Nine-month nutritional intervention improves restoration of menses in young female athletes and ballet dancers

The Role of Musculoskeletal Training During Return to Performance Following Relative Energy Deficiency in Sport

BACKGROUND

Relative energy deficiency in sport (REDs) is a condition that is associated with negative health and performance outcomes in athletes. Insufficient energy intake relative to exercise energy expenditure, resulting in low energy availability, is the underlying cause, which triggers numerous adverse physiological consequences including several associated with musculoskeletal (MSK) health and neuromuscular performance.

PURPOSE

This commentary aims to (1) discuss the health and performance implications of REDs on the skeletal and neuromuscular systems and (2) examine the role that MSK training (ie, strength and plyometric training) during treatment and return to performance following REDs might have on health and performance in athletes, with practical guidelines provided.

CONCLUSIONS

REDs is associated with decreases in markers of bone health, lean body mass, maximal and explosive strength, and muscle work capacity. Restoration of optimal energy availability, mainly through an increase in energy intake, is the primary goal during the initial treatment of REDs with a return to performance managed by a multidisciplinary team of specialists. MSK training is an effective nonpharmacological component of treatment for REDs, which offers multiple long-term health and performance benefits, assuming the energy needs of athletes are met as part of their recovery. Supervised, prescribed, and gradually progressive MSK training should include a combination of resistance training and high-impact plyometric-based exercise to promote MSK adaptations, with an initial focus on achieving movement competency. Progressing MSK training exercises to higher intensities will have the greatest effects on bone health and strength performance in the long term.

Low Body Fat Percentage and Menstrual Cycle Disorders in Female Elite Adolescent Dancers

Introduction: The menstrual cycle is an important indicator of health in female athletes. Female elite adolescent dancers are expected to control their weight while also training intensely, which can lead to menstrual disorders. This study aimed to investigate the relationship between body composition and menstrual status in female elite adolescent dancers. Methods: In total, 131 female elite adolescent dancers (age: 15.9 ± 1.5 years) were enrolled in this study. We measured the height, weight, and body fat percentage (BFP) for each participant and calculated their body mass index (BMI). We gathered information on individual menstruation patterns and the participants' menstrual cycles over the previous year using recall methods. We then compared the differences between dancers with menstrual cycle disorders and those without. Primary amenorrhea was defined as menarche occurring after the age of 15, while secondary amenorrhe was defined as experiencing fewer than 5 or no menstrual periods for at least 3 of the previous 12 months. We conducted a reliability test using the same questionnaire 2 weeks later. Statistical significance was defined as P < .05, and we calculated the effect sizes (d) and 95% confidence intervals (95% CI). Results: The average BMI and BFP were 22.6 ± 3.0% and 19.4 ± 2.2 kg/m2, respectively. Low BFP and low BMI were observed in 51 (38.6%) and 47 (35.6%) participants, respectively. Primary amenorrhea in 3 participants (2.3%) and 29 (22.1%) reported experiencing secondary amenorrhea; they had lower BFP than the dancers who did not experience amenorrhea (P = .041, 95% CI, -2.51 to -0.05). Conclusion: Female elite adolescent dancers in China may have lower BFP and menstrual problems. Given that lower BFP may contribute to the occurrence of menstruation disorders, it is essential to pay an attention to both BFP and the menstruation status in female elite adolescent dancers.

Age and menstrual cycle may be important in establishing pregnancy in female athletes after retirement from competition

BACKGROUND

Although it has been shown that amenorrhea associated with low energy availability or relative energy deficiency in sport affects body physiology in female athletes, the association between menstrual dysfunction during active sports careers and reproductive function after retirement is not clear.

OBJECTIVE

To investigate the association between menstrual dysfunction during their active sports career and post-retirement infertility in female athletes.

METHODS

A voluntary web-based survey was aimed at former female athletes who had become pregnant and gave birth to their first child after retirement. Nine multiple-choice questions were included, on maternal age, competition levels and menstrual cycles during active sports careers, time from retirement to pregnancy, the time of resumption of spontaneous menstruation after retirement, conception method, and mode of delivery, etc. Regarding cases of primary and secondary amenorrhea among the abnormal menstrual cycle group, only those whose spontaneous menstruation had not recovered from retirement to the time of pregnancy were included in the study. The association between the presence of abnormal menstrual cycles from active sports careers to post-retirement pregnancy and the implementation of infertility treatment was evaluated.

RESULTS

The study population included 613 female athletes who became pregnant and gave birth to their first child after retiring from competitive sports. Of the 613 former athletes, the infertility treatment rate was 11.9%. The rate of infertility treatment was significantly higher in athletes with abnormal than normal menstrual cycles (17.1% vs. 10.2%, p = 0.0225). Multivariable logistic regression analysis showed that maternal age (adjusted odds ratio [OR] 1.194; 95% confidence interval [CI] 1.129, 1.262) and abnormal menstrual cycles (OR and 1.903; adjusted OR 1.105, 3.278) were the relevant factors for infertility treatment.

CONCLUSION

It was suggested that menstrual dysfunction that persist from active sports careers to post-retirement may be a factor in infertility when trying to conceive after retirement.

The effect of nutrition education sessions on energy availability, body composition, eating attitude and sports nutrition knowledge in young female endurance athletes

Nutrition knowledge plays a pivotal role in shaping dietary habits and food choices, particularly in the realm of sports nutrition. This study investigates the effects of a series of nutrition education sessions conducted by a registered dietitian on energy availability, various anthropometric measurements, eating attitudes, and sports nutrition knowledge in young female endurance athletes aged 15-18 years (football, basketball, volleyball) who engage in training for more than 10 h per week (n = 83). Participants were randomly divided into two groups with 45 individuals receiving six physical nutrition education lectures, and the remaining 38 participants receiving no nutrition education. Participants completed the low energy availability in females questionnaire (LEAF-Q), Eating Attitude Test (EAT-26), and Sports Nutrition Knowledge Questionnaire (SNKQ). Energy and nutrient intakes were evaluated through 3-day food records, while exercise energy expenditure was assessed using 3-day activity logs. All of the questionnaires were repeated after 6 months. At baseline, the prevalence of LEA among athletes was determined to be 63.8%. In the intervention group, energy availability (EA) and SNKQ scores increased, and LEAF-Q scores decreased significantly (p < 0.05). However, there was no significant change in EAT-26 scores between the two groups. Energy intake, weight, fat-free mass, and resting metabolic rate have been increased significantly in the intervention group (p < 0,05). These findings suggest that nutrition education proves beneficial in enhancing dietary intake, positively influencing body composition, and improving nutrition knowledge, ultimately contributing to increased energy availability in female athletes over the short term.

12-months of increased dietary intake does not exacerbate disordered eating-related attitudes, stress, or depressive symptoms in women with exercise-associated menstrual disturbances: The REFUEL randomized controlled trial

Disordered eating-related attitudes are a leading cause of energy deficiency and menstrual disturbances in exercising women. Although treatment recommendations include psychological counseling with increases in dietary intake, a key concern is whether increased dietary intake may exacerbate negative eating behaviors.

OBJECTIVE

To determine the effects of a 12-month nutritional intervention on eating-related attitudes and psychological characteristics in exercising women with oligomenorrhea/amenorrhea (Oligo/Amen).

METHODS

Intent-to-treat analysis of the REFUEL randomized controlled trial (#NCT00392873) in 113 exercising women (age [mean±SEM]:] 21.9 ± 0.4 yrs; BMI: 20.9 ± 0.2 kg/m²). Women were randomized to increase energy intake 20-40% above baseline energy needs (Oligo/Amen+Cal, n = 40) or maintain energy intake (Oligo/Amen Control, n = 36) while maintaining their exercise behaviors. A reference group of ovulatory women (OVref, n = 37) maintained diet and exercise behaviors. Body composition, eating attitudes, stress, and depressive symptoms were assessed at baseline and every 3 months.

