorrhea/oligomenorrhea was defined as self-reporting ≤10 menses in the last year.

METHODS

Associations between weekly exercise volume for low intensity training, moderate intensity training, and high intensity training and amenorrhea/oligomenorrhea were modeled with univariate logistic regression models, followed by adjustment for age and body mass index.

RESULTS

Amenorrhea/oligomenorrhea prevalence was 16 % (n = 576/3705), with no difference by country of origin or most sport modes. In adjusted models, participating in low intensity training ≥7 h/week or moderate intensity training ≥6 h/week was associated with 1.43 (95 % confidence interval: 1.04-1.96) and 1.46 (1.10-1.95) greater odds of amenorrhea/oligomenorrhea compared to 2 to 3 h/week, respectively. Similarly, high intensity training ≥5 h/week was associated with 1.41 (1.03-1.92) greater odds of amenorrhea/oligomenorrhea compared to 1 to 2 h/week. Participating in low intensity training for ≤30 min/week compared to 2 to 3 h/week was associated with reduced amenorrhea/oligomenorrhea odds (0.65 [0.44-0.94]).

CONCLUSIONS

Taken together, these associations suggest greater weekly exercise volume, irrespective of intensity, may increase amenorrhea/oligomenorrhea risk among physically active women.

Contraception, female cycle disorders and injuries in Swiss female elite athletes-a cross sectional study

Aim: The national Olympic committee of Switzerland has conducted an online survey among female elite athletes with a focus on cycle disorders, contraception, and injuries in 2021. Methods: A total of 1,092 female elite athletes from 107 different sports were asked to answer the questionnaire. A descriptive analysis was carried out to determine location parameters and create frequency tables. Results: The questionnaire was completed by 408 athletes (37.4%) from 92 different sports. 43.4% participated in a lean sport. 57.1% reported no injuries, 32.6% one injury, and 10.2% two or more injuries per year. A considerable proportion reported being affected by primary amenorrhoea (10.8%). Primary amenorrhoea occurred significantly more often in female athletes with a BMI lower than 21.7 kg/m2 (15.2%) than in athletes with a BMI above 21.7 kg/m2 (7.4%, p = 0.021). Considering contraception, 25.8% of female athletes were currently using an oral contraceptive pill. The proportion of female athletes not using contraception at all or using non-hormonal contraceptive methods was high at 54.4%. In lean sports, significantly more athletes used no or non-hormonal contraceptives (p < 0.05). Conclusion: Among top Swiss female athletes, a considerable proportion used non-hormonal or no contraceptives. This trend was more evident in lean sports. Delayed menarche and cycle irregularities were common among female athletes, especially among athletes with high training volumes as well as a BMI below 21.7 kg/m2. This orienting survey underlines the importance of specialized gynecological care for elite female athletes.

Multidisciplinary physician survey assessing knowledge of the female athlete triad and relative energy deficiency in sport

BACKGROUND

Short and long-term health consequences surrounding Low Energy Availability can be mitigated by recognizing the risk factors and making early diagnosis of the Female Athlete Triad (Triad) and Relative Energy Deficiency in Sport (RED-S). While awareness of the Triad among physicians and allied health professionals has been studied, there are very few studies that assess physician awareness of both the Triad and RED-S.

METHODS

Our study assesses Low Energy Availability, the Triad, and RED-S knowledge with an electronic survey, educational handout, and follow up survey among physicians across multiple specialties at a single academic institution.

RESULTS

Among 161 respondents, respective Triad and RED-S awareness among surveyed specialties was highest in Orthopedic surgeons (100%, 100%), followed by Physical Medicine & Rehabilitation (70%, 53%), Family Medicine (67%, 48%), Internal Medicine (54%, 36%), Obstetrics and Gynecology (46%, 32%), Pediatrics (45%, 29%), Endocrinology (33%, 33%), and Other (33%, 33%). Comparing the initial survey results to the follow-up survey results, there was an increase from 37 to 72% of physicians who correctly identified that the presence of low BMI or recent weight loss is not a required component of the Triad or RED-S. Both the initial and follow-up survey revealed a continued misperception surrounding the use of hormonal contraception to resume menstrual cycles, with 33% of physicians on initial survey and 44% of physicians on follow-up survey incorrectly answering that question.

CONCLUSIONS

Multidisciplinary physicians have various levels of knowledge surrounding the Triad and RED-S, and there is a need for improved physician awareness, diagnosis, and treatment of the Triad and RED-S. Misperceptions exist surrounding the role of hormonal contraception in female athletes with the Triad and RED-S to regain and regulate menses.

Examination of the Cumulative Risk Assessment and Nutritional Profiles among College Ballet Dancers

This study examined female collegiate ballet dancers' (n = 28) Female Athlete Triad (Triad) risk via the Cumulative Risk Assessment (CRA) and nutritional profiles (macro- and micronutrients; n = 26). The CRA identified Triad return to play criteria (RTP: Full Clearance, Provisional Clearance, or Restricted/Medical Disqualified) by assessing eating disorder risk, low energy availability, menstrual cycle dysfunction, and low bone mineral density. Seven-day dietary assessments identified any energy imbalances of macro- and micronutrients. Ballet dancers were identified as low, within normal, or high for each of the 19 nutrients assessed. Basic descriptive statistics assessed CRA risk classification and dietary macro- and micronutrient levels. Dancers averaged 3.5 ± 1.6 total score on the CRA. Based on these scores, the RTP outcomes revealed Full Clearance 7.1%, n = 2; Provisional Clearance 82.1%, n = 23; and Restricted/Medical Disqualification 10.7%, n = 3. Dietary reports revealed that 96.2% (n = 25) of ballet dancers were low in carbohydrates, 92.3% (n = 24) low in protein, 19.2% (n = 5) low in fat percent, 19.2% (n = 5) exceeding saturated fats, 100% (n = 26) low in Vitamin D, and 96.2% (n = 25) low in calcium. Due to the variability in individual risks and nutrient requirements, a patient-centered approach is a critical part of early prevention, evaluation, intervention, and healthcare for the Triad and nutritional-based clinical evaluations.

