1
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Suzuki D, Suzuki Y. Identifying and Analyzing Low Energy Availability in Athletes: The Role of Biomarkers and Red Blood Cell Turnover. Nutrients 2024; 16:2273. [PMID: 39064716 PMCID: PMC11279570 DOI: 10.3390/nu16142273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Revised: 06/28/2024] [Accepted: 07/12/2024] [Indexed: 07/28/2024] Open
Abstract
Low energy availability (LEA) is a growing concern that can lead to several problems for athletes. However, adaptation to LEA occurs to maintain balance over time, making diagnosis difficult. In this review, we categorize LEA into two phases: the initial phase leading to adaptation and the phase in which adaptation is achieved and maintained. We review the influence of LEA on sports performance and health and discuss biomarkers for diagnosing LEA in each phase. This review also proposes future research topics for diagnosing LEA, with an emphasis on the recently discovered association between red blood cell turnover and LEA.
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Affiliation(s)
- Daisuke Suzuki
- Department of Biological Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Fuchu 183-8509, Tokyo, Japan;
| | - Yoshio Suzuki
- Graduate School of Health and Sports Science, Juntendo University, Inzai 276-1695, Chiba, Japan
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2
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Baranauskas M, Kupčiūnaitė I, Lieponienė J, Stukas R. Association between Variation in Body Fat Mass Magnitude and Intake of Nutrients, including Carbohydrates, Fat, and B Vitamins, in a Cohort of Highly Trained Female Athletes. Foods 2023; 12:4152. [PMID: 38002209 PMCID: PMC10670790 DOI: 10.3390/foods12224152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/31/2023] [Accepted: 11/14/2023] [Indexed: 11/26/2023] Open
Abstract
The most common sports nutrition strategies were constructed not only for maximizing musculoskeletal adaptations to exercise, but also to minimize health risks in athletes. Given the lack of research highlighting the potential effects of the intake of carbohydrates, fats, and B vitamins on body fat percentage in a population of female athletes, this study aimed to elucidate whether the intake of macronutrients and B vitamins could be associated with the variation in body fat percentage in a cohort of professional female athletes. This cross-sectional study was weighted to represent Lithuanian elite female athletes (n = 89). The dietary assessment of the female athletes was carried out using a 3-day dietary recall method. Their body composition was assessed using the bioelectrical impedance analysis method. For females, the reported average intakes of energy, carbohydrates, protein, and fat were 2475 kcal/day, 5.1 g/kg/day, 1.5 g/kg/day, and 36.7%, respectively. Excess B vitamin intake was revealed, ranging within plus 1-2 standard deviations (SDs) around the mean requirements. As a consequence, excessive body fat percentage was potentially factored as a negative outcome in maintaining optimal body composition in female athletes. Multivariate logistic regression analysis of a sample of female athletes revealed that, despite a slightly positive energy balance (∆ 95 kcal/day), the carbohydrate-deficient diet (adjusted odds ratio (aOR) 0.3, 95% confidence interval (CI) 0.1; 0.7), along with higher intakes of vitamin B1 (aOR 2.9, 95% CI 2.6; 7.8), vitamin B2 (aOR 6.7, 95% CI 1.1; 8.3), and vitamin B3 (aOR 1.8, 95% CI 1.4; 7.8) from food, was associated with a lower percentage of body fat. Therefore, more attention should be given to the intake of B vitamins in professional athletes with a range of body fat mass percentages for the purpose of achieving long-term goals of maintaining body composition and fitness.
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Affiliation(s)
- Marius Baranauskas
- Faculty of Biomedical Sciences, State Higher Education Institution Panevėžys College, 35200 Panevėžys, Lithuania; (I.K.); (J.L.)
| | - Ingrida Kupčiūnaitė
- Faculty of Biomedical Sciences, State Higher Education Institution Panevėžys College, 35200 Panevėžys, Lithuania; (I.K.); (J.L.)
| | - Jurgita Lieponienė
- Faculty of Biomedical Sciences, State Higher Education Institution Panevėžys College, 35200 Panevėžys, Lithuania; (I.K.); (J.L.)
| | - Rimantas Stukas
- Department of Public Health, Institute of Health Sciences, Faculty of Medicine, Vilnius University, 01513 Vilnius, Lithuania;
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3
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Wyatt PM, Drager K, Groves EM, Stellingwerff T, Billington EO, Boyd SK, Burt LA. Comparison of Bone Quality Among Winter Endurance Athletes with and Without Risk Factors for Relative Energy Deficiency in Sport (REDs): A Cross-Sectional Study. Calcif Tissue Int 2023; 113:403-415. [PMID: 37578531 DOI: 10.1007/s00223-023-01120-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 07/29/2023] [Indexed: 08/15/2023]
Abstract
Relative Energy Deficiency in Sport (REDs) is a syndrome describing the relationship between prolonged and/or severe low energy availability and negative health and performance outcomes. The high energy expenditures incurred during training and competition put endurance athletes at risk of REDs. The objective of this study was to investigate differences in bone quality in winter endurance athletes classified as either low-risk versus at-risk for REDs. Forty-four participants were recruited (M = 18; F = 26). Bone quality was assessed at the distal radius and tibia using high resolution peripheral quantitative computed tomography (HR-pQCT), and at the hip and spine using dual X-ray absorptiometry (DXA). Finite element analysis was used to estimate bone strength. Participants were grouped using modified criteria from the REDs Clinical Assessment Tool Version 1. Fourteen participants (M = 3; F = 11), were classified as at-risk of REDs (≥ 3 risk factors). Measured with HR-pQCT, cortical bone area (radius) and bone strength (radius and tibia) were 6.8%, 13.1% and 10.3% lower (p = 0.025, p = 0.033, p = 0.027) respectively, in at-risk compared with low-risk participants. Using DXA, femoral neck areal bone density was 9.4% lower in at-risk compared with low-risk participants (p = 0.005). At-risk male participants had 21.9% lower femoral neck areal bone density (via DXA) than low-risk males (p = 0.020) with no significant differences in females. Overall, 33.3% of athletes were at-risk for REDs and had lower bone quality than those at low-risk.
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Affiliation(s)
- Paige M Wyatt
- McCaig Institute for Bone and Joint Health, University of Calgary, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada
- Canadian Sport Institute Calgary, Calgary, AB, Canada
| | - Kelly Drager
- Canadian Sport Institute Calgary, Calgary, AB, Canada
| | - Erik M Groves
- Canadian Sport Institute Calgary, Calgary, AB, Canada
| | - Trent Stellingwerff
- Canadian Sport Institute Pacific, Victoria, BC, Canada
- Department of Exercise Science, Physical and Health Education, University of Victoria, Victoria, BC, Canada
| | - Emma O Billington
- McCaig Institute for Bone and Joint Health, University of Calgary, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada
- Division of Endocrinology and Metabolism, Cumming School of Medicine, University of Calgary, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada
| | - Steven K Boyd
- McCaig Institute for Bone and Joint Health, University of Calgary, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada
- Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Lauren A Burt
- McCaig Institute for Bone and Joint Health, University of Calgary, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.
- Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
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4
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Baranauskas M, Kupčiūnaitė I, Stukas R. Dietary Intake of Protein and Essential Amino Acids for Sustainable Muscle Development in Elite Male Athletes. Nutrients 2023; 15:4003. [PMID: 37764784 PMCID: PMC10535035 DOI: 10.3390/nu15184003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/08/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023] Open
Abstract
Athletes need to develop a relatively high muscle mass and low body adipose tissue for the sake of better athletic performance. A full range of nine essential amino acids and eleven non-essential amino acids have to attend in appropriate amounts for protein biosynthesis. The aim of the observational comparative cross-sectional study was to assess the association between the diet quality profile and training-induced muscle mass estimated by bioelectrical impedance among elite male athletes. The research sample comprised 18.1 ± 3.1 year-old Lithuanian professional male athletes (n = 234). The study participants were enrolled to complete 24-h dietary recalls of three non-consecutive days. The body composition was assessed using the bioelectrical impedance analysis (BIA) method. The present study showed a significant insufficiency of the mean carbohydrate intake of 5.7 g/kg/day in a group of aerobic male athletes. The lower muscle mass of aerobic male athletes was related to the lower-carbohydrate diet (adjusted odd ratio (ORadj) 0.3; 95% confidence interval (CI): 0.1-0.7). The mean protein intake of 1.8 g/kg/day was optimal for anabolism in the samples of both anaerobic and aerobic male athletes. The protein intake in appropriate doses was potentially associated with an increase in muscle mass only in anaerobic male athletes (ORadj 2.2; 95% CI: 1.3-3.7). The positive relationship was revealed between the possible muscle mass gain and the increased intakes of amino acids such as isoleucine and histidine among anaerobic athletes (ORadj 2.9; 95% CI: 1.1-4.7 and ORadj 2.9; 95% CI: 1.0-4.3, respectively). An inverse feasible association was indicated between a higher intake of valine and lower muscle mass quantities among anaerobic male athletes (ORadj 0.1; 95% CI: 0.1-0.5). The recommendations for sports nutritionists should emphasize the necessity of advising professional athletes on dietary strategies on how to manipulate dietary amino acid composition with respect to achieving long-term body composition goals.
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Affiliation(s)
- Marius Baranauskas
- Faculty of Biomedical Sciences, Panevėžys University of Applied Sciences, 35200 Panevėžys, Lithuania;
| | - Ingrida Kupčiūnaitė
- Faculty of Biomedical Sciences, Panevėžys University of Applied Sciences, 35200 Panevėžys, Lithuania;
| | - Rimantas Stukas
- Institute of Health Sciences, Faculty of Medicine, Department of Public Health, Vilnius University, 01513 Vilnius, Lithuania;
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5
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Gild ML, Stuart M, Clifton-Bligh RJ, Kinahan A, Handelsman DJ. Thyroid Hormone Abuse in Elite Sports: The Regulatory Challenge. J Clin Endocrinol Metab 2022; 107:e3562-e3573. [PMID: 35438767 PMCID: PMC9387720 DOI: 10.1210/clinem/dgac223] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Indexed: 11/19/2022]
Abstract
Abuse of androgens and erythropoietin has led to hormones being the most effective and frequent class of ergogenic substances prohibited in elite sports by the World Anti-Doping Agency (WADA). At present, thyroid hormone (TH) abuse is not prohibited, but its prevalence among elite athletes and nonprohibited status remains controversial. A corollary of prohibiting hormones for elite sports is that endocrinologists must be aware of a professional athlete's risk of disqualification for using prohibited hormones and/or to certify Therapeutic Use Exemptions, which allow individual athletes to use prohibited substances for valid medical indications. This narrative review considers the status of TH within the framework of the WADA Code criteria for prohibiting substances, which requires meeting 2 of 3 equally important criteria of potential performance enhancement, harmfulness to health, and violation of the spirit of sport. In considering the valid clinical uses of TH, the prevalence of TH use among young adults, the reason why some athletes seek to use TH, and the pathophysiology of sought-after and adverse effects of TH abuse, together with the challenges of detecting TH abuse, it can be concluded that, on the basis of present data, prohibition of TH in elite sport is neither justified nor feasible.
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Affiliation(s)
- Matti L Gild
- Faculty of Medicine and Health, University of Sydney, Sydney 2006, Australia
- Department of Diabetes and Endocrinology, Royal North Shore Hospital, Sydney 2065, Australia
- Cancer Genetics, Kolling Institute of Medical Research, St Leonards 2065, Australia
| | - Mark Stuart
- Division of Medicine, Centre for Metabolism and Inflammation, University College London, WC1E 6BT, UK
- International Testing Agency Lausanne, Lausanne 1007, Switzerland
| | - Roderick J Clifton-Bligh
- Faculty of Medicine and Health, University of Sydney, Sydney 2006, Australia
- Department of Diabetes and Endocrinology, Royal North Shore Hospital, Sydney 2065, Australia
- Cancer Genetics, Kolling Institute of Medical Research, St Leonards 2065, Australia
| | | | - David J Handelsman
- Correspondence: Professor David Handelsman, ANZAC Research Institute, Department of Andrology, Concord Hospital, Sydney, New South Wales, Australia.
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6
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Enea C, Arc C, Delpech N. Les spécificités hormonales de la sportive de haut niveau : adapter la prise en charge pour optimiser la performance. Sci Sports 2022. [DOI: 10.1016/j.scispo.2021.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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7
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De Souza MJ, Strock NCA, Ricker EA, Koltun KJ, Barrack M, Joy E, Nattiv A, Hutchinson M, Misra M, Williams NI. The Path Towards Progress: A Critical Review to Advance the Science of the Female and Male Athlete Triad and Relative Energy Deficiency in Sport. Sports Med 2021; 52:13-23. [PMID: 34665451 DOI: 10.1007/s40279-021-01568-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/12/2021] [Indexed: 12/01/2022]
Abstract
Energy status plays a key role in the health of athletes and exercising individuals. Energy deficiency/low energy availability (EA), referring to a state in which insufficient energy intake and/or excessive exercise energy expenditure has resulted in compensatory metabolic adaptations to conserve fuel, can affect numerous physiological systems in women and men. The Female Athlete Triad, Male Athlete Triad, and Relative Energy Deficiency in Sport (RED-S) models conceptualize the effects of energy deficiency in athletes, and each model has strengths and limitations. For instance, the Female Athlete Triad model depicts relationships between low EA, reproductive, and bone health, underpinning decades of experimental evidence, but may be perceived as limited in scope, while the more recent RED-S model proposes a wider range of potential health effects of low EA, though many model components require more robust scientific justification. This critical review summarizes current evidence regarding the effects of energy deficiency on athlete health by addressing the quality of the underlying science, the strengths and limitations of each model, and highlighting areas where future research is needed to advance the field. With the health and wellness of athletes and exercising individuals as the overarching priority, we conclude with specific steps that will help focus future research on the Female and Male Athlete Triad and RED-S, and encourage all researchers, clinicians, and practitioners to collaborate to support the common goal of promoting the highest quality science and evidence-based medicine in pursuit of the advancement of athletes' health, well-being, and performance.
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Affiliation(s)
- Mary Jane De Souza
- Department of Kinesiology and Physiology, Pennsylvania State University, University Park, PA, USA
| | - Nicole C A Strock
- Department of Kinesiology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Emily A Ricker
- Consortium for Health and Military Performance, Department of Military and Emergency Medicine, F. Edward Hébert School of Medicine, Uniformed Services University, Bethesda, USA.,Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, USA
| | - Kristen J Koltun
- Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michelle Barrack
- Department of Family and Consumer Sciences, California State University Long Beach, Long Beach, CA, USA
| | | | - Aurelia Nattiv
- Department of Sports Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Mark Hutchinson
- Department of Orthopedics and Sports Medicine, University of Illinois Chicago, Chicago, IL, USA
| | - Madhusmita Misra
- Division of Pediatric Endocrinology, Massachusetts General Hospital, Boston, MA, USA
| | - Nancy I Williams
- Department of Kinesiology, Pennsylvania State University, University Park, PA, 16802, USA.
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8
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Holtzman B, Ackerman KE. Recommendations and Nutritional Considerations for Female Athletes: Health and Performance. Sports Med 2021; 51:43-57. [PMID: 34515972 PMCID: PMC8566643 DOI: 10.1007/s40279-021-01508-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2021] [Indexed: 11/29/2022]
Abstract
Optimal nutrition is an important aspect of an athlete’s preparation to achieve optimal health and performance. While general concepts about micro- and macronutrients and timing of food and fluids are addressed in sports science, rarely are the specific effects of women’s physiology on energy and fluid needs highly considered in research or clinical practice. Women differ from men not only in size, but in body composition and hormonal milieu, and also differ from one another. Their monthly hormonal cycles, with fluctuations in estrogen and progesterone, have varying effects on metabolism and fluid retention. Such cycles can change from month to month, can be suppressed with exogenous hormones, and may even be manipulated to capitalize on ideal timing for performance. But before such physiology can be manipulated, its relationship with nutrition and performance must be understood. This review will address general concepts regarding substrate metabolism in women versus men, common menstrual patterns of female athletes, nutrient and hydration needs during different phases of the menstrual cycle, and health and performance issues related to menstrual cycle disruption. We will discuss up-to-date recommendations for fueling female athletes, describe areas that require further exploration, and address methodological considerations to inform future work in this important area.
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Affiliation(s)
- Bryan Holtzman
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Female Athlete Program, Division of Sports Medicine, Boston Children's Hospital, Boston, MA, USA
| | - Kathryn E Ackerman
- Female Athlete Program, Division of Sports Medicine, Boston Children's Hospital, Boston, MA, USA. .,Neuroendocrine Unit, Massachusetts General Hospital, Boston, MA, USA. .,Harvard Medical School, Boston, MA, USA.
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9
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Wardle SL, O'Leary TJ, McClung JP, Pasiakos SM, Greeves JP. Feeding female soldiers: Consideration of sex-specific nutrition recommendations to optimise the health and performance of military personnel. J Sci Med Sport 2021; 24:995-1001. [PMID: 34452842 DOI: 10.1016/j.jsams.2021.08.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 06/25/2021] [Accepted: 08/11/2021] [Indexed: 12/25/2022]
Abstract
Appropriate nutrition recommendations are required to optimise the health and performance of military personnel, yet limited data are available on whether male and female military personnel have different nutrition requirements. OBJECTIVES To consider the evidence for sex-specific nutrition requirements to optimise the health and performance of military personnel. DESIGN Narrative review. METHODS Published literature was reviewed, with a focus on sex-specific requirements, in the following areas: nutrition for optimising muscle mass and function, nutrition during energy deficit, and nutrition for reproductive and bone health. RESULTS There are limited data on sex differences in protein requirements but extant data suggest that, despite less muscle mass, on average, in women, sex-specific protein feeding strategies are not required to optimise muscle mass in military-aged individuals. Similarly, despite sex differences in metabolic and endocrine responses to energy deficit, current data do not suggest a requirement for sex-specific feeding strategies during energy deficit. Energy deficit impairs health and performance, most notably bone and reproductive health and these impairments are greater for women. Vitamin D, iron and calcium are important nutrients to protect the bone health of female military personnel due to increased risk of stress fracture. CONCLUSIONS Women have an increased incidence of bone injuries, less muscle mass and are more susceptible to the negative effects of energy deficit, including compromised reproductive health. However, there are limited data on sex differences in response to various nutrition strategies designed to improve these elements of health and performance. Future studies should evaluate whether sex-specific feeding recommendations are required.
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Affiliation(s)
- Sophie L Wardle
- Army Health and Performance Research, Army Headquarters, United Kingdom; Division of Surgery and Interventional Science, University College London, United Kingdom.
| | - Thomas J O'Leary
- Army Health and Performance Research, Army Headquarters, United Kingdom; Division of Surgery and Interventional Science, University College London, United Kingdom
| | - James P McClung
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, United States of America
| | - Stefan M Pasiakos
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, United States of America
| | - Julie P Greeves
- Army Health and Performance Research, Army Headquarters, United Kingdom; Division of Surgery and Interventional Science, University College London, United Kingdom; Norwich Medical School, University of East Anglia, United Kingdom
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10
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Kopp C. Relatives Energiedefizit im Sport (RED-S). GYNAKOLOGISCHE ENDOKRINOLOGIE 2021. [DOI: 10.1007/s10304-021-00396-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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11
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Sharps FRJ, Wilson LJ, Graham CAM, Curtis C. Prevalence of disordered eating, eating disorders and risk of low energy availability in professional, competitive and recreational female athletes based in the United Kingdom. Eur J Sport Sci 2021; 22:1445-1451. [PMID: 34121611 DOI: 10.1080/17461391.2021.1943712] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
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.
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Affiliation(s)
| | | | - Catherine Anna-Marie Graham
- Oxford Brookes Centre for Nutrition and Health, Faculty of Health and Life Sciences, Department of Sport, Health and Social Work, Oxford Brookes University, Oxford, UK
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12
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Karl JP, Margolis LM, Fallowfield JL, Child RB, Martin NM, McClung JP. Military nutrition research: Contemporary issues, state of the science and future directions. Eur J Sport Sci 2021; 22:87-98. [PMID: 33980120 DOI: 10.1080/17461391.2021.1930192] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The importance of diet and nutrition to military readiness and performance has been recognized for centuries as dietary nutrients sustain health, protect against illness, and promote resilience, performance and recovery. Contemporary military nutrition research is increasingly inter-disciplinary with emphasis often placed on the broad topics of (1) determining operational nutrition requirements in all environments, (2) characterizing nutritional practices of military personnel relative to the required (role/environment) standards, and (3) developing strategies for improving nutrient delivery and individual choices. This review discusses contemporary issues shared internationally by military nutrition research programmes, and highlights emerging topics likely to influence future military nutrition research and policy. Contemporary issues include improving the diet quality of military personnel, optimizing operational rations, and increasing understanding of biological factors influencing nutrient requirements. Emerging areas include the burgeoning field of precision nutrition and its technological enablers.
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Affiliation(s)
- J Philip Karl
- Military Nutrition Division, United States Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Lee M Margolis
- Military Nutrition Division, United States Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Joanne L Fallowfield
- Environmental Medicine and Science Division, Institute of Naval Medicine, Alverstoke, Hampshire, UK
| | - Robert B Child
- School of Chemical Engineering, University of Birmingham, Birmingham, UK
| | - Nicola M Martin
- New Zealand Army, New Zealand Defence Force, Upper Hutt, New Zealand
| | - James P McClung
- Military Nutrition Division, United States Army Research Institute of Environmental Medicine, Natick, MA, USA
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13
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Commentary in Response to "A Review of Nonpharmacological Strategies in the Treatment of Relative Energy Deficiency in Sport". Int J Sport Nutr Exerc Metab 2021; 31:380-382. [PMID: 34021096 DOI: 10.1123/ijsnem.2021-0084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 03/24/2021] [Indexed: 11/18/2022]
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14
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Gallagher KA, Sonneville KR, Hazzard VM, Carson TL, Needham BL. Evaluating gender bias in an eating disorder risk assessment questionnaire for athletes. Eat Disord 2021; 29:29-41. [PMID: 31079562 DOI: 10.1080/10640266.2019.1613846] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Due to stigma, eating disorders are under-researched, underdiagnosed and undertreated among men. This is particularly pertinent among athletes, as athletic goals are a major risk factor for disordered eating in men. This gender stereotype may be reinforced by eating disorder risk assessment tools that better reflect female symptoms. We examine an eating disorder risk assessment questionnaire in a population of athletes to assess both (1) gender bias in individual items and (2) gender differences on a cognitive and behavioral subscale, identified through a factor analysis. Controlling for eating disorder risk, we found that female gender significantly predicted high risk scores on four items; male gender significantly predicted high risk scores on four other items. We also found that women were more likely to score above the median on a cognitive subscale than men with the same level of eating disorder risk, while men were more likely to score above the median on a behavioral subscale. These results may be applied practically to allow eating disorder risk assessment tools to better capture eating disorder risk independent of gender. These methods may be applied to other questionnaires and other social identities, to expand the scope of eating disorder research and treatment.
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Affiliation(s)
| | | | | | - Traci L Carson
- School of Public Health, University of Michigan , Ann Arbor, MI, USA
| | - Belinda L Needham
- School of Public Health, University of Michigan , Ann Arbor, MI, USA
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15
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Ito S, Fukumoto T, Imagita H. Physical Fitness Testing and Screening Reveal a Gateway to Identify Locomotive Disorders: Retrospective Study of a Japanese Elementary School Population. Glob Pediatr Health 2021; 8:2333794X211062459. [PMID: 35005100 PMCID: PMC8728768 DOI: 10.1177/2333794x211062459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/03/2021] [Indexed: 11/16/2022] Open
Abstract
This retrospective epidemiological study investigated the relationship between
physical fitness testing and locomotive disorder screening results among
elementary school children in Japan. The test and screening results of 1033
children from a single elementary school between 2016 and 2018 were examined.
Multiple regression analysis was performed for each gender of children of grades
third and fourth to generate receiver-operating characteristic curves. Of the 69
children with parent-identified locomotor problems, 29 (42%) had physical
fitness test score of mean ± 2 SD. For the standing long jump test in fourth
grade girls, the results differed significantly (P < .001;
cut-off, 127 cm) for children whose parents did (n = 7) and did not (n = 84)
suspect a possible locomotive disorder. Physical fitness testing in combination
with school-based screening for locomotive disorders may be useful for
identifying and accurately diagnosing these disorders in children.
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Affiliation(s)
- Syuro Ito
- Sakai City Board of Education Secretariat, Osaka Prefecture, Japan
- Kio University, Koryo-cho, Kitakatsuragi-gun, Nara Prefecture, Japan
| | - Takahiko Fukumoto
- Kio University, Koryo-cho, Kitakatsuragi-gun, Nara Prefecture, Japan
| | - Hidetaka Imagita
- Kio University, Koryo-cho, Kitakatsuragi-gun, Nara Prefecture, Japan
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Comparison of Female Athlete Triad (Triad) and Relative Energy Deficiency in Sport (RED-S): a Review of Low Energy Availability, Multidisciplinary Awareness, Screening Tools and Education. CURRENT PHYSICAL MEDICINE AND REHABILITATION REPORTS 2020. [DOI: 10.1007/s40141-020-00296-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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17
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Abstract
Respiratory and gastrointestinal infections limit an athlete's availability to train and compete. To better understand how sick an athlete will become when they have an infection, a paradigm recently adopted from ecological immunology is presented that includes the concepts of immune resistance (the ability to destroy microbes) and immune tolerance (the ability to dampen defence yet control infection at a non-damaging level). This affords a new theoretical perspective on how nutrition may influence athlete immune health; paving the way for focused research efforts on tolerogenic nutritional supplements to reduce the infection burden in athletes. Looking through this new lens clarifies why nutritional supplements targeted at improving immune resistance in athletes show limited benefits: evidence supporting the old paradigm of immune suppression in athletes is lacking. Indeed, there is limited evidence that the dietary practices of athletes suppress immunity, e.g. low-energy availability and train- or sleep-low carbohydrate. It goes without saying, irrespective of the dietary preference (omnivorous, vegetarian), that athletes are recommended to follow a balanced diet to avoid a frank deficiency of a nutrient required for proper immune function. The new theoretical perspective provided sharpens the focus on tolerogenic nutritional supplements shown to reduce the infection burden in athletes, e.g. probiotics, vitamin C and vitamin D. Further research should demonstrate the benefits of candidate tolerogenic supplements to reduce infection in athletes; without blunting training adaptations and without side effects.
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Low Bone Mineral Density in Elite Female Athletes With a History of Secondary Amenorrhea in Their Teens. Clin J Sport Med 2020; 30:245-250. [PMID: 32341292 DOI: 10.1097/jsm.0000000000000571] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine whether secondary amenorrhea during teenage years influences bone mineral density (BMD) in female athletes in their 20s. DESIGN Original research. SETTING Japan Institute of Sports Sciences. PARTICIPANTS Two hundred ten elite female athletes older than 20 years were included in the study. MAIN OUTCOME MEASURES Information on the participants' past (ie, during their teenage years) and current menstrual cycle, training time, history of stress fractures, and blood tests for hormones received was obtained. Bone mineral density of the lumbar spine was evaluated by dual-energy x-ray absorptiometry; low BMD was defined as a Z-score ≤-1. We investigated the correlation factors for low BMD in athletes in their 20s by univariable and multivariable logistic regression analysis. RESULTS A total of 39 (18.6%) female athletes had low BMD. Secondary amenorrhea in their teens [odds ratio (OR), 7.11, 95% confidence interval (CI), 2.38-21.24; P < 0.001] and present body mass index (BMI) (OR, 0.56, 95% CI, 0.42-0.73; P < 0.001) were independent correlation factors for low BMD in the multivariable logistic regression analysis. The average Z-score for those with secondary amenorrhea in their teens and 20s, secondary amenorrhea in their 20s only, and regular menstruation was -1.56 ± 1.00, -0.45 ± 1.21, and 0.82 ± 1.11 g/cm, respectively. CONCLUSIONS Secondary amenorrhea for at least 1 year during teenage years in female athletes and BMI at present was strongly associated with low BMD in their 20s.
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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. Int J Sport Nutr Exerc Metab 2020; 30:229–234. [DOI: 10.1123/ijsnem.2019-0284] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 01/10/2020] [Accepted: 01/10/2020] [Indexed: 11/18/2022]
Abstract
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.
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Nose-Ogura S, Yoshino O, Kanatani M, Dohi M, Tabei K, Harada M, Hiraike O, Kawahara T, Osuga Y, Fujii T. Effect of transdermal estradiol therapy on bone mineral density of amenorrheic female athletes. Scand J Med Sci Sports 2020; 30:1379-1386. [PMID: 32285553 DOI: 10.1111/sms.13679] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 02/01/2020] [Accepted: 03/27/2020] [Indexed: 12/25/2022]
Abstract
BACKGROUND The effects of transdermal estradiol treatment (HT) in amenorrheic athletes (AA) with low body weight (BW) and low bone mineral density (BMD) are unknown. PURPOSE To investigate whether HT increases BMD in AA with low BW and to compare the results with levels in AA who have recovered spontaneous menstruation (SM). METHODS Female athletes (n = 151) were recruited at the Japan Institute of Sports Sciences and the University of Tokyo. All participants were divided into four groups: an AA group (untreated group) (n = 36), a HT group (n = 55), a SM group (n = 21), and an eumenorrheic athletes (EA) group (n = 39). Height, body weight, blood tests, and dual-energy X-ray absorptiometry were measured at baseline and after 12 months. The HT group was treated daily for 12 months with transdermal estrogen therapy. In addition, participants received oral progestin for 7 days once every 3 months. RESULTS After 12 months, BMD in the AA group was significantly lower than at baseline; however, BMD in the other three groups was significantly higher than at baseline. The ratio of the change in BMD values before and after 12 months was -1.6 ± 3.2% for the AA group, 5.3 ± 8.7% for the HT group, 11.1 ± 8.9% for the SM group, and 2.3 ± 5.7% for the EA group. The rate of change in BMD values in the SM group was greater than that in the HT group. CONCLUSION HT increased BMD in AA with low BW, and the increase in those with SM was greater than that in those treated with HT.
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Affiliation(s)
- Sayaka Nose-Ogura
- Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan.,Sports Medical Center, Japan Institute of Sports Sciences, Tokyo, Japan
| | - Osamu Yoshino
- Department of Obstetrics and Gynecology, Kitasato University School of Medicine, Kanagawa, Japan
| | - Mayuko Kanatani
- Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan
| | - Michiko Dohi
- Sports Medical Center, Japan Institute of Sports Sciences, Tokyo, Japan
| | - Katsuyuki Tabei
- Department of Radiology, The University of Tokyo Hospital, Tokyo, Japan
| | - Miyuki Harada
- Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan
| | - Osamu Hiraike
- Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan
| | - Takashi Kawahara
- Sports Medical Center, Japan Institute of Sports Sciences, Tokyo, Japan
| | - Yutaka Osuga
- Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan
| | - Tomoyuki Fujii
- Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan
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21
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McGuire A, Warrington G, Doyle L. Low energy availability in male athletes: A systematic review of incidence, associations, and effects. TRANSLATIONAL SPORTS MEDICINE 2020. [DOI: 10.1002/tsm2.140] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Amy McGuire
- Department of Sport and Exercise Science Waterford Institute of Technology Waterford Ireland
| | - Giles Warrington
- Department of Physical Education and Social Sciences University of Limerick Limerick Ireland
- Sport and Human Performance Research Centre Health Research Institute University of Limerick Limerick Ireland
| | - Lorna Doyle
- Department of Sport and Exercise Science Waterford Institute of Technology Waterford Ireland
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22
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Loucks AB. Exercise Training in the Normal Female: Effects of Low Energy Availability on Reproductive Function. ENDOCRINOLOGY OF PHYSICAL ACTIVITY AND SPORT 2020. [DOI: 10.1007/978-3-030-33376-8_11] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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23
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Abstract
BACKGROUND Effