Role of energy balance in athletic menstrual dysfunction

Sport Specialization and Low Bone Mineral Density in Female High School Distance Runners

CONTEXT

Sport specialization may contribute to sport injury and menstrual dysfunction in female high school distance runners. Despite the recent growth in sport specialization, including among high school-aged runners, the association of sport specialization with bone mineral density (BMD) remains poorly described.

OBJECTIVE

To evaluate whether sport specialization was associated with BMD in female high school distance runners.

DESIGN

Cross-sectional study.

SETTING

Six high schools.

PATIENTS OR OTHER PARTICIPANTS

Sixty-four female runners (age = 15.6 ± 1.4 years) who competed in cross-country or track distance events and were not currently on birth control medication.

MAIN OUTCOME MEASURE(S)

Each runner completed a survey on menstrual history and sport participation. Height and weight were measured, and dual-energy x-ray absorptiometry was used to measure whole-body, spine, and hip BMD. Each runner was assigned a sport specialization status: low (participation in ≥1 nonrunning sport and distance-running sport(s) for ≤8 mo/y); moderate (participation in both distance-running sport(s) ≥9 mo/y and ≥1 nonrunning sport(s) or limited to distance-running sport(s) for ≤8 mo/y); or high (participation only in distance-running sport(s) for ≥9 mo/y). Multivariable logistic regression was performed to determine the adjusted odds ratio and 95% confidence interval for sport specialization to BMD values, adjusting for body mass index and gynecological age.

RESULTS

Overall, 21.9%, 37.5%, and 40.6% of participants were high, moderate, or low sport specializers, respectively. Low BMD (spine or whole-body BMD z score < -1.0 [standardized by age and sex normative values]) was present in 23 (35.9%) runners. Compared with low sport specializers, high sport specializers were 5 times more likely (adjusted odds ratio = 5.42, 95% confidence interval = 1.3, 23.3; P = .02) to have low BMD.

CONCLUSIONS

A high level of sport specialization in high school female distance runners may be associated with a heightened risk for low BMD. Further investigation of this association is warranted due to the health concerns about low BMD in adolescent female runners.

Biomarkers Correlate With Body Composition and Performance Changes Throughout the Season in Women's Division I Collegiate Soccer Players

The purpose of this study was to evaluate the effects of a competitive soccer season on biomarkers and performance metrics in order to determine the correlation between changes in biomarkers, body composition, and performance outcomes. Twenty-one Division 1 female collegiate soccer players were monitored throughout the 16-week season. Player workload was measured using heart rate and Global Position Satellite systems at all practices and games. Performance testing, including vertical jump, VO_2max, and 3-repetition maximum testing for bench press, squat and deadlift, occurred prior to pre-season and immediately post-season. Blood draws occurred prior to preseason and every 4-weeks thereafter, following a game. Body composition was assessed prior to the start of season (week 0) and weeks 6, 10, 14, and 17 (post-season). Delta area under the curve was calculated for biomarkers and body composition variables to account for seasonal changes adjusted for baseline. Pearson-product moment correlations were used to assess relationships with significance set at p < 0.05. Trends were considered p ≤ 0.10. No significant time main effects were seen for anabolic biomarkers (p > 0.05). Significant time effects were seen for catabolic biomarkers throughout the season (p = 0.001). No changes in body weight, VO_2max, vertical jump, and deadlift occurred. Squat and bench press improved (p = 0.01 and p = 0.02, respectively) with a decline in percent body fat (p = 0.03) and a trend for increased fat free mass (p = 0.09). Additionally, total cortisol (TCORT) negatively correlated with fat free mass (r = −0.48; p = 0.03) and positively correlated with VO_2max (r = 0.47; p = 0.04). A trend was shown for a positive correlation between both TCORT and free cortisol (FCORT) and percent body fat (r = 0.39; r = 0.40; p = 0.08, respectively). IGF-1 and growth hormone positively correlated to deadlift (r = 0.57; P = 0.02 and r = 0.59; p = 0.03), whereas creatine kinase showed a trend for a positive correlation with deadlift (r = 0.49; p = 0.06). IL-6 negatively correlated with bench press (r = −0.53; p = 0.03). These findings support a relationship between biomarkers, performance outcomes, and body composition. Biomarker monitoring may be useful to detect individual player's physiological response to an athletic season and may help provide insights in efforts to optimize performance outcomes.