Female Athlete Triad and Male Athlete Triad Syndrome Induced by Low Energy Availability: An Animal Model

Energy availability (EA) is defined the difference in energy intake and exercise energy expenditure. Reduction of EA (i.e. Low energy availability, LEA) often causes abnormalities of reproduction system and drastic bone loss in some female athletes, the phenomenon is called as female athlete triad. More than ever before, it is considered a serious problem, the reason of these are (1) the syndrome occurred in female athletes but also male athletes, (2) LEA is leads to dysfunction of various organs other than reproductive system (Relative energy deficiency in sport, RED-S). On the other hand, we have focused on this syndrome and have proposed novel insights into the physiological effects of LEA on bone and solutions through nutritional treatment by recreating it in animal models. In this review, we will summarize the epidemiological and physiological perspectives of these diseases from historical background to recent findings, and introduce the usefulness of using animal models to explore mechanisms and treatments.

The development and validation of a questionnaire to assess relative energy deficiency in sport (RED-S) knowledge

OBJECTIVES

The aim of this study was to develop and validate a questionnaire assessing knowledge of signs and symptoms of relative energy deficiency in sport among healthcareprofessionals and physically active individuals.

DESIGN

Cross-sectional study.

METHODS

The questionnaire was created in two phases: 1)Item development was established through a literature review, expert review (n = 4), and pre-testing among healthcare professionals, dietetic students, and the general population (n = 35). 2) Validity (item analysis, construct validity) and internal reliability were assessed by administrating the questionnaire to healthcare professionals (n = 97) and physically active individuals who engaged in moderate to intense physical activity (n=77). The questionnaire was re-administered in a subset of the same groups (n = 88) for test-retest reliability.

RESULTS

The expert responses showed >80% acceptability and pretesting through interviews indicated good content and face validity. Item response analysis resulted in removal of 6 items due to low discrimination ability. Significantly higher knowledge scores in health professionals compared with non-health professionals (mean difference (95% CI) = 2.8 (1.9, 3.7)) confirmed construct validity. Internal consistency, assessed using Cronbach's alpha (α = 0.79), and test-retest reliability using intra-class correlation coefficients (intra-class correlation coefficients = 0.80; Spearman's correlation = 0.84, p < 0.001) were good. The final questionnaire had 18 items assessing knowledge of signs and symptoms of Relative Energy Deficiency in Sport.

CONCLUSIONS

The questionnaire provides a valid and reliable tool to assess knowledge of signs and symptoms of Relative Energy Deficiency in Sport among health professionals and physically active individuals, which could guide future education requirements by assessing current knowledge.

Bone Perspectives in Functional Hypothalamic Amenorrhoea: An Update and Future Avenues

One of the most important and potentially long-lasting detrimental consequences of Functional Hypothalamic Amenorrhoea (FHA) is on skeletal homeostasis. Beyond oestrogen deficiency, FHA is associated with a cascade of additional neuro-endocrine and metabolic alterations, some adaptive, but which combine to disrupt skeletal homeostasis. Ultimately, this leads to a two-fold increased risk of fractures in women with FHA compared to healthy eumenorrhoeic women. Although the cornerstone of management of FHA-related bone loss remains recovery of menses via restoration of metabolic/psychological balance, there is rapidly developing evidence for hormonal manipulations (with a particular emphasis on route of administration) and other pharmacological treatments that can protect or improve skeletal homeostasis in FHA. In this mini-review, we provide an update on the pathophysiology, clinical management and future avenues in the field from a bone perspective.

Risk of Low Energy Availability, Disordered Eating, Exercise Addiction, and Food Intolerances in Female Endurance Athletes

Relative energy deficiency in sport (RED-S) is a complex syndrome describing health and performance consequences of low energy availability (LEA) and is common among female endurance athletes. Various underlying causes of LEA have been reported, including disordered eating behavior (DE), but studies investigating the association with exercise addiction and food intolerances are lacking. Therefore, the aim of this cross-sectional study was to investigate the association between DE, exercise addiction and food intolerances in athletes at risk of LEA compared to those with low risk. Female endurance athletes, 18-35 years, training ≥5 times/week were recruited in Norway, Sweden, Ireland, and Germany. Participants completed an online-survey comprising the LEA in Females Questionnaire (LEAF-Q), Exercise Addiction Inventory (EAI), Eating Disorder Examination Questionnaire (EDE-Q), and questions regarding food intolerances. Of the 202 participants who met the inclusion criteria and completed the online survey, 65% were at risk of LEA, 23% were at risk of exercise addiction, and 21% had DE. Athletes at risk of LEA had higher EDE-Q and EAI scores compared to athletes with low risk. EAI score remained higher in athletes with risk of LEA after excluding athletes with DE. Athletes at risk of LEA did not report more food intolerances (17 vs. 10%, P = 0.198), but were more frequently reported by athletes with DE (28 vs. 11%, P = 0.004). In conclusion, these athletes had a high risk of LEA, exercise addiction, and DE. Exercise addiction should be considered as an additional risk factor in the prevention, early detection, and targeted treatment of RED-S among female endurance athletes.

Impact of Low Energy Availability on Skeletal Health in Physically Active Adults

For decades researchers reported that pre-menopausal women who engage in extensive endurance exercise and have menstrual dysfunction can develop low bone mineral density (BMD) or osteoporosis. More recently, low energy availability has been recognized as the initiating factor for low BMD in these women. Furthermore, the relationship between low energy availability and poor skeletal health is not exclusive to women engaging in endurance exercise. Rather, both males and females commonly experience endocrine dysfunction resulting from low energy availability and high exercise levels that degrades skeletal health. Consequences to skeletal health can range from short-term changes in bone metabolism and increased risk of bone stress injuries to long-term consequences of low BMD, such as osteoporosis and related fragility fractures. The degree to which low energy availability degrades skeletal health may be dependent on the length and extent of the energy deficit. However, the complex relationships between under-fueling, short- and long-term skeletal consequences and the factors that mediate these relationships are not well described. In this review, we discuss the consequences of low energy availability on sex hormones and skeletal health in two highly-active populations-athletes and military trainees-and provide a summary of existing knowledge gaps for future study.

