Low Energy Availability in Exercising Women: Historical Perspectives and Future Directions

Assessment of Relative Energy Deficiency in Sport (REDs) Risk among Adolescent Acrobatic Gymnasts

Energy imbalance exposes athletes to relative energy deficiency in sports (REDs) syndrome. Data on energy consumption, REDs, and bone mineral density (BMD) in adolescent acrobatic gymnasts, especially in males, are scarce. Our aim was to examine the eating habits, energy balance, body composition, and BMD of these athletes. In this study, 18 healthy adolescents participating in competitive acrobatic gymnastics completed a questionnaire, underwent a dual-energy X-ray absorptiometry scan (DXA), received a food log, and had their activities monitored for 3 days. Eighteen acrobats were enrolled (mean age: 14.3 ± 1.2 years; males: 6/18). The mean total body BMD Z-score was 0.4 ± 1.0. Top-position acrobats (7/18) had significantly lower total body BMD Z-scores than base-positioned acrobats (-0.2 ± 0.3 vs. 0.8 ± 0.3, p = 0.032), though their forearms were not significantly different (0.2 ± 0.5 vs. 0.8 ± 0.7, p = 0.331). No sex differences were found for BMD Z-scores, BMI, or energy availability. The BMD parameters of the acrobats were within the normal range for a healthy pediatric population, although three had low BMDs (<-1 SD) for healthy athletes. Total body and LS BMD Z-scores were significantly lower in top-position athletes compared to base-position athletes. These findings suggest personalized (top vs. base) training programs (high-impact training) that may achieve better health outcomes.

Hungry runners - low energy availability in male endurance athletes and its impact on performance and testosterone: mini-review

Low Energy Availability (LEA) arises from the inability to cover energy needs and requirements of training or normal physiological functions. This value differs from the energy balance, which takes into account the total daily energy intake compared to all the energy expended, regardless of the amount of fat-free mass. Insufficient energy consumption affects recovery, adaptation processes, increases the risk of injury or illness, so all of this can negatively affect performance. This mini-review is written on research articles in Pubmed database related to LEA in endurance-trained men and its impact on performance and testosterone. This article also clarifies the prevalence of LEA in male endurance athletes and its correlation to Relative Energy Deficiency in Sports (RED-S). LEA occurs in male endurance athletes and correlates with decreased testosterone levels, decreased bone density and also Resting Metabolic Rate. In endurance-trained men, there is great potential for the negative consequences of low energy availability. It can also be said that there are possibilities for primary screening, so we recommend regular check-ups of blood markers, body structure and keeping not only training but also dietary records, which can increase awareness of an adequate energy balance.

Dietary Intake over a 7-Day Training and Game Period in Female Varsity Rugby Union Players

This study estimated the daily energy intake (EI) and energy expenditure (TDEE) in female varsity rugby union players during a weekly training/game cycle. Fifteen (nine forwards, six backs) players (20.5 ± 0.4 y, 167.1 ± 1.8 cm, 74.9 ± 2.9 kg) were monitored for a 7-day period (one fitness, two heavy training, one light training, one game, and two recovery days) during their regular season. The average EI throughout the week for all 15 players was 2158 ± 87 kcal. There were no significant differences between days, but the lowest EI (1921 ± 227 kcal) occurred on the mid-week recovery day and the highest on game day (2336 ± 231 kcal). The average TDEE was 2286 ± 168 kcal (~6% > EI). The mean energy availability (EA) over the 7-day period was 31.1 ± 3.6 kcal/kg FFM/day for the group. Of the players, 14% were in the optimal EA range (>45 kcal/kg FFM/day); 34% were in the moderate range (≥30−45 kcal/kg FFM/day); and 52% had a poor EA of <30 kcal/kg FFM/day. Carbohydrate (3.38 ± 0.36 g/kg/day, 45% of EI); fat (1.27 ± 0.12 g/kg/day, 37% of EI); and protein (1.38 ± 0.12 g/kg/day, 18% of EI) consumption remained similar throughout the week (p > 0.05). The players consumed 6% less energy than they expended, providing poor to moderate EA; therefore, daily carbohydrate intake recommendations were not met.

Investigating the prevalence of low energy availability, disordered eating and eating disorders in competitive and recreational female endurance runners

Eating disorders (ED), disordered eating (DE) and low energy availability (LEA) can be detrimental to health and performance. Previous studies have independently investigated prevalence of ED, DE or LEA, however limited studies have combined methods identifying risk within female runners. The aim of this study was to identify prevalence of ED, DE and LEA in United Kingdom-based female runners and associations between age, competition level and running distance. 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 n = 524 responses eligible for analysis were received. A total of n = 248 (47.3%), n = 209 (40%) and n = 49 (9.4%) athletes were at risk of LEA, DE and ED, respectively. LEAF-Q scores differed based upon age (Age: H₍₃₎ =  23.998, p≤0.05) and competitive level (Comp: H₍₁₎ =  7.682, p≤0.05) whereas FAST scores differed based on age (Age: F_(3,523) =  4.753, p≤0.05). Tukey's post-hoc tests showed significantly higher FAST scores in 18-24 years compared to all other age categories (p≤0.05). Stepwise multiple regression demonstrated age and competitive level modestly predicted LEAF-Q scores (R²_adj = 0.047, F(2,523)  =  13.993, p≤0.05, VIF = 1.0) whereas age modestly predicted FAST scores (R²_adj = 0.022, F(_1,523)  =  12.711, p≤0.05, VIF = 1.0). These findings suggest early identification, suitable screening methods and educational intervention programmes should be aimed at all levels of female endurance runners.

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.

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

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

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.

Prevalence of impaired physiological function consistent with Relative Energy Deficiency in Sport (RED-S): an Australian elite and pre-elite cohort

OBJECTIVES

Athlete health, training continuity and performance can be impeded as a result of Relative Energy Deficiency in Sport (RED-S). Here we report the point prevalence of symptoms described by the RED-S model in a mixed-sport cohort of Australian female athletes.

METHODS

Elite and pre-elite female athletes (n=112) from eight sports completed validated questionnaires and underwent clinical assessment to assess the point prevalence of RED-S symptoms. Questionnaires included the Depression, Anxiety and Stress Questionnaire (DASS-21), Generalized Anxiety Disorder (GAD-7), Center for Epidemiological Studies Depression Scale (CES-D), SCOFF questionnaire for disordered eating, Low Energy Availability in Females Questionnaire (LEAF-Q), and a custom questionnaire on injury and illness. Clinical assessment comprised resting metabolic rate (RMR) assessment, dual-energy X-ray absorptiometry-derived body composition and bone mineral density, venous and capillary blood samples, and the Mini International Neuropsychiatric Interview (MINI 7.0.2). Descriptive prevalence statistics are presented.

RESULTS

Almost all (80%) participants (age 19 (range 15-32) years; mass 69.5±10.3 kg; body fat 23.1%±5.0%) demonstrated at least one symptom consistent with RED-S, with 37% exhibiting between two and three symptoms. One participant demonstrated five symptoms. Impaired function of the immunological (28%, n=27), haematological (31%, n=33) and gastrointestinal (47%, n=51) systems were most prevalent. A moderate to high (11%-55%) prevalence of risk of low energy availability was identified via RMR and LEAF-Q, and identified mental illnesses were prevalent in one-third of the assessed cohort.

CONCLUSION

Symptoms described by the RED-S model were prevalent in this cohort, supporting the need for improved awareness, monitoring and management of these symptoms in this population.

Reasons for and Consequences of Low Energy Availability in Female and Male Athletes: Social Environment, Adaptations, and Prevention

Low energy availability (LEA) represents a state in which the body does not have enough energy left to support all physiological functions needed to maintain optimal health. When compared to the normal population, athletes are particularly at risk to experience LEA and the reasons for this are manifold. LEA may result from altered dietary behaviours that are caused by body dissatisfaction, the belief that a lower body weight will result in greater performance, or social pressure to look a certain way. Pressure can also be experienced from the coach, teammates, and in this day and age through social media platforms. While LEA has been extensively described in females and female athletes have started fighting against the pressure to be thin using their social media platforms, evidence shows that male athletes are at risk as well. Besides those obvious reasons for LEA, athletes engaging in sports with high energy expenditure (e.g. rowing or cycling) can unintentionally experience LEA; particularly, when the athletes' caloric intake is not matched with exercise intensity. Whether unintentional or not, LEA may have detrimental consequences on health and performance, because both short-term and long-term LEA induces a variety of maladaptations such as endocrine alterations, suppression of the reproductive axis, mental disorders, thyroid suppression, and altered metabolic responses. Therefore, the aim of this review is to increase the understanding of LEA, including the role of an athlete's social environment and the performance effects related to LEA.

Intake of antioxidant vitamins in women with different physical activity levels

Study aim: The purpose of this study was to compare intake of antioxidant vitamins (A, C, E) in young women with various levels of physical activity.

Material and methods: The study included 3 groups of females: 40 women with no extra physical activity (Sedentary), 40 women involved in regular, moderate sports activities (Recreationally Active) and 40 female athletes competing at an international level (Athletes). Participants’ diet was assessed on the basis of 3-day diet records which were analysed using the computer program ‘Dieta 5.0’. Body composition was evaluated by the bioelectrical impedance analysis (BIA) method.

Results: Athletes were characterized by the lowest body fat and highest lean body mass in comparison with the other groups. They also showed the highest intake of energy, proteins and carbohydrates compared to Active and Sedentary women. The consumption of vitamin A amounted to 180.0% of RDA in Athletes, 98.8% in Recreationally Active and 97.8% in Sedentary women. Vitamin C intake in Athletes equalled 275.0% of RDA, whereas the deficiency of this vitamin was observed in Recreationally Active and Sedentary women (62.3% and 46.1% of RDA, respectively). The study groups showed consumption of vitamin E at the level of 146.7% of AI in Athletes, 115.0% in Recreationally Active and 111.3% in Sedentary women.

Conclusion: Athletes consumed excessive amounts of antioxidant vitamins. Recreationally Active and Sedentary women met the demand for vitamin A and E, but the intake of vitamin C was not sufficient, which could lead to health problems. The current findings also indicate that energy intake was at a low level regardless of the study group.

Low Energy Availability in Athletes 2020: An Updated Narrative Review of Prevalence, Risk, Within-Day Energy Balance, Knowledge, and Impact on Sports Performance

Low energy availability (EA) underpins the female and male athlete triad and relative energy deficiency in sport (RED-S). The condition arises when insufficient calories are consumed to support exercise energy expenditure, resulting in compromised physiological processes, such as menstrual irregularities in active females. The health concerns associated with longstanding low EA include menstrual/libido, gastrointestinal and cardiovascular dysfunction and compromised bone health, all of which can contribute to impaired sporting performance. This narrative review provides an update of our previous review on the prevalence and risk of low EA, within-day energy deficiency, and the potential impact of low EA on performance. The methods to assess EA remain a challenge and contribute to the methodological difficulties in identifying "true" low EA. Screening female athletic groups using a validated screening tool such as the Low Energy Availability in Females Questionnaire (LEAF-Q) has shown promise in identifying endurance athletes at risk of low EA. Knowledge of RED-S and its potential implications for performance is low among coaches and athletes alike. Development of sport and gender-specific screening tools to identify adolescent and senior athletes in different sports at risk of RED-S is warranted. Education initiatives are required to raise awareness among coaches and athletes of the importance of appropriate dietary strategies to ensure that sufficient calories are consumed to support training.

Nutritional Risks Among Female Athletes

Background: Limited research studies have been conducted on nutritional risks among female athletes. Therefore, this literature review focuses on rigorously designed studies that examined nutritional risks among female athletes with further recommendations for athletes, coaches, parents, and health professionals, which would help improve the health of female athletes. Methods: This review evaluates the most recent research on nutritional risk among female athletes. Inclusion criteria included peer-reviewed studies of original research on human subjects 13 years of age or older; sample size of N ≥ 19; and studies with a thorough description of their sample and methods. A systematic search of the databases PubMed and Cochrane for published studies (from year 2000 to year 2019) was conducted to identify articles that met inclusion criteria. Bibliographies of identified articles were also searched for relevant articles. Results: Of the 11 studies that met our inclusion criteria, most were mainly cross-sectional in design with few rigorous controls. Findings reveal that strategies to enhance nutrition patterns among female athletes may be important to avoid risks of disordered eating, eating disorders, low energy availability, and symptoms of relative energy deficiency in sports. In addition, general nutrition knowledge is lacking among athletes, sports teams, and coaches. Conclusions: This review highlights the scarcity of evidence-based, rigorous studies examining nutritional risks among female athletes. Findings suggest that interdisciplinary working groups, comprising physicians, sports dietitians, and other supportive health professionals, would be beneficial for female athletes in helping to improve their overall diet, performance, and health.

Low Energy Availability, Plasma Lipids, and Hormonal Profiles of Recreational Athletes

Black, K, Slater, J, Brown, RC, and Cooke, R. Low energy availability, plasma lipids, and hormonal profiles of recreational athletes. J Strength Cond Res 32(10): 2816-2824, 2018-It has been postulated that low energy availability (LEA) impacts bone health, hormonal concentrations, and cardiovascular function. This study describes the lipid levels, hormonal profiles, and nutrient intakes of recreationally active adults at risk of LEA compared with those not at risk. Thirty-eight women who meet or exceed the New Zealand guidelines for physical activity participated. Each participant completed an online questionnaire including the Low Energy Availability in Females questionnaire (LEAF-Q), demographic questions, and daily exercise to determine energy expenditure. Participants also provided a weighed 3-day diet record, a blood sample analyzed for total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, and cortisol, and a saliva sample analyzed for testosterone. Body composition was assessed using bioelectrical impedance. Those classed as at risk of LEA according to the LEAF-Q showed very likely lower energy availability (at risk: mean, 36.3 [95% confidence interval, 30.8-41.7] kcal·kg·FFMd vs. not at risk: mean, 47.5 [95% CI, 39.5-55.4] kcal·kg·FFMd) and lower calcium intakes (mean, 847 [95% CI, 695-998] mg, vs. mean, 1488 [95% CI, 690-2,286] mg). Those at risk also had a likely small lower T3 concentration of 1.78 (SD: 0.36) nmol·L compared with 2.01 (SD: 0.53) nmol·L for those not at risk. These data suggest that recreationally active female subjects classed as at risk of LEA according to the LEAF-Q also have lower energy availability as determined by diet records and exercise diaries. The results also suggests that those at risk of LEA have reductions in T3, and their low energy intake, in addition to a low calcium intake, could put them at an increased risk of poor bone health.