A Nutrition Screening Form for Female Infertility Patients

A Nutrition Screening Form (NSF) was designed to identify lifestyle risk factors that negatively impact fertility and to provide a descriptive profile of 300 female infertility patients in a private urban infertility clinic. The NSF was mailed to all new patients prior to the initial physician's visit and self-reported data were assessed using specific criteria to determine if a nutrition referral was warranted. This observational study revealed that 43% of the women had a body mass index (BMI) <20 or ≥25 kg/m2, known risks for infertility. Almost half reported a history of “dieting” and unrealistic weight goals potentially limiting energy and essential nutrients. A high number reported eating disorders, vegetarianism, low fat or low cholesterol diets, and dietary supplement use. Fourteen percent appeared not to supplement with folic acid, 13% rated exercise as “extremely” or “very active”, and 28% reported a “high” perceived level of stress. This preliminary research demonstrated that a NSF can be a useful tool to identify nutrition-related lifestyle factors that may negatively impact fertility and identified weight, BMI, diet, exercise, and stress as modifiable risk factors deserving future research. NSF information can help increase awareness among health professionals and patients about the important link between nutrition, fertility, and successful reproductive outcomes.

National athletic trainers' association position statement: preventing, detecting, and managing disordered eating in athletes

OBJECTIVE

To present recommendations for the prevention, detection, and comprehensive management of disordered eating (DE) in athletes.

BACKGROUND

Athletes with DE rarely self-report their symptoms. They tend to deny the condition and are often resistant to referral and treatment. Thus, screenings and interventions must be handled skillfully by knowledgeable professionals to obtain desired outcomes. Certified athletic trainers have the capacity and responsibility to play active roles as integral members of the health care team. Their frequent daily interactions with athletes help to facilitate the level of medical surveillance necessary for early detection, timely referrals, treatment follow-through, and compliance.

RECOMMENDATIONS

These recommendations are intended to provide certified athletic trainers and others participating in the health maintenance and performance enhancement of athletes with specific knowledge and problem-solving skills to better prevent, detect, and manage DE. The individual biological, psychological, sociocultural, and familial factors for each athlete with DE result in widely different responses to intervention strategies, challenging the best that athletics programs have to offer in terms of resources and expertise. The complexity, time intensiveness, and expense of managing DE necessitate an interdisciplinary approach representing medicine, nutrition, mental health, athletic training, and athletics administration in order to facilitate early detection and treatment, make it easier for symptomatic athletes to ask for help, enhance the potential for full recovery, and satisfy medicolegal requirements. Of equal importance is establishing educational initiatives for preventing DE.

The female football player, disordered eating, menstrual function and bone health

Most female football players are healthy. However, recent findings from our studies on Norwegian female elite athletes also show that football players are dieting and experiencing eating disorders, menstrual dysfunction and stress fractures. Dieting behaviour and lack of knowledge of the energy needs of the athlete often leads to energy deficit, menstrual dysfunction and increased risk of bone mass loss. Although dieting, eating disorders and menstrual dysfunction are less common than in many other sports, it is important to be aware of the problem as eating disorders in female athletes can easily be missed. Therefore, individuals, including the players themselves, coaches, administrators and family members, who are involved in competitive football, should be educated about the three interrelated components of the female athlete triad (disordered eating, menstrual dysfunction and low bone mass), and strategies should be developed to prevent, recognise and treat the triad components.