Contributing Factors to Low Energy Availability in Female Athletes: A Narrative Review of Energy Availability, Training Demands, Nutrition Barriers, Body Image, and Disordered Eating

Relative Energy Deficiency in sport is experiencing remarkable popularity of late, particularly among female athletes. This condition is underpinned by low energy availability, which is a byproduct of high energy expenditure, inadequate energy intake, or a combination of the two. Several contributing factors exist that may predispose an athlete to low energy availability, and therefore a holistic and comprehensive assessment may be required to identify the root causes. The focus of the current narrative review is to discuss the primary contributing factors as well as known risk factors for low energy availability among female athletes to help practitioners increase awareness on the topic and identify future areas of focus.

A Life History Perspective on Athletes with Low Energy Availability

The energy costs of athletic training can be substantial, and deficits arising from costs unmet by adequate energy intake, leading to a state of low energy availability, may adversely impact athlete health and performance. Life history theory is a branch of evolutionary theory that recognizes that the way the body uses energy-and responds to low energy availability-is an evolved trait. Energy is a finite resource that must be distributed throughout the body to simultaneously fuel all biological processes. When energy availability is low, insufficient energy may be available to equally support all processes. As energy used for one function cannot be used for others, energetic "trade-offs" will arise. Biological processes offering the greatest immediate survival value will be protected, even if this results in energy being diverted away from others, potentially leading to their downregulation. Athletes with low energy availability provide a useful model for anthropologists investigating the biological trade-offs that occur when energy is scarce, while the broader conceptual framework provided by life history theory may be useful to sport and exercise researchers who investigate the influence of low energy availability on athlete health and performance. The goals of this review are: (1) to describe the core tenets of life history theory; (2) consider trade-offs that might occur in athletes with low energy availability in the context of four broad biological areas: reproduction, somatic maintenance, growth, and immunity; and (3) use this evolutionary perspective to consider potential directions for future research.

Prevalence of Risk Factors of the Female Athlete Triad among Young Elite Athletes of Pakistan

BACKGROUND

Female athletes who are not vigilant about their food choices and choose extraneous physical activities may head towards negative health effects.

PURPOSE

The purpose was to determine the prevalence of risk factors that may lead to the Female Athlete Triad among young elite athletes in Pakistan.

STUDY DESIGN & METHODS

A cross sectional questionnaire-based study was conducted in 2018 at Pakistan Sports Board to investigate the risk factors of The Female Athlete Triad among young elite athletes based in national training camps of major metropolitan cities. Trained and professional female elite athletes of age 18 - 25 years, able to comprehend questionnaire in English were included. Athletes completed the questionnaire including demographics, educational qualifications, Body Mass Index, sports participation, and playing hours. The Eating Aptitude Test-26 (EAT-26) and questionnaires on risks of amenorrhea and risks of low bone mineral density were completed. Individual prevalence of the risk factors of three components was assessed. The data were analyzed using SPSS-20 and descriptive statistics applied.

RESULTS

A sample of 60 elite athletes, (23.57 + 2.37 years, BMI 21.97 +1.90) who participated in various sports were included. EAT-26 results indicated that 50% of athletes were at risk of an eating disorder. Disordered Eating behaviors in need of referral were identified in 83.3%. Risks for amenorrhea were identified in 15%, and concerning low Bone Mineral Density, no risks were identified, except the intake of caffeinated beverages in 51.7%.

CONCLUSION

The prevalence of risk for disordered eating was found to be significant among female elite athletes of Pakistan, but risk of amenorrhea and low bone mineral density were not of major concern.

LEVEL OF EVIDENCE

3b.

Examination of the Prevalence of Female Athlete Triad Components among Competitive Cheerleaders

The purpose of this study was to examine individual and combined Female Athlete Triad components within collegiate cheerleaders, an at-risk group. Cheerleaders (n = 19; age: 20.3 ± 1.2 years) completed anthropometric measurements, health history questionnaires, resting metabolic rate, the eating disorder inventory-3 and symptom checklist, blood sample, and DXA scan. Participants completed dietary and exercise logs for 7 days and used heart rate monitors to track daily and exercise energy expenditure. Proportions were calculated for low energy availability (LEA) risk, disordered eating risk, and pathogenic behaviors. Chi-square analysis was used to determine the difference between cheerleaders who experience low EA with or without disordered eating risk. All cheerleaders demonstrated LEA for the days they participated in cheerleading practice, 52.6% demonstrated LEA with eating disorder risk and 47.4% demonstrated LEA without eating disorder risk, 52.6% self-reported menstrual dysfunction, 14% experienced menstrual dysfunction via hormonal assessment, and 0% demonstrated low bone mineral density. Overall, 47.7% presented with one Triad component, 52.6% demonstrated two Triad components using self-reported menstrual data, and 10.5% demonstrated two Triad components using hormonal assessments. All cheerleaders displayed LEA. These findings support the need for increased education on the individual components of the Triad and their potential consequences by qualified personal.

Bone health in functional hypothalamic amenorrhea: What the endocrinologist needs to know

In the original definition by Klinefelter, Albright and Griswold, the expression "hypothalamic hypoestrogenism" was used to describe functional hypothalamic amenorrhoea (FHA). Given the well-known effects of estrogens on bone, the physiopathology of skeletal fragility in this condition may appear self-explanatory. Actually, a growing body of evidence has clarified that estrogens are only part of the story. FHA occurs in eating disorders, overtraining, and during psychological or physical stress. Despite some specific characteristics which differentiate these conditions, relative energy deficiency is a common trigger that initiates the metabolic and endocrine derangements contributing to bone loss. Conversely, data on the impact of amenorrhoea on bone density or microarchitecture are controversial, and reduced bone mass is observed even in patients with preserved menstrual cycle. Consistently, oral estrogen-progestin combinations have not proven beneficial on bone density of amenorrheic women. Low bone density is a highly prevalent finding in these patients and entails an increased risk of stress or fragility fractures, and failure to achieve peak bone mass and target height in young girls. Pharmacological treatments have been studied, including androgens, insulin-like growth factor-1, bisphosphonates, denosumab, teriparatide, leptin, but none of them is currently approved for use in FHA. A timely screening for bone complications and a multidisciplinary, customized approach aiming to restore energy balance, ensure adequate protein, calcium and vitamin D intake, and reverse the detrimental metabolic-endocrine changes typical of this condition, should be the preferred approach until further studies are available.