Nutrition Status of Young Elite Female German Football Players

PURPOSE

To investigate energy intake, energy expenditure, and the nutritional status of young female elite football players using 7-day food and activity records and blood parameters.

METHODS

A total of 56 female elite football players [14.8 (0.7) y] completed the requested food and activity protocols. Misreporting was assessed by the ratio of energy intake to energy expenditure. The food records were analyzed concerning energy and macronutrient and micronutrient intakes, and energy expenditure was calculated using predictive equations. Hematological data and 25-hydroxyvitamin D serum concentrations were determined.

RESULTS

Mean energy intake was 2262 (368) kcal/d [40.5 (7.0) kcal/kg/d] and estimated EE averaged 2403 (195) kcal/d. Fifty-three percent of the players exhibited an energy availability <30 kcal/kg lean body mass; 31% of the athletes consumed <5 g/kg carbohydrates and 34% consumed <1.2 g/kg proteins. A large proportion of players (%) had intakes below the recommended daily allowance of folate (75%), vitamin D (100%), iron (69%), and calcium (59%). Ferritin and 25-hydroxyvitamin D serum levels were below the recommendations of 59% and 38%, respectively.

CONCLUSIONS

A remarkable number of players failed to meet the energy balance and the recommended carbohydrate and protein intakes. Low iron and 25-hydroxyvitamin D serum levels were observed showing a suboptimal nutrition status of some young female football players. As a consequence, strategies have to be developed for a better information and application of sport nutrition practice among young female football players.

Body Composition of Women's Ice Hockey Players: Comparison of Estimates Using Skinfolds and iDXA

Gilenstam, K and Geithner, CA. Body composition of women's ice hockey players: comparison of estimates using skinfolds and iDXA. J Strength Cond Res 33(9): 2496-2502, 2019-The purpose of this study was to compare percent fat (% fat) estimates from anthropometric equations using skinfolds (SKF) in women's ice hockey players with estimates obtained from Lunar iDXA. Data were collected on 19 elite female Swedish hockey players (mean age ± SD = 18.4 ± 2.4 years). Four SKF (triceps, abdominal, suprailiac, and thigh) were measured within 2 hours of iDXA assessments. The % fat estimates from iDXA and 4 anthropometric equations were compared using paired t tests, and a 1-way analysis of variance was used to compare % fat estimates from the anthropometric equations. Bland-Altman analyses were used to assess agreement between % fat estimates from SKF and iDXA. The significance level was set a priori at p ≤ 0.05. The % fat estimates from anthropometric equations were significantly lower than those from iDXA (mean ± SD: 26.85 ± 4.93%, p = 0.000). Bland-Altman analyses indicated mean differences of -7.96 to -10.13 percentage points between anthropometric equations and iDXA. Estimates of % fat from anthropometric equations (range: 16.72-18.89%) were within the range reported in earlier studies using the sum of 7 SKF. Thus, SKF offer a reasonable alternative to iDXA for this population but result in underestimates of % fat relative to iDXA. Strength and conditioning coaches should use the same body composition assessment method consistently, and interpret the results with caution, as they are estimates and not true values.

The female athlete triad: special considerations for adolescent female athletes

The number of adolescent girls participating in sports has dramatically increased throughout the last few decades. In the early 1990's, an association between amenorrhea, osteoporosis, and disordered eating was recognized and eventually labeled the 'Female Athlete Triad'. In 1997, the Task Force on Women's Issues of American College of Sports Medicine (ACSM) published a position statement on this triad of conditions that were becoming increasingly more prevalent amongst female athletes. Initially, the 'Female Athlete Triad' was characterized by disordered eating, amenorrhea, and osteoporosis. However, as the number of adolescent female athletes has continued to grow, there has been further research and investigation into this field and the triad has evolved in definition. It is essential for all health care practitioners and other professionals who care for adolescent athletes to be attentive to the clinical signs, detection, evaluation, and management of the female athlete triad, as the sequelae can have a significant impact on the health and well-being of a young person both in the short and long-term.