RESULTS

At baseline, the Oligo/Amen groups had higher drive for thinness, cognitive restraint, and eating disorder risk than OVref group (p < 0.001). Increased energy intake led to increases in percent body fat and fat mass (p < 0.010), but not psychobehavioral outcomes, in the Oligo/Amen+Cal compared to Oligo/Amen Control group. Independent of group, cognitive restraint decreased (p < 0.001) and resilient coping increased (p < 0.007) over 12-months, while perceived stress (p = 0.143) and depressive symptoms (p = 0.344) were unchanged.

DISCUSSION

Long-term nutritional intervention consisting of modest increases in dietary intake with guidance from a registered dietician and a psychologist increases body and fat mass without increasing disordered eating-related attitudes, stress, or depressive symptoms in exercising women with Oligo/Amen.

Effects of a 16-Week Digital Intervention on Sports Nutrition Knowledge and Behavior in Female Endurance Athletes with Risk of Relative Energy Deficiency in Sport (REDs)

Female endurance athletes are considered a high-risk group for developing Relative Energy Deficiency in Sport (REDs). Due to the lack of educational and behavioral intervention studies, targeting and evaluating the effects of the practical daily management of REDs, we developed the Food and nUtrition for Endurance athletes-a Learning (FUEL) program, consisting of 16 weekly online lectures and individual athlete-centered nutrition counseling every other week. We recruited female endurance athletes from Norway (n = 60), Sweden (n = 84), Ireland (n = 17), and Germany (n = 47). Fifty athletes with symptoms of REDs and with low risk of eating disorders, with no use of hormonal contraceptives and no chronic diseases, were allocated to either the FUEL intervention (n = 32) (FUEL) or a 16-week control period (n = 18) (CON). All but one completed FUEL, while 15 completed CON. We found strong evidence for improvements in sports nutrition knowledge, assessed via interviews, and moderate to strong evidence in the ratings concerning self-perceived sports nutrition knowledge in FUEL versus CON. Analyses of the seven-day prospective weighed food record and questions related to sports nutrition habits, suggested weak evidence for improvements in FUEL versus CON. The FUEL intervention improved sports nutrition knowledge and suggested weak evidence for improved sports nutrition behavior in female endurance athletes with symptoms of REDs.

Intervention in professional dance students to increase mental health- and nutrition literacy: A controlled trial with follow up

Introduction

There is a need to change the culture within the art of dance, as it has been associated with injuries and mental health consequences. This study evaluates an intervention designed to increase mental health literacy, enhance nutritional knowledge, reduce symptoms and effects of low energy availability, and strengthen understanding of sports nutrition and recovery strategies, in dance students of mixed genders.

Material and methods

A total of 125 dance students received three workshops, with 39 arts and crafts students serving as references. The results were evaluated by the Eating Disorder Examination questionnaire, the Low Energy Availability in Females questionnaire, the Hopkins Symptom Check List, and questions on mental health literacy, sports nutrition, and recovery knowledge.

Results

Dance students achieved sustained improvements in mental health and nutrition knowledge and temporary improvements in driven exercise (i.e., performing exercise because of a compulsive drive). No other benefits were identified from the intervention.

Conclusion

Our findings indicate the need for an ongoing education program to reduce the occurrence and development of negative mental health outcomes and low energy availability in professional dance students. Such approaches may not only improve the mental health of dance students but also potentially prevent the high frequency of injuries.

Menstrual cycle changes and mental health states of women hospitalized due to COVID-19

Purpose

Many studies have evaluated the impact of the COVID-19 pandemic on women’s mental health and menstrual changes. However, most of these studies only included nonhospitalized COVID-19 patients, while information on hospitalized women is very limited. Thus, this study aimed to examine the mental health status and menstrual changes in hospitalized female COVID-19 patients.

Methods

A survey was administered to female COVID-19 patients in the isolation ward of a national referral hospital in Indonesia between January and August 2021, and the women were followed up 3 months after discharge. The survey evaluated menstrual patterns and mental health using the Self Reporting Questionnaire-29 (SRQ-29).