The Relationship Between Bone and Reproductive Hormones Beyond Estrogens and Androgens

Reproductive hormones play a crucial role in the growth and maintenance of the mammalian skeleton. Indeed, the biological significance for this hormonal regulation of skeletal homeostasis is best illustrated by common clinical reproductive disorders, such as primary ovarian insufficiency, hypothalamic amenorrhea, congenital hypogonadotropic hypogonadism, and early menopause, which contribute to the clinical burden of low bone mineral density and increased risk for fragility fracture. Emerging evidence relating to traditional reproductive hormones and the recent discovery of newer reproductive neuropeptides and hormones has deepened our understanding of the interaction between bone and the reproductive system. In this review, we provide a contemporary summary of the literature examining the relationship between bone biology and reproductive signals that extend beyond estrogens and androgens, and include kisspeptin, gonadotropin-releasing hormone, follicle-stimulating hormone, luteinizing hormone, prolactin, progesterone, inhibin, activin, and relaxin. A comprehensive and up-to-date review of the recent basic and clinical research advances is essential given the prevalence of clinical reproductive disorders, the emerging roles of upstream reproductive hormones in bone physiology, as well as the urgent need to develop novel safe and effective therapies for bone fragility in a rapidly aging population.

The LEAF questionnaire is a good screening tool for the identification of the Female Athlete Triad/Relative Energy Deficiency in Sport among young football players

Background

It has been noticed that Female Athlete Triad (Fat) and Relative Energy Deficiency (Red-S) in Sport are characterized by the symptoms of impaired endocrine-metabolic function and bone health in female athletes. In addition, it may be evaluated with a qualitative tool, such as Low Energy Availability in Females questionnaire (LEAF-Q) and quantitative measurements: bone mineral density (BMD), resting energy expenditure (REE), body composition, 24-hour dietary recall.

Methods

The aim of this study was to assess the prevalence of Triad and Red-S using the LEAF-Q in youth female football players. Additionally, the difference in the BMD, body composition, REE and energy intake (EI) were assessed between the Triad/Red-S risk and not at-risk groups.

Results

Almost two thirds (64.7%) of participants are classified as being at-risk for the triad according to their LEAF-Q scores. There were no statistically significant differences (p > 0.05) between most of the values among children from the analyzed groups. There was a statistically significant difference (p < 0.001) between the EI values among girls from the two analyzed groups: at-risk (1,773.18 kcal ±  232.57) and not at-risk (2,054.00 kcal ±  191.39). Girls who did not meet the energy intake recommendations were 10.00 as likely to be in the Triad/Red-S risk group.

Conclusion

Early identification of Fat/Red-S symptoms by screening tools such as the LEAF questionnaire is important in protecting young athletes from long-term damage due to the progression of the risk factors associated with the Fat/Red-S.

Self-Reported Restrictive Eating, Eating Disorders, Menstrual Dysfunction, and Injuries in Athletes Competing at Different Levels and Sports

The purpose of this study was to investigate the prevalence of self-reported restrictive eating, current or past eating disorder, and menstrual dysfunction and their relationships with injuries. Furthermore, we aimed to compare these prevalences and associations between younger (aged 15–24) and older (aged 25–45) athletes, between elite and non-elite athletes, and between athletes competing in lean and non-lean sports. Data were collected using a web-based questionnaire. Participants were 846 female athletes representing 67 different sports. Results showed that 25%, 18%, and 32% of the athletes reported restrictive eating, eating disorders, and menstrual dysfunction, respectively. Higher rates of lean sport athletes compared with non-lean sport athletes reported these symptoms, while no differences were found between elite and non-elite athletes. Younger athletes reported higher rates of menstrual dysfunction and lower lifetime prevalence of eating disorders. Both restrictive eating (OR 1.41, 95% CI 1.02–1.94) and eating disorders (OR 1.89, 95% CI 1.31–2.73) were associated with injuries, while menstrual dysfunction was associated with more missed participation days compared with a regular menstrual cycle (OR 1.79, 95% CI 1.05–3.07). Our findings indicate that eating disorder symptoms and menstrual dysfunction are common problems in athletes that should be managed properly as they are linked to injuries and missed training/competition days.

Eating Disorders in the Adolescent Patient

Eating disorders such as anorexia nervosa, female athlete triad, bulimia nervosa, obesity, and binge eating initially emerge during adolescence. These disorders are present primarily in females, but males may also present with these conditions. Dentistry has a pivotal role in the management of patients with such diet-related disorders. Because dentists examine their patients at frequent intervals and may be the health care professionals with whom patients feel more comfortable discussing eating disorders, dentists must have knowledge of the etiology, diagnostic criteria, systemic effects, and intraoral manifestations of eating disorders. In addition, the dental professional may be the first health care provider to identify the condition and refer the patient appropriately to medical colleagues for subsequent treatment. This chapter provides dentists with current and relevant information to recognize, diagnose, and integrate dental treatment for their adolescent patients who may exhibit manifestations of an eating disorder.

Prevalence of Surrogate Markers of Relative Energy Deficiency in Male Norwegian Olympic-Level Athletes