Energy balance in weight stable athletes with and without menstrual disorders

The energy balance and nutritional adequacy was assessed in a group of runners with irregular menstrual function (IR, n = 10) and in a comparable group of runners with normal menstrual function (R, n = 10). Based on computerized records of 3 days food intake, the mean content of energy and macronutrients were estimated. Excess energy expenditure (EEE) during training hours was estimated using HF monitoring and individual HF/VO2 nomograms. For the rest of a daily 24 h cycle, estimated values for basal metabolic rate (BMR) and sedentary metabolic rate were applied. Daily training-related excess energy expenditure (2.1 +/- 0.3 vs 2.2 +/- 0.4) MJ (Mean +/- SEM) and total energy expenditure (TEE) (11.0 +/- 0.3 vs 11.2 +/- 0.4) MJ in R vs IR were not different in the two groups. Calculated daily energy intake (EI) was, however, significantly lower in IR (9.7 +/- 0.5 MJ) than in R (12.3 +/- 0.7 MJ), (P = 0.007). Calculated EI and TEE were in balance in R athletes. When the same calculations were applied on IR athletes, a moderate but statistically significant negative energy balance was found (-1.5 +/- 0.6 MJ, P = 0.03). The calculated energy deficit was supported by significantly lower levels of free thyroxine in IR athletes, and may indicate an adaptive lower BMR in IR athletes. Mean intakes of carbohydrates (7.0 g/kg in R and 5.7 g/kg in IR) and protein (1.71 g/kg in R and 1.49 g/kg in IR) were close to guidelines. Intakes were not significantly different in the two groups. The most important difference in macronutrient intake was found in dietary fat (1.70 g/kg in R and 1.04 g/kg in IR) that was significantly lower in the IR group than in the R group (P = 0.007). The weight stable IR and R athletes seemed to meet the recommended intake of carbohydrates, protein and fat in their diet fairly well. However, according to the present calculations, a small energy deficit was observed in IR athletes but not in R athletes. Compared with the intake of the R athletes, this energy deficit seems primarily to be related to a lower intake of dietary fat in IR athletes.

Nutritional aspects of women strength athletes

Strength training elicits sports related and health benefits for both men and women. Although sexual dimorphism is observed in exercise metabolism, there is little information outlining the specific nutritional needs of women strength athletes. Many women athletes restrict energy intake, specifically fat consumption, in order to modify body composition, but this nutritional practice is often counter-productive. Compared to men, women appear to be less reliant on glycogen during exercise and less responsive to carbohydrate mediated glycogen synthesis during recovery. Female strength athletes may require more protein than their sedentary and endurance training counterparts to attain positive nitrogen balance and promote protein synthesis. Therefore, women strength athletes should put less emphasis on a very high carbohydrate intake and more emphasis on quality protein and fat consumption in the context of energy balance to enhance adaptations to training and improve general health. Attention to timing of nutrient ingestion, macronutrient quality, and dietary supplementation (for example, creatine) are briefly discussed as important components of a nutritionally adequate and effective strength training diet for women.

Energy Balance and Reproductive Function in Active Women

Athletes engaged in rigorous training programs expend large amounts of energy and require appropriate energetic compensation to maintain or improve performance. If these exercise regimens are not fueled sufficiently, a negative energy balance will likely emerge and lead to a broad spectrum of menstrual cycle disturbances and less than optimal performance. This review examines the theory and evidence surrounding energy availability and reproductive function. Implications for performance and treatment strategies are also addressed. Key words: energy intake, energy expenditure, energy availability, menstrual disorders, LH pulsatility, amenorrhea

The female athlete triad: an emerging role for physical therapy

Over the last thirty years, participation by girls and women in organized athletics has increased dramatically. This presents unique challenges in the area of sports medicine, orthopaedics, and pediatrics. While the benefits of participation in sports and exercise vastly outweigh the risks of permanent injury, an evolving concern is the number of stress fractures in active women. The female athlete triad ("triad") describes the coexistence of 3 distinct medical conditions that may occur in athletic girls and women. Originally, the triad included eating disorders, amenorrhea, and osteoporosis. Presently, it includes eating disorders/disordered eating behavior, amenorrhea/oligomenorrhea, and decreased bone mineral density (osteoporosis and osteopenia). Briefly, when coupled with inadequate nutrition, the high caloric expenditure of exercise training resultsin a sustained negative caloric balance or low energy availability, which is exquisitely sensed by the hypothalamus, initiating a complex neuroendocrine adaptive cascade. This cascade is associated with changes in the hypothalamic-pituitary-ovarian axis, such that estrogen levels are decreased, resulting in reproductive dysfunction that may include amenorrhea, oligomenorrhea, or anovulation. Low estrogen in otherwise young healthy women, like menopause, is associated with decreased bone mineral density and increased risk of fractures. The triad is not an inevitable consequence of participation in sports or physical activity at any level, however, exercise may contribute to the disruption of caloric balance. The triad is a complex disorder that requires intervention by a multidisciplinary team. Physical therapists bring a unique expertise to the team. The present review summarizes each component of the triad, component linkage, and the role of physical therapy in prevention, assessment, and intervention.

Dietary recommendations and athletic menstrual dysfunction

Exercise-induced or athletic menstrual dysfunction (amenorrhoea, oligomenorrhoea, anovulation, luteal phase deficiency, delayed menarche) is more common in active women and can significantly affect health and sport performance. Although athletic amenorrhoea represents the most extreme form of menstrual dysfunction, other forms can also result in suppressed estrogen levels and affect bone health and fertility. A number of factors, such as energy balance, exercise intensity and training practices, bodyweight and composition, disordered eating behaviours, and physical and emotional stress levels, may contribute to the development of athletic menstrual dysfunction. There also appears to be a high degree of individual variation with respect to the susceptibility of the reproductive axis to exercise and diet-related stresses. The dietary issues of the female athlete with athletic menstrual dysfunction are similar to those of her eumenorrhoeic counterpart. The most common nutrition issues in active women are poor energy intake and/or poor food selection, which can lead to poor intakes of protein, carbohydrate and essential fatty acids. The most common micronutrients to be low are the bone-building nutrients, especially calcium, the B vitamins, iron and zinc. If energy drain is the primary contributing factor to athletic menstrual dysfunction, improved energy balance will improve overall nutritional status and may reverse the menstrual dysfunction, thus returning the athlete to normal reproductive function. Because bone health can be compromised in female athletes with menstrual dysfunction, intakes of bone-building nutrients are especially important. Iron and zinc are typically low in the diets of female athletes if meat products are avoided. Adequate intake of the B vitamins is also important to ensure adequate energy production and the building and repair of muscle tissue. This review briefly discusses the various factors that may affect athletic menstrual dysfunction and two of the proposed mechanisms: the energy-drain and exercise-intensity hypotheses. Because energy drain can be a primary contributor to athletic menstrual dysfunction, recommendations for energy and the macro- and micronutrients are reviewed. Methods for helping the female athlete to reverse athletic menstrual dysfunction are discussed. The health consequences of trying to restrict energy intake too dramatically while training are also reviewed, as is the importance of screening athletes for disordered eating. Vitamins and minerals of greatest concern for the female athlete are addressed and recommendations for intake are given.

A high exercise load is linked to pathological weight control behavior and eating disorders in female fitness instructors

Demographic data, exercise habits, weight control behavior, attitudes towards body shape, eating disorder (ED) experience, and menstrual regularity among female fitness instructors were descriptively assessed. A 60-item questionnaire was sent to 295 female fitness instructors at eight fitness centers. Responders (57%) reported a mean weekly exercise load of 5.5 h week(-1) (SD 2.6), which indicates frequent training, however, less than that of athletes. Overall, 35% reported ED experience (DSM-IV criteria), with an onset at 15-17 years of age. The problems had lasted 5-7 years, and 20% of the entire group reported recovery, however, 11% still had EDs. For the entire group, it was found that a high weekly exercise load was linked to a pathological weight control behavior. Fitness instructors with an active ED exercised more than instructors who never had an ED or who had a past ED. Menstrual irregularity was more common among instructors who did not use contraceptives (14%), compared to those who did (5%). As ED experience and pathological weight control behavior were common in the studied group, the importance of guidelines regarding communication from female fitness instructors about healthy training habits to regular exercisers is discussed in the article.

Female athlete triad

OBJECTIVE

To describe the components of female athlete triad, the proposed mechanisms that may relate to its causation, and some screening and treatment options that may be used by the clinician who encounters this clinical entity in patients.

DATA SOURCES

A qualitative review of the literature was performed.

RESULTS

This article provides the clinician with current information relevant to understanding and recognizing female athlete triad in at-risk patients. The components of the triad-amenorrhea, disordered eating, and osteoporosis-are interrelated in multifactorial etiology, pathogenesis, and consequences. Proposed causal factors include inadequate nutrition, menstrual status, training intensity and frequency, body size and composition, and psychological and physiological stress. There should be a high index of suspicion in all females athletes for the presence of and/or increased risk for female athlete triad. An increased awareness of the existence of the problem and its presenting signs and symptoms is the key to screening for this syndrome. The most efficacious treatment lies in its prevention.

CONCLUSIONS

Female athlete triad is an interrelated, multifactorial syndrome comprised of disordered eating, amenorrhea, and osteoporosis. It is a common entity among female athletes. Prevention, early detection, and early treatment are absolutely essential to maintain the athletes health into maturity and to prevent the serious consequences of this triad. The long-term effects of some triad components are still unknown.

Dietary intakes of elite female athletes in Greece

BACKGROUND

Although there is a great interest in sports in Greece, there are very few data regarding dietary intakes and habits of Greek elite female athletes. The present study assesses the dietary intakes and the energy balance of elite female athletes of four different sports (volleyball, middle distance running, ballet dancing, and swimming) and a non-athletic control group.

METHODS

Data were collected over two seasons, the training and the competitive, using 7-day weighed dietary records. Energy expenditure was calculated from 7-day activity records. Anthropometric measurements were also taken for all athletes.

RESULTS

Athletes and controls had similar BMI values. Per cent body fat was lower for athletes compared with controls. Between sports, middle distance runners had the lowest per cent body fat. No significant differences were found between mean energy intake of athletes and controls. Mean energy intake was found lower than calculated energy expenditure, for all four teams. Macronutrient and micronutrient intakes of the athletes were not statistically different from those of the non-athletic control group. Mean micronutrient intakes were found above the recommended values with the exception of iron. Both athletes and controls had a high intake of vitamin C that is a characteristic of the population of the Mediterranean countries.

CONCLUSIONS

Energy intakes varied between sports and between athletes of the same sport. Calculated energy expenditure was higher from the reported energy intake for most athletes. Athletes with the lowest energy intakes reported menstrual abnormalities.

Joint Position Statement: nutrition and athletic performance. American College of Sports Medicine, American Dietetic Association, and Dietitians of Canada

It is the position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine that physical activity, athletic performance, and recovery from exercise are enhanced by optimal nutrition. These organizations recommend appropriate selection of food and fluids, timing of intake, and supplement choices for optimal health and exercise performance. This position paper reviews the current scientific data related to the energy needs of athletes, assessment of body composition, strategies for weight change, the nutrient and fluid needs of athletes, special nutrient needs during training, the use of supplements and nutritional ergogenic aids, and the nutrition recommendations for vegetarian athletes. During times of high physical activity, energy and macronutrient needs-especially carbohydrate and protein intake-must be met in order to maintain body weight, replenish glycogen stores, and provide adequate protein for building and repair of tissue. Fat intake should be adequate to provide the essential fatty acids and fat-soluble vitamins, as well as to help provide adequate energy for weight maintenance. Overall, diets should provide moderate amounts of energy from fat (20% to 25% of energy); however, there appears to be no health or performance benefit to consuming a diet containing less than 15% of energy from fat. Body weight and composition can affect exercise performance, but should not be used as the sole criterion for sports performance; daily weigh-ins are discouraged. Consuming adequate food and fluid before, during, and after exercise can help maintain blood glucose during exercise, maximize exercise performance, and improve recovery time. Athletes should be well-hydrated before beginning to exercise; athletes should also drink enough fluid during and after exercise to balance fluid losses. Consumption of sport drinks containing carbohydrates and electrolytes during exercise will provide fuel for the muscles, help maintain blood glucose and the thirst mechanism, and decrease the risk of dehydration or hyponatremia. Athletes will not need vitamin and mineral supplements if adequate energy to maintain body weight is consumed from a variety of foods. However, supplements may be required by athletes who restrict energy intake, use severe weight-loss practices, eliminate one or more food groups from their diet, or consume high-carbohydrate diets with low micronutrient density. Nutritional ergogenic aids should be used with caution, and only after careful evaluation of the product for safety, efficacy, potency, and whether or not it is a banned or illegal substance. Nutrition advice, by a qualified nutrition expert, should only be provided after carefully reviewing the athlete's health, diet, supplement and drug use, and energy requirements.

Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance

It is the position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine that physical activity, athletic performance, and recovery from exercise are enhanced by optimal nutrition. These organizations recommend appropriate selection of food and fluids, timing of intake, and supplement choices for optimal health and exercise performance. This position paper reviews the current scientific data related to the energy needs of athletes, assessment of body composition, strategies for weight change, the nutrient and fluid needs of athletes, special nutrient needs during training, the use of supplements and nutritional ergogenic aids, and the nutrition recommendations for vegetarian athletes. During times of high physical activity, energy and macronutrient needs--especially carbohydrate and protein intake--must be met in order to maintain body weight, replenish glycogen stores, and provide adequate protein for building and repair of tissue. Fat intake should be adequate to provide the essential fatty acids and fat-soluble vitamins, as well as to help provide adequate energy for weight maintenance. Overall, diets should provide moderate amounts of energy from fat (20% to 25% of energy); however, there appears to be no health or performance benefit to consuming a diet containing less than 15% of energy from fat. Body weight and composition can affect exercise performance, but should not be used as the sole criterion for sports performance; daily weigh-ins are discouraged. Consuming adequate food and fluid before, during, and after exercise can help maintain blood glucose during exercise, maximize exercise performance, and improve recovery time. Athletes should be well-hydrated before beginning to exercise; athletes should also drink enough fluid during and after exercise to balance fluid losses. Consumption of sport drinks containing carbohydrates and electrolytes during exercise will provide fuel for the muscles, help maintain blood glucose and the thirst mechanism, and decrease the risk of dehydration or hyponatremia. Athletes will not need vitamin and mineral supplements if adequate energy to maintain body weight is consumed from a variety of foods. However, supplements may be required by athletes who restrict energy intake, use severe weight-loss practices, eliminate one or more food groups from their diet, or consume high-carbohydrate diets with low micronutrient density. Nutritional ergogenic aids should be used with caution, and only after careful evaluation of the product for safety, efficacy, potency, and whether or not it is a banned or illegal substance. Nutrition advice, by a qualified nutrition expert, should only be provided after carefully reviewing the athlete's health, diet, supplement and drug use, and energy requirements.

Nutritional needs of the female athlete

US women, including female athletes, are under ever increasing pressure to be thin ar thinner. this pressure to achieve and maintain a low body weight leads to potentially harmful patterns of long-term dieting or disordered eating, which can affect long-term health. Some of the health consequences of long-term energy restriction in female athletes may include poor energy and nutrient intakes, poor nutritional status, decreased RMR and total daily energy expenditure, increased psychological stress and risk for a clinical eating disorder, and increased risk for exercise-induced amenorrhea and osteoporosis. Female athletes participating in thin-build sports may be at risk for the disorders of the female athlete triad: disordered eating, amenorrhea, and osteoporosis. This triad of disorders can also produce severe health consequences that can influence present and future health. Strategies for helping active women get off the dieting "bandwagon" requires the identification of an appropriate and healthy body weight, good eating and exercise habits, and techniques for maintaining these habits throughout life.

Psychosocial factors associated with dieting behaviors among female adolescents

This study determined whether female adolescents who were attempting weight loss (dieters) differ from those who were not (nondieters) with respect to a set of psychosocial factors. The sample consisted of 2,536 normal-weight and underweight female adolescents who participated in the National Longitudinal Adolescent Health Survey. Psychosocial factors examined included depression (four measures), self-esteem, trouble in school, school connectedness, family connectedness, sense of community (two measures), grades, autonomy, and protective factors. MANCOVA revealed significant differences between dieters and nondieters. Self-esteem was the strongest contributing factor differentiating dieters and nondieters. These results have implications for health education and health promotion with regard to both primary and secondary prevention. Self-esteem building should be incorporated within the parameters of a comprehensive school health program and certainly should be a component in any nutrition education program aimed at preventing unhealthy dieting behaviors. By understanding the factors associated with these behaviors, it may be easier to identify individuals attempting weight loss despite being of normal or low body weight.

Sex steroid metabolism and menstrual irregularities in the exercising female. A review

This article aims to clarify why, and by which mechanisms, exercise may influence the normal menstrual cycle. Therefore, the vast amount of literature on this subject is reviewed and a critical appraisal of the most widespread hypotheses if offered. The strikingly low body mass which frequently accompanies exercise-related menstrual irregularities (ERMI) has led some authors to develop a hypothesis which postulates that a critical percentage of body fat is essential to trigger normal menstruation. The relevance of any reference to anorexia nervosa to support this view lacks consistency: female athletes differ in many ways from patients with anorexia nervosa, not least in their excellent physical status which is essential to deliver first-class performances. ERMI is not identical to the so-called female athlete triad, a complicated pathology that involves ERMI, premature osteoporosis and disordered eating. ERMI itself does not seem to have any substantial pathological effects as long as attention is paid to preventing osteoporosis or stress fractures which may result from prolonged hypo-estrogenaemia. In the female athlete with ERMI who wishes to conceive, the accompanying subfertility may necessitate a response other than a prompt reduction in training intensity, as this is hardly a first choice for any top athlete. During recent years, a number of prospective studies have greatly contributed to our understanding of the complexity of the mechanisms involved in ERMI. Older hypotheses, such as those considering hyperprolactinaemia as the cornerstone of ERMI, have now been firmly rejected. The present hypotheses emphasise the importance of caloric deficiency and limited energy availability, although they still fail to identify the actual mechanism that causes ERMI. There is, however, evidence that ERMI is produced by a disturbance of the hypothalamic gonadotrophin-releasing hormone oscillator. This disturbance is caused by either an insufficient estrogen or progesterone feedback or by an imbalance of local opioid peptide and catecholamine activities mediated by gamma-aminobutyric acid (GABA), corticotrophin-releasing hormone and insulin-like growth factor-1. More recent experiments have also linked ERMI with changes in steroid metabolism, in particular, an increasing activity of catecholestrogens possibly leading to enhanced intracerebral noradrenaline (norepinephrine) levels that may interfere with normal gonadotrophin release. This article demonstrates that the outcome of the many studies of ERMI is characterised by much controversy and numerous methodological flaws. The importance and complexity of some recent findings necessitate a comprehensive study which links older and newer findings within a critical perspective.

Nutritional status of female athletes with subclinical eating disorders

OBJECTIVE

To assess the energy and nutritional status of female athletes with subclinical eating disorders and compare them with that of control subjects and standard norms.

DESIGN

Group classification (subclinical eating disorder or control) was based on responses to a health and diet history questionnaire, a battery of self-report eating disorder questionnaires, and an in-depth interview. Energy and nutrient intakes and energy expenditure were determined by means of 7-day weighed food records and 7-day activity logs. Micronutrient status was assessed for iron, zinc, magnesium, vitamin B-12, and folate.

SUBJECTS

Twenty-four female athletes with subclinical eating disorders and 24 female control athletes.

STATISTICAL ANALYSES

Descriptive statistics were used to analyze demographic data. One-way analysis of variance was used to determine group differences in energy and nutrient intakes, energy balance, and blood values.

RESULTS

Groups were similar in age, height, weight, fat-free mass, and body mass index. Mean energy intake was lower in the group with subclinical eating disorders (1,989 kcal/day) than in the control group (2,300 kcal/day; P=.004), whereas mean energy expenditures were similar (2,405 and 2,293 kcal/day, respectively). The group with subclinical eating disorders had significantly (P<.05) lower mean protein and fat intakes compared with the control group; mean micronutrient intakes were not significantly different. Mean status measures for iron, zinc, magnesium, vitamin B-12, and folate were within the normal ranges for both groups and no differences were noted between the groups. A similar number of athletes within each group used vitamin/mineral supplements < or = 4 times per week.

CONCLUSION

Although female athletes with subclinical eating disorders had dietary intakes of energy, protein, carbohydrate, and certain micronutrients that were below recommended levels, micronutrient status appeared relatively unaffected, probably due to their use of supplements.

American College of Sports Medicine position stand. The Female Athlete Triad

The Female Athlete Triad is a syndrome occurring in physically active girls and women. Its interrelated components are disordered eating, amenorrhea, and osteoporosis. Pressure placed on young women to achieve or maintain unrealistically low body weight underlies development of the Triad. Adolescents and women training in sports in which low body weight is emphasized for athletic activity or appearance are at greatest risk. Girls and women with one component of the Triad should be screened for the others. Alone or in combination, Female Athlete Triad disorders can decrease physical performance and cause morbidity and mortality. More research is needed on its causes, prevalence, treatment, and consequences. All individuals working with physically active girls and women should be educated about the Female Athlete Triad and develop plans to prevent, recognize, treat, and reduce its risks.

Chronic dieting in active women: what are the health consequences?

Evidence suggests that there is ever increasing pressure on American women to be thin. This pressure drives women to want to be thinner than what might be realistically achieved or required for good health. Our goal as nutrition and health professionals is to help women achieve and maintain a healthy body weight throughout the life-cycle. This includes helping young females accept their body size and shape as well and placing more emphasis on health and fitness than on weight in this population. This process begins with the identification of what constitutes a healthy body weight for a particular individual based on genetic, physiological, social, and psychological factors. In addition, it should be a weight that can be realistically maintained while keeping risk factors for chronic disease low. Table 1 outlines some strategies for helping individuals to identify and maintain a healthy body weight.