Results

The study enrolled 158 female patients. There was an increase in patients who had a cycle length of > 32 or < 24 days, and significant increases in menstrual irregularity and heavy menstrual bleeding were noted. Overall, 37.3% of the patients reported a change in menstrual pattern after infection with COVID-19. Based on SRQ-29 scores, 32.3% of the women had neurotic symptoms, 12.7% had psychotic symptoms, and 38.0% had symptoms of posttraumatic stress disorder. Patients with symptoms of mental health disorders were twice as likely to report a menstrual change (OR 2.17, 95% CI 1.12–4.22; p = 0.021).

Conclusion

Menstrual changes and increased symptoms of mental health disorders occur in hospitalized female COVID-19 patients. The length of isolation was the key factor affecting overall menstrual changes and mental health in hospitalized female COVID-19 patients.

Management of Stress Fractures in Ballet

Stress fractures are highly prevalent in ballet dancers and lead to notable time loss from dancing. Nutritional status, body composition, bone mineral density, and rate of increase in activity are among the components that influence risk for stress fractures. Proper evaluation and management of stress fractures is essential including a review of the causative factors involved in each stress injury. The purpose of this article was to summarize current evidence for risk factors involved in dancers' stress fractures to optimize prevention and treatment. Identified associated factors include low energy availability, low bone mineral density, low fat body composition, abnormal lower extremity biomechanics, genetic factors, and high training loads.

Fat-Free Mass Using Bioelectrical Impedance Analysis as an Alternative to Dual-Energy X-Ray Absorptiometry in Calculating Energy Availability in Female Adolescent Athletes

Energy availability (EA) is calculated by subtracting exercise energy expenditure from energy intake, adjusted for fat-free mass (FFM) obtained using accurate methods, such as dual-energy X-ray absorptiometry (DXA). Unlike DXA, the bioelectrical impedance analysis (BIA) is low in cost, simple and easy to carry out. This study aimed to test the concordance between the calculation of EA using FFM values from four BIA predictive equations and FFM obtained using DXA in female adolescent athletes (n = 94), recruited via social media. Paired Student's t test, Wilcoxon test, Lin's concordance correlation coefficient, root mean square error, limits of agreement, and mean absolute percentage error were used to evaluate agreement between the FFM values obtained by the four SF-BIA predictive equations and DXA. Regression linear analysis was used to determine the relation between FFM values obtained using DXA and the BIA predictive equations. Standardized residuals of the FFM and EA were calculated considering DXA values as reference. The most appropriate model for the FFM (limits of agreement = 4.0/-2.6 kg, root mean square error = 1.9 kg, mean absolute percentage error = 4.34%, Lin's concordance correlation coefficient = .926) and EA (limits of agreement = 2.51/4.4 kcal·kg FFM-1·day-1, root mean square error = 1.8 kcal·kg FFM-1·day-1, mean absolute percentage error 4.24%, Lin's concordance correlation coefficient = .992) was the equation with sexual maturity as a variable, while the equation with the greatest age variability was the one with the lowest agreement. FFM-BIA predictive equations can be used to calculate EA of female adolescent athletes. However, the equation should be chosen considering sex, age, and maturation status. In the case of athletes, researchers should use equations developed for this group.

Dietary Iron and the Elite Dancer

Dancers are an athlete population at high risk of developing iron deficiency (ID). The aesthetic nature of the discipline means dancers potentially utilise dietary restriction to meet physique goals. In combination with high training demands, this means dancers are susceptible to problems related to low energy availability (LEA), which impacts nutrient intake. In the presence of LEA, ID is common because of a reduced mineral content within the low energy diet. Left untreated, ID becomes an issue that results in fatigue, reduced aerobic work capacity, and ultimately, iron deficient anaemia (IDA). Such progression can be detrimental to a dancer’s capacity given the physically demanding nature of training, rehearsal, and performances. Previous literature has focused on the manifestation and treatment of ID primarily in the context of endurance athletes; however, a dance-specific context addressing the interplay between dance training and performance, LEA and ID is essential for practitioners working in this space. By consolidating findings from identified studies of dancers and other relevant athlete groups, this review explores causal factors of ID and potential treatment strategies for dancers to optimise absorption from an oral iron supplementation regime to adequately support health and performance.

Female Hyperandrogenism in Elite Sports and the Athletic Triad

Essential hyperandrogenism seems to be overrepresented in female elite athletes. This applies to mild forms such as polycystic ovary syndrome, as well as rare differences/disorders of sex development (DSD). The reason is likely a selection bias since there is increasing evidence that androgens are beneficial for athletic performance by potent anabolic effects on muscle mass and bone mass, and stimulation of erythropoiesis. XY DSD may cause a greatly increased production of testosterone in the male range, that is, 10 to 20 times higher than the normal female range. The established regulations concerning the eligibility of female athletes with severe hyperandrogenism to compete in the female classification remain controversial. The most common cause of menstrual disorders in female athletes, however, is probably an acquired functional hypothalamic disturbance due to energy deficiency in relation to energy expenditure, which could lead to low bone mineral density and increased risk of injury. This condition is particularly common in endurance and esthetic sports, where a lean body composition is considered an advantage for physical performance. It is important to carefully evaluate endocrine disturbances and menstrual disorders in athletes since the management should be specific according to the underlying cause.

Randomised controlled trial of the effects of increased energy intake on menstrual recovery in exercising women with menstrual disturbances: the 'REFUEL' study

STUDY QUESTION

Does increased daily energy intake lead to menstrual recovery in exercising women with oligomenorrhoea (Oligo) or amenorrhoea (Amen)?

SUMMARY ANSWER

A modest increase in daily energy intake (330 ± 65 kcal/day; 18 ± 4%) is sufficient to induce menstrual recovery in exercising women with Oligo/Amen.

WHAT IS KNOWN ALREADY

Optimal energy availability is critical for normal reproductive function, but the magnitude of increased energy intake necessary for menstrual recovery in exercising women, along with the associated metabolic changes, is not known.

STUDY DESIGN, SIZE, DURATION

The REFUEL study (trial # NCT00392873) is the first randomised controlled trial to assess the effectiveness of 12 months of increased energy intake on menstrual function in 76 exercising women with menstrual disturbances. Participants were randomised (block method) to increase energy intake 20-40% above baseline energy needs (Oligo/Amen + Cal, n = 40) or maintain energy intake (Oligo/Amen Control, n = 36). The study was performed from 2006 to 2014.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants were Amen and Oligo exercising women (age = 21.0 ± 0.3 years, BMI = 20.8 ± 0.2 kg/m2, body fat = 24.7 ± 0.6%) recruited from two universities. Detailed assessment of menstrual function was performed using logs and measures of daily urinary ovarian steroids. Body composition and metabolic outcomes were assessed every 3 months.

MAIN RESULTS AND THE ROLE OF CHANCE

Using an intent-to-treat analysis, the Oligo/Amen + Cal group was more likely to experience menses during the intervention than the Oligo/Amen Control group (P = 0.002; hazard ratio [CI] = 1.91 [1.27, 2.89]). In the intent-to-treat analysis, the Oligo/Amen + Cal group demonstrated a greater increase in energy intake, body weight, percent body fat and total triiodothyronine (TT3) compared to the Oligo/Amen Control group (P < 0.05). In a subgroup analysis where n = 22 participants were excluded (ambiguous baseline menstrual cycle, insufficient time in intervention for menstrual recovery classification), 64% of the Oligo/Amen + Cal group exhibited improved menstrual function compared with 19% in the Oligo/Amen Control group (χ2, P = 0.001).

LIMITATIONS, REASONS FOR CAUTION

While we had a greater than expected dropout rate for the 12-month intervention, it was comparable to other shorter interventions of 3-6 months in duration. Menstrual recovery defined herein does not account for quality of recovery.

WIDER IMPLICATIONS OF THE FINDINGS

Expanding upon findings in shorter, non-randomised studies, a modest increase in daily energy intake (330 ± 65 kcal/day; 18 ± 4%) is sufficient to induce menstrual recovery in exercising women with Oligo/Amen. Improved metabolism, as demonstrated by a modest increase in body weight (4.9%), percent body fat (13%) and TT3 (16%), was associated with menstrual recovery.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by the U.S. Department of Defense: U.S. Army Medical Research and Material Command (Grant PR054531). Additional research assistance provided by the Penn State Clinical Research Center was supported by the National Center for Advancing Translation Sciences, National Institutes of Health, through Grant UL1 TR002014. M.P.O. was supported in part by the Loretta Anne Rogers Chair in Eating Disorders at University of Toronto and University Health Network. All authors report no conflict of interest.

TRIAL REGISTRATION NUMBER

NCT00392873.

TRIAL REGISTRATION DATE

October 2006.

DATE OF FIRST PATIENT’S ENROLMENT

September 2006.

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.

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.

The effectiveness of nutrition education programmes on improving dietary intake in athletes: a systematic review

Nutrition education programmes for athletes aim to enhance nutrition knowledge and more importantly support positive dietary change to enhance performance, health and well-being. This systematic review assessed changes in the dietary intakes of athletes in response to nutrition education programmes. A search was conducted which included studies providing quantitative dietary intake assessment of athletes of any calibre aged between 12 and 65 years in response to a nutrition education programme. Standardised differences (effect sizes) were calculated (when possible) for each dietary parameter. The search yielded 6285 papers with twenty-two studies (974 participants (71·9 % female)) eligible for inclusion. Studies described athletes competing at high school (n 3) through to college level or higher (n 19). Study designs were either single arm with an intervention-only group (twelve studies; n 241) or double arm including an intervention and control group (ten studies; n 689). No control groups received an alternative or ‘sham’ intervention. Face-to-face lectures (9/22) and individual nutrition counselling (6/22) were the most common education interventions. Non-weighed, 3-d diet records (10/22) were the most frequently utilised dietary assessment method. Although 14/22 studies (n 5 single and n 9 double) reported significant change in at least one nutrition parameter, dietary changes were inconsistent. Poor study quality and heterogeneity of methods prohibit firm conclusions regarding overall intervention success or superior types of educational modalities. Of note, carbohydrate intakes ‘post-intervention’ when assessed often failed to meet recommended guidelines (12/17 studies). Given the substantial investment made in nutrition education interventions with athletes, there is a need for well-designed and rigorous research to inform future best practice.

Higher-protein intake improves body composition index in female collegiate dancers

Aesthetic athletes strive to attain an ideal body image and the physical demands placed on dancers make their body composition and fitness equally as important as their technique. Body composition has shown positive changes in response to increased protein intake and may improve aesthetics of dance performance. The purpose of this study was to determine the extent to which supplemental whey protein (PRO) would improve body composition in female collegiate dancers compared with an isocaloric placebo (PLA). Twenty-one (age, 19.6 ± 1.4 years) female collegiate dancers were randomly assigned to consume PRO or PLA (25 g, 3×/day) for 12 weeks. Laboratory testing at weeks 0, 6, and 12 included 24-h urine collection, body composition (dual-energy X-ray absorptiometry), resting metabolic rate, and performance. Data were reported as means ± SD. Significance was accepted at p < 0.05. Body weight, fat mass, and lean soft tissue did not change between groups or over time. Body composition index (BCI = [(LSTpost− LSTpre) + (FMpre− FMpost)]; where LST is lean soft tissue, FM is fat mass, pre is pre-intervention, and post is post-intervention) significantly improved over time in PRO (+0.6 ± 1.9) but not PLA (−1.8 ± 3.1; p = 0.048); however, neither group demonstrated changes in laboratory performance tests. Protein supplementation for 12 weeks significantly improved BCI and provided a simple way to improve the diet in female collegiate dancers.

Novelty Twelve weeks of protein supplementation does not change body weight in female collegiate dancers. BCI improves following protein supplementation in female collegiate dancers.

Case Study: Resumption of Eumenorrhea in Parallel With High Training Load After 4 Years of Menstrual Dysfunction: A 5-Year Follow-Up of an Elite Female Cyclist

The female athlete triad is a condition where low energy availability is typically observed together with menstrual dysfunction and/or low bone mineral density. How this condition affects maximal work capacity in endurance athletes is not clear, and the recovery time course of menses with increased energy availability with concomitant high training load is unknown. This case study of an amenorrheic elite road cyclist reports resumption of normal menstrual function after weight gain during a 5-year period (2014–2019), while engaged in high training load and competition. The athlete ( 3.54 L/min, 64 ml·min−1·kg−1, aerobic peak power output 300 W, 5.4 W/kg) reported amenorrhea (2013–2015) and oligomenorrhea (2015–2018). Training load increased from 2014 to 2019 (584–818 hr/year and 26,707–41,945 training stress score/year). Regular menses (every 23–35 days) resumed in June 2018, ∼5–6 months after a weight gain episode. During the period of menstrual dysfunction, body mass was 51.3 ± 2.25 kg (mean ± 95% confidence limit) and fat percentage was 19% (dual-energy X-ray absorptiometry, 2016), and after weight gain, body mass was 56.8 ± 2.63 kg and fat percentage was 25% (dual-energy X-ray absorptiometry, 2019). Crank-based power meter data showed absolute mean maximal power (in watts) improvement over the 5 s to 4 hr range through the 2014–2019 period, while relative mean maximal power (in watts per kilogram) likely peaked in the 2015–2016 season for 5 min, 20 min, and 30 min, but remained mostly unchanged across seasons. Results suggest that (a) the best relative power output associated with aerobic capacity (5 min to 1 hr) can be achieved during menstrual dysfunction, (b) high performance achieved despite an increase in body mass, and (c) resumption of menses is achievable while maintaining high training loads when coupled with high energy availability.

Menstrual disorders in amateur dancers

Background

Rigorous exercise undertaken by young girls, combined with a negative energetic balance, is related to substantial physiological changes in a competitor’s body, often leading to hormonal imbalance manifested by: delayed puberty, delayed menstruation, menstrual disorders, and even long-term secondary amenorrhoea. Very lean competitors, with insufficient body fat content, are not capable of maintaining oestrogen production at an optimal level, which results in hypothalamic-pituitary-gonadal axis abnormalities and menstrual disorders. Studies involving research on menstrual disorders in amateur dancers are scarce. Therefore, the aim of the study was to investigate whether menstrual disorders are present among young amateur dancers.

Methods

The study involved 233 females of a mean age of 22.1 years (SD ± 4.9), training amateur ballroom dancing. The questionnaire included questions regarding the regularity of the menstrual cycle, including the absence of a menstrual period, causes of menstrual disorders and breakthrough bleeding.

Results

Menstrual disorders following a period of regular menstruation were reported by 132 (56.7%) of ballroom dancers. In 105 (79.5%), the absence of a menstrual period lasted for less than 3 months, in 18 (13.6%) it persisted for 3 up to 6 months, while in 9 (6.8%) it lasted for over 6 months.

Conclusions

The research conducted concluded that with an increased number of hours spent in training by amateur dancers, there was a statistically significant increase in the chance for menstrual disorders; the more training sessions per week there were, the longer the breaks in menstruation were noted.

Electronic supplementary material

The online version of this article (10.1186/s12905-019-0779-1) contains supplementary material, which is available to authorized users.

Iron status at opposite ends of the menstrual function spectrum

OBJECTIVES

Although exercising women are at high risk of poor iron status, it is unknown how non-pathological, physiological menstrual function affects iron status. As such, this study investigates the association between menstrual function and iron status in exercising women with amenorrhea and exercising women with ovulatory, eumenorrheic menstrual cycles.

DESIGN

Cross-sectional analysis of iron depletion prevalence, iron status indices, exercise parameters, and diet composition.

METHODS

Women aged 18-35 years performing at least 2 h per week of aerobic exercise were recruited. Women with amenorrhea (AMEN) were defined by the absence of menses for at least 90 days or less than 6 menses in the past 12 months (n = 82). Women with ovulatory, eumenorrheic menstrual cycles (OvEU) were defined by the presence of ovulatory cycles of 26-35 days in length for the past 6 months (n = 109). Group differences in serum ferritin (Ft), soluble transferrin receptor (sTfR), total body iron (TBI), hemoglobin (Hb), hematocrit (Hct), iron depletion prevalence (Ft <15 μg/L), peak oxygen consumption (VO_2peak), exercise minutes per week, and diet logs were assessed.