The syndrome of Relative Energy Deficiency in Sport (RED-S) includes wide-ranging effects on physiological and psychological functioning, performance, and general health. However, RED-S is understudied among male athletes at the highest performance levels. This cross-sectional study aimed to investigate surrogate RED-S markers prevalence in Norwegian male Olympic-level athletes. Athletes (n = 44) aged 24.7 ± 3.8 years, body mass 81.3 ± 15.9 kg, body fat 13.7% ± 5.8%, and training volume 76.1 ± 22.9 hr/month were included. Assessed parameters included resting metabolic rate (RMR), body composition, and bone mineral density by dual-energy X-ray absorptiometry and venous blood variables (testosterone, free triiodothyronine, cortisol, and lipids). Seven athletes (16%) grouped by the presence of low RMR (RMRratio < 0.90) (0.81 ± 0.07 vs. 1.04 ± 0.09, p < .001, effect size 2.6), also showed lower testosterone (12.9 ± 5.3 vs. 19.0 ± 5.3 nmol/L, p = .020) than in normal RMR group. In low RMRratio individuals, prevalence of other RED-S markers (-subclinical-low testosterone, low free triiodothyronine, high cortisol, and elevated low-density lipoprotein) was (N/number of markers): 2/0, 2/1, 2/2, 1/3. Low bone mineral density (z-score < -1) was found in 16% of the athletes, all with normal RMR. Subclinical low testosterone and free triiodothyronine levels were found in nine (25%) and two (5%) athletes, respectively. Subclinical high cortisol was found in 23% of athletes while 34% had elevated low-density lipoprotein cholesterol levels. Seven of 12 athletes with two or more RED-S markers had normal RMR. In conclusion, this study found that multiple RED-S markers also exist in male Olympic-level athletes. This highlights the importance of regular screening of male elite athletes, to ensure early detection and treatment of RED-S.

Prevalence of disordered eating, eating disorders and risk of low energy availability in professional, competitive and recreational female athletes based in the United Kingdom

Eating disorders (ED), disordered eating (DE) and low energy availability (LEA) can be detrimental to health and performance. Previous studies have independently investigated the prevalence of ED, DE or LEA; however, few combined methods have identified risk within female athletes. The aim of this study was to identify the prevalence of ED, DE and LEA in UK-based female athletes and investigate whether associations exist between age, competition level and primary sport. The Female Athlete Screening Tool (FAST) and Low Energy Availability in Females Questionnaire (LEAF-Q) were used in a cross-sectional study design. A total of 112 responses eligible for analysis were received. A total of 16%, 44% and 53% of female athletes were at risk of ED (FAST: >94), DE and LEA, respectively. Competition level (recreational, competitive or professional athletes; fishers, p ≤ 0.05) influenced and was a predictor of FAST (R²= 0.076, F_(1,110) = 10.067, p ≤ 0.05, variance inflation value; VIF = 1.0) whereas age influenced (age: H₍₂₎ = 13.128, p ≤ 0.05), and was a predictor (R² = 0.144, F_(2,109) =  9.170, p ≤ 0.05, VIF = 1.0) of LEAF-Q. A positive correlation was observed between FAST and LEAF-Q scores (R = 0.496, p ≤ 0.05). Age and competition level may be predicting risk factors of ED/DE and LEA within female athletes; however, further research is required to support the findings of this present study.

Physiological Characteristics of Female Soccer Players and Health and Performance Considerations: A Narrative Review

Female soccer has seen a substantial rise in participation, as well as increased financial support from governing bodies over the last decade. Thus, there is an onus on researchers and medical departments to develop a better understanding of the physical characteristics and demands, and the health and performance needs of female soccer players. In this review, we discuss the current research, as well as the knowledge gaps, of six major topics: physical demands, talent identification, body composition, injury risk and prevention, health and nutrition. Data on female talent identification are scarce, and future studies need to elucidate the influence of relative age and maturation selection across age groups. Regarding the physical demands, more research is needed on the pattern of high-intensity sprinting during matches and the contribution of soccer-specific movements. Injuries are not uncommon in female soccer players, but targeting intrinsically modifiable factors with injury prevention programmes can reduce injury rates. The anthropometric and physical characteristics of female players are heterogeneous and setting specific targets should be discouraged in youth and sub-elite players. Menstrual cycle phase may influence performance and injury risk; however, there are few studies in soccer players. Nutrition plays a critical role in health and performance and ensuring adequate energy intake remains a priority. Despite recent progress, there is considerably less research in female than male soccer players. Many gaps in our understanding of how best to develop and manage the health and performance of female soccer players remain.

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.

Energy Availability with or without Eating Disorder Risk in Collegiate Female Athletes and Performing Artists

CONTEXT

Female athletes/performing artists can present with low energy availability (LEA) either through unintentional (e.g., inadvertent undereating) or intentional methods (e.g., eating disorder [ED]). While LEA and ED risk have been examined independently, little research has examined these simultaneously. Awareness of LEA with or without ED risk may provide clinicians with innovative prevention and intervention strategies.

OBJECTIVE

To examine LEA with or without ED risk (e.g., eating attitudes, pathogenic behaviors) in female collegiate athletes/performing artists.

DESIGN

Cross-sectional and descriptive.

SETTING

Free-living in sport-specific settings.

PARTICIPANTS

Collegiate female athletes/performing artist (n=121; age: 19.8±2.0 years; height: 168.9±7.7 cm; weight: 63.6±9.26 kg) in equestrian (n=28), volleyball (n=12), softball (n=17), beach volleyball (n=18), ballet (n=26) and soccer (n=20) participated in this study.

MAIN OUTCOME MEASURES

Anthropometric measurements (height, weight, body composition), resting metabolic rate, energy intake, total daily energy expenditure, exercise energy expenditure, Eating Disorder Inventory-3 (EDI-3), and EDI-3 Symptom Checklist were assessed. Chi-square analysis examined differences between LEA and sport type, LEA and ED risk, ED risk and sport type, and pathogenic behaviors and sport type.

RESULTS

Female athletes/performing artists (81%; n=98) displayed LEA and significant differences were found between LEA and sport type (χ25=43.8, P<.01). Female athletes/performing artists (76.0%; n=92) presented with ED risk with no significant difference between ED risk and sport. EDI-3 Symptom Checklist revealed 61.2% (n=74) engaged in pathogenic behaviors, with dieting the most common (51.2%; n=62). Athletes/performing artist displayed LEA with ED risk (76.0%; n=92). No significant differences were found between LEA with ED risk and sport. Softball was the highest with 82.4% (n=14) reporting LEA with ED risk followed by ballet (76%; n=19).

CONCLUSION

Our results suggest a large proportion of collegiate female athletes/performing artists are at risk for LEA with ED risk, thus warranting education, identification, prevention, and intervention strategies relative to fueling for performance.

Injuries in female and male elite Korean rowing athletes: an epidemiological study

This study aimed to determine the patterns of injury associated with training activities in elite South Korean rowing athletes training for the Olympic Games. Data were prospectively collected between 2010 and 2019 at the Korea National Training Center in South Korea. Three sports medicine doctors assessed athletes, and the data were stratified according to sex, rowing style, weight class, site of injury, and severity of injury. The groups were compared using the c 2 test. The 95 % confidence interval with Poisson rates and exact Poisson test were used for comparison of rates. In total 514 injuries were recorded during the study period, with an average of 2.86 injuries per athlete annually; among these, over half (57.8 %) were mild injuries. Most injuries occurred in the lower extremities (42.0 %), followed by the trunk (30.2 %), the upper extremities (24.9 %), and the head and neck area (2.9 %). Weight class was significantly associated with severity of injury in all rowing athletes (p < 0.001), for both male and female rowing athletes (p = 0.006 and p = 0.014, respectively). Lightweight male athletes demonstrated higher incidence rate of injury than open-weight male athletes (p < 0.001). On the contrary, lightweight female athletes demonstrated lower incidence rates of injury than open-weight female athletes (p < 0.001). These findings on the incidence of training injuries and patterns based on rowing styles, sexes, and weight classes may elucidate the circumstances leading to injuries in elite Korean rowing athletes. Furthermore, these findings may contribute to the development of programs to enhance athletic performance and reduce the incidence of sports injuries.

Low energy availability: history, definition and evidence of its endocrine, metabolic and physiological effects in prospective studies in females and males

Energy availability (EA) is defined as the amount of dietary energy available to sustain physiological function after subtracting the energetic cost of exercise. Insufficient EA due to increased exercise, reduced energy intake, or a combination of both, is a potent disruptor of the endocrine milieu. As such, EA is conceived as a key etiological factor underlying a plethora of physiological dysregulations described in the female athlete triad, its male counterpart and the Relative Energy Deficiency in Sport models. Originally developed upon female-specific physiological responses, this concept has recently been extended to males, where experimental evidence is limited. The majority of data for all these models are from cross-sectional or observational studies where hypothesized chronic low energy availability (LEA) is linked to physiological maladaptation. However, the body of evidence determining causal effects of LEA on endocrine, and physiological function through prospective studies manipulating EA is comparatively small, with interventions typically lasting ≤ 5 days. Extending laboratory-based findings to the field requires recognition of the strengths and limitations of current knowledge. To aid this, this review will: (1) provide a brief historical overview of the origin of the concept in mammalian ecology through its evolution of algebraic calculations used in humans today, (2) Outline key differences from the ‘energy balance’ concept, (3) summarise and critically evaluate the effects of LEA on tissues/systems for which we now have evidence, namely: hormonal milieu, reproductive system endocrinology, bone metabolism and skeletal muscle; and finally (4) provide perspectives and suggestions for research upon identified knowledge gaps.

Lower Trabecular Bone Score and Spine Bone Mineral Density Are Associated With Bone Stress Injuries and Triad Risk Factors in Collegiate Athletes

INTRODUCTION

Determinants of bone health and injury are important to identify in athletes. Bone mineral density (BMD) is commonly measured in athletes with Female Athlete Triad (Triad) risk factors; the trabecular bone score (TBS) has been proposed to predict fracture risk independent of BMD. Evaluation of TBS and spine BMD in relation bone stress injury (BSI) risk has not been studied in female collegiate athletes.

OBJECTIVE

We hypothesized that spine BMD and TBS would each independently predict BSI and that the combined measures would improve injury prediction in female collegiate athletes. We also hypothesized that each measure would be correlated with Triad risk factors.

DESIGN

Retrospective cohort.

SETTING

Academic Institution.

METHODS

Dual energy x-ray absorptiometry (DXA) of the lumbar spine was used to calculate BMD and TBS values. Chart review was used to identify BSI that occurred after the DXA measurement and to obtain Triad risk factors. We used logistic regression to examine the ability of TBS and BMD alone or in combination to predict prospective BSI.

RESULTS

Within 321 athletes, 29 (9.0%) sustained a BSI after DXA. BMD and TBS were highly correlated (Pearson correlation r = 0.62, P < .0001). Spine BMD and TBS had similar ability to predict BSI; the C-statistic and 95% confidence intervals were 0.69 (0.58 to 0.81) for spine BMD versus 0.68 (0.57 to 0.79) for TBS. No improvement in discrimination was observed with combined BMD + TBS (C-statistic 0.70, 0.59 to 0.81). Both TBS and BMD predicted trabecular-rich BSI (defined as pelvis, femoral neck, and calcaneus) better than cortical-rich BSI. Both measures had similar correlations with Triad risk factors.

CONCLUSION

Lower BMD and TBS values are associated with elevated risk for BSI and similar correlation to Triad risk factors. TBS does not improve prediction of BSI. Collectively, our findings suggest that BMD may be a sufficient measure of skeletal integrity from DXA in female collegiate athletes.

A comparison of the metabolic effects of sustained strenuous activity in polar environments on men and women

This study investigates differences in pre- to post-expedition energy expenditure, substrate utilisation and body composition, between the all-male Spear17 (SP-17) and all-female Ice Maiden (IM) transantarctic expeditions (IM: N = 6, 61 days, 1700 km; SP-17: N = 5, 67 days, 1750 km). Energy expenditure and substrate utilisation were measured by a standardised 36 h calorimetry protocol; body composition was determined using air displacement plethysmography. Energy balance calculation were used to assess the physical challenge. There was difference in the daily energy expenditure (IM: 4,939 kcal day⁻¹; SP-17: 6,461 kcal day⁻¹, p = 0.004); differences related to physical activity were small, but statistically significant (IM = 2,282 kcal day⁻¹; SP-17 = 3,174 kcal day⁻¹; p = 0.004). Bodyweight loss was modest (IM = 7.8%, SP-17 = 6.5%; p > 0.05) as was fat loss (IM = 30.4%, SP-17 = 40.4%; p > 0.05). Lean tissue weight change was statistically significant (IM = − 2.5%, SP-17 = + 1.0%; p = 0.05). No difference was found in resting or sleeping energy expenditure, normalised to lean tissue weight (p > 0.05); nor in energy expenditure when exercising at 80, 100 and 120 steps min⁻¹, normalised to body weight (p > 0.05). Similarly, no difference was found in the change in normalised substrate utilisation for any of the activities (p > 0.05). Analysis suggested that higher daily energy expenditures for the men in Spear-17 was the result of higher physical demands resulting in a reduced demand for energy to thermoregulate compared to the women in Ice Maiden. The lack of differences between men and women in the change in energy expenditure and substrate utilisation, suggests no sex difference in response to exposure to extreme environments.

Female Athlete Triad Coalition cumulative risk assessment tool: proposed alternative scoring strategies

We (i) identified alternative scoring strategies for the Female Athlete Triad Coalition cumulative risk assessment (CRA) tool to be utilized when particular risk factors (bone mineral density (BMD), oligomenorrhea/amenorrhea) cannot be determined; (ii) objectively defined dietary restriction for use in the CRA tool; and (iii) explored proxy measures of energy deficiency. This cross-sectional investigation of exercising women (n = 166) utilized an existing database derived from multiple studies designed to assess health, exercise, and menstrual function. Data from the screening/baseline period of each study included: anthropometrics, dual-energy X-ray absorptiometry, disordered eating questionnaires, descriptive data, and proxy measures of energy deficiency (total triiodothyronine (TT₃) and ratio of measured-to-predicted resting metabolic rate (mRMR/pRMR)). Substituting delayed menarche for BMD was the best-fit replacement resulting in 15 (9%) participants being categorized in different clearance categories. When menstrual status cannot be assessed, such as during hormonal contraceptive use, low energy availability (EA) determined using self-report and disordered eating questionnaires was the best substitution, resulting in 34 (20%) participants being categorized in different clearance categories. Based on original clearance categorizations, the provisional group had lower TT₃ (78.3 ± 2.2 ng/dL; 92.7 ± 2.7 ng/dL) and Harris-Benedict mRMR/pRMR (0.85 ± 0.01; 0.90 ± 0.01) than the full group. Until an updated risk assessment tool is developed, delayed menarche can substitute for low BMD and low EA for oligomenorrhea/amenorrhea. Novelty This investigation addresses previous limitations of the Triad CRA tool. Disordered eating questionnaires can be used to objectively identify dietary restriction for the low EA risk factor. When a risk factor cannot be assessed, delayed menarche can substitute for low BMD and low EA for oligomenorrhea/amenorrhea.

Geometric and "True" Densitometric Characteristics of Bones in Athletes with Stress Fracture and Menstrual Disturbances: A Systematic Review

BACKGROUND

Stress fractures can lead to short- and long-term consequences, impacting participation in sport and general health. Recognizing which skeletal characteristics render bones susceptible to stress fracture may aid stress-fracture prevention. Menstrual disturbances among exercising women are a known risk factor for stress fracture; therefore, assessing skeletal commonalities between women with stress fractures and women with menstrual disturbances may increase our understanding of why menstrual disturbances put athletes at greater risk for stress fracture. Three-dimensional (3D) bone imaging tools provide detailed information about volumetric bone mineral density (vBMD) and bone structure that cannot be obtained using traditional two-dimensional (2D) techniques.

OBJECTIVES

This systematic review serves to: (1) evaluate the current literature available on vBMD, bone geometry, and bone structure in exercising women with menstrual disturbances and exercising women with stress fractures, and (2) assess the common skeletal characteristics between both conditions. Our aim is to reveal bone properties beyond 2D areal BMD that may indicate increased susceptibility to stress fracture among exercising women with menstrual disturbances.

SEARCH METHODS

A search of the PubMed/Medline database was completed in May 2018.

ELIGIBILITY CRITERIA

Eligible articles included those that reported vBMD, bone geometry, or bone structure obtained from 3D imaging techniques or estimated from 2D imaging techniques. Only studies conducted in premenopausal exercising women and girls who had a stress fracture, a menstrual disturbance, or both were included.

RESULTS

Twenty-four articles met the inclusion criteria. Bone area and cortical thickness at the tibia were identified as altered both in women with menstrual disturbances and in women with stress fractures; however, there was inconsistency in the results observed for all bone parameters. The majority of skeletal parameters of the lower extremities were not significantly different between exercising women with and without stress fractures and between those with and without menstrual disturbances.

DISCUSSION

Most studies were moderate or low quality based on study design, and only one article combined both conditions to explore vBMD and bone geometry in athletes with menstrual disturbances and a history of stress fracture. These findings highlight the need for more skeletal research on the intersection of these health conditions in exercising women. The lack of observed differences in skeletal parameters suggests that risk factors other than bone geometry and structure may be the primary causes of stress fracture in these women.

How the menstrual cycle and menstruation affect sporting performance: experiences and perceptions of elite female rugby players

OBJECTIVES

To explore athletes' past and current experiences and perceptions of the menstrual cycle in relation to its impact on sporting performance.

METHODS

15 international female rugby players participated in individual semi-structured interviews (age: 24.5±6.2 years). All interviews were recorded and transcribed verbatim, resulting in 37 376 words of text for descriptive and thematic analysis. Inter-rater reliability checks resulted in a concordance of agreement of 83%.

RESULTS

Almost all athletes (93%) reported menstrual cycle-related symptoms. Thirty-three per cent perceived heavy menstrual bleeding and 67% considered these symptoms impaired their performances. Two-thirds of athletes self-medicated to alleviate symptoms. Thematic analysis generated 262 meaning units, 38 themes, 10 categories and 4 general dimensions. The four general dimensions were: (1) symptoms: physiological and psychological menstrual cycle-related symptoms such as dysmenorrhoea, flooding, reduced energy levels, worry, distraction, fluctuating emotions and reduced motivation; (2) impact: perceived impact of menstruation on different aspects of daily lives and performance including negative and neutral responses; (3) resolution: the methods/approaches in dealing with menstruation-related concerns including accepting, or adapting and managing symptoms with self-medication or expert treatment; (4) support: available support and comfortability in discussing menstrual cycle-related issues.

CONCLUSIONS

This study provides the first in-depth insight into athlete's experiences of the menstrual cycle and perceived impact on training and competition. It highlights individual responses to menstrual 'issues' and emphasises the need for clinicians and support staff to undertake menstrual cycle profiling, monitoring and continue to develop awareness, openness, knowledge and understanding of the menstrual cycle.

Practice does not make perfect: A brief view of athletes' knowledge on the menstrual cycle and oral contraceptives

OBJECTIVES

To assess the knowledge of Australian elite female athletes surrounding the menstrual cycle and oral contraceptives.

DESIGN

Cross sectional survey.

METHODS

Australian female athletes (n=189) representing their state and/or country in their respective sport completed a questionnaire comprising questions (multiple choice and short answer) relating to the menstrual cycle and oral contraceptives. A knowledge 'score' was calculated by allocating one point for each correct answer; the highest knowledge score that could be achieved was 14. Linear regression analysis was used to identify variables that were independently associated with menstrual cycle and oral contraceptive knowledge.

RESULTS

Almost half (47.1 %) of the athletes surveyed were currently using hormonal contraception, the majority (75.3 %) of which used an oral contraceptive pill. Nevertheless, the mean knowledge score achieved by athletes on the questionnaire was 5.03±3.06, with only 8.5 % of athletes achieving a knowledge score of 10 or above. Hormonal contraceptive use and 'identifying as an individual athlete' were two factors that were significantly associated with overall knowledge score (p≤0.004), with current hormonal contraceptive users and individual athletes scoring 1.79 and 1.66 points on average higher than non-users and team sport athletes, respectively.

CONCLUSIONS

Our findings indicate that knowledge surrounding the menstrual cycle and oral contraceptives was low in most elite athletes. Further education is warranted to enable athletes to make informed decisions regarding hormonal contraception, and any educational interventions should be implemented across all athlete groups.

Disordered eating behaviours in female physique athletes

Despite substantial growth in participation rates in physique sports, little is known about the modern day female physique athlete. The extreme physique traits of successful female physique athletes suggest this population may be particularly at risk of developing disordered eating (DE). The aim of this study was to determine if female physique athletes across the main divisions of bikini, fitness, figure and bodybuilding were at risk of DE and to explore possible associated risk factors. Furthermore, we aimed to investigate differences in incidence of DE across divisions given differences in physique requirements. Female physique athletes (n = 348) were recruited using targeted methods and completed an online survey based on validated questionnaires, including the Drive for Thinness, Body Dissatisfaction, and Bulimia subscales of the Eating Disorder Inventory (EDI), Pathogenic Weight Control Measures (PWCM), and the Cognitive Dietary Restraint subscale of the Three-Factor Eating Questionnaire (TFEQ-CDR). Athletes scoring above the cut off values for one or more of the EDI subscales or engaged in at least one of the most concerning PWCM (binge eating, laxative use, and self-induced vomiting) were considered at risk of DE. Approximately half of the participants were identified with DE (46.6%), independent of division, with 27.3% exhibiting clinical and 19.3% having subclinical DE. Furthermore, approximately half (48.9%) of participants engaged in at least one of the most concerning PWCM within the past three months, with a smaller proportion (5.2%) engaging in all three PWCM. Weak but significant correlations were found between some EDI subscales and reason for sport participation, BMI and body composition goals. Drive for thinness and body dissatisfaction were positively associated with use of PWCM. In conclusion, a high proportion of female physique athletes were identified with DE, with a concerning number of athletes engaging in harmful PWCM.

The effects of a 226-km ironman triathlon race on bone turnover in amateur male triathletes

BACKGROUND

The purpose of this study was to investigate the effects of an Ironman-distance triathlon on bone metabolism.

METHODS

Nine recreational male triathletes (39.7±8.2 years old) were voluntarily recruited before a 226-km Ironman triathlon race. Baseline blood samples were collected >1 hour before race. Serial post-race blood sampling time points included immediately (0hr), 1 hour (1hr), 1 day (d), 3 d, and 5 d after the Ironman race.

RESULTS

Serum muscle damage markers, serum myoglobin, creatine kinase (CK) and lactate dehydrogenase (LDH) revealed significant post-race peak values immediately, 1hr and 1d after the race, respectively. Except for the marginally higher serum CK and myoglobin at 5d (P=0.01~0.05), all post-race serum levels of muscle damage markers were significantly higher than baseline levels (P<0.01). Serum phosphorus values were significantly higher immediately (0hr) after the Ironman race. Serum osteocalcin, an index specific to bone formation, showed a significant decrease at time points 0hr and 1hr, but a significant increase 1 day after (P<0.01) and a marginal increase 3 and 5 days after (P=0.01~0.05) the race. No difference was shown in type I collagen C-telopeptide (CTX-1), a bone resorption marker. Pearson's correlation between serum osteocalcin and CTX-1 was done at each time point, and significant correlation was shown on the 5th d after the race (r=0.591, P<0.05).

CONCLUSIONS

An Ironman-distance contest induces a bone-formative-favoring turnover during the post-race period for amateur male triathletes.

"Despite being an athlete, I am also a human-being": Male elite gymnasts' reflections on food and body image

Our aim was to investigate the prevalence of symptoms related to eating disorders, disordered eating and body image perception, and attitudes toward eating in a group of elite male artistic gymnastics. Seventeen athletes took part in this quali-quantitative, cross-sectional study. Presence of eating disorders symptoms, and body image perception and satisfaction were assessed using validated questionnaires. Focus groups were held to discuss their attitudes toward eating and body image perception in more detail. Little to no evidence of symptoms consistent with eating disorders was observed, and this was supported by the qualitative data. However, some concerning practices and attitudes were described. Negative emotional eating cycles appeared prevalent (e.g. feelings of anger, stress and anxiety creating a desire to eat "junk foods", followed by guilt and regret). Body image perception and attitudes toward body weight's influence on performance varied widely. Some athletes expressed a desire to lose weight and believed that this would positively impact their performance, while others believed weight to be irrelevant and focused on feeling strong and vital. Athletes believed their female counterparts experienced far greater pressure to maintain low body weight and described some very concerning practices. We conclude that eating disorders and disordered eating did not appear to be prevalent among these elite male artistic gymnastics. However, some concerning attitudes and practices were observed and should be addressed with nutritional support programmes encompassing psychological and behavioural aspects of eating. These programmes should be extended to support staff and significant others, in addition to athletes.