RESULTS

The prevalence of iron depletion was greater in OvEU when compared to AMEN (26% vs. 15%, p = 0.04). No significant differences were observed between AMEN and OvEU in Ft (30.2 ± 2.2 vs. 24.9 ± 2.6 μg/L; p = 0.62), sTfR (5.2 ± 1.4 vs. 4.9 ± 1.5 mg/L; p = 0.95), TBI (5.3 ± 2.7 vs. 4.8 ± 3.7 mg/kg; p = 0.42), Hb (13.2 ± 0.4 vs. 13.4 ± 0.6 g/dL; p = 0.80), Hct (39.5 ± 0.8% vs. 39.8 ± 4.1%; p = 0.93), or exercise parameters. AMEN consumed more vitamin C than OvEU (269 ± 180 vs. 129 ± 141 mg/day, p < 0.001), but all other dietary factors were similar between AMEN and OvEU.

CONCLUSION

Exercising women with ovulatory, eumenorrheic cycles are at a greater risk of iron depletion than exercising, amenorrheic women. Thus, menstrual function must be considered when screening for poor iron status in exercising women.

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.

Low RMRratio as a Surrogate Marker for Energy Deficiency, the Choice of Predictive Equation Vital for Correctly Identifying Male and Female Ballet Dancers at Risk

Ballet dancers are reported to have an increased risk for energy deficiency with or without disordered eating behavior. A low ratio between measured (m) and predicted (p) resting metabolic rate (RMRratio < 0.90) is a recognized surrogate marker for energy deficiency. We aimed to evaluate the prevalence of suppressed RMR using different methods to calculate pRMR and to explore associations with additional markers of energy deficiency. Female (n = 20) and male (n = 20) professional ballet dancers, 19–35 years of age, were enrolled. mRMR was assessed by respiratory calorimetry (ventilated open hood). pRMR was determined using the Cunningham and Harris–Benedict equations, and different tissue compartments derived from whole-body dual-energy X-ray absorptiometry assessment. The protocol further included assessment of body composition and bone mineral density, blood pressure, disordered eating (Eating Disorder Inventory-3), and for females, the Low Energy Availability in Females Questionnaire. The prevalence of suppressed RMR was generally high but also clearly dependent on the method used to calculate pRMR, ranging from 25% to 80% in males and 35% to 100% in females. Five percent had low bone mineral density, whereas 10% had disordered eating and 25% had hypotension. Forty percent of females had elevated Low Energy Availability in Females Questionnaire score and 50% were underweight. Suppressed RMR was associated with elevated Low Energy Availability in Females Questionnaire score in females and with higher training volume in males. In conclusion, professional ballet dancers are at risk for energy deficiency. The number of identified dancers at risk varies greatly depending on the method used to predict RMR when using RMRratio as a marker for energy deficiency.

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.

Comparison of nutritional intake, body composition, bone mineral density, and isokinetic strength in collegiate female dancers

This study compared nutritional intake, body composition, bone mineral density, and isokinetic strength by dance type in collegiate female dancers. The study subjects included Korean dancers (n=12), ballet dancers (n=13), contemporary dancers (n=8), and controls (n=12). Nutritional intake was estimated using the Computer Aided Nutritional Analysis Program. Body composition and bone mineral density were measured using dual-energy X-ray absorptiometry. Isokinetic knee joint strength was measured by Cybex 770-NORM. All statistical analyses were performed by SAS 9.2. Means and standard deviations were calculated using descriptive statistics. One-way analysis of variance was applied to evaluate nutritional intake, body composition, bone mineral density, and isokinetic strength differences. Duncan multiple range test was used for post hoc testing. A level of significance was set at P<0.05. The study results indicated no significant differences in nutritional in-take among dancer types. Despite no significant differences in body composition among dancer types, contemporary and ballet dancers had lower body fat percentages than controls (P<0.05). No significant differences were seen in bone mineral density and bone mineral contents among dancer types. No significant differences were found in isokinetic strength in right or left knee flexion and extension at 60°/sec (P<0.05). There were significant differences in body composition and isokinetic strength between dancer groups and the control group. Further studies of different professional dance type and more scientific methods of dance training are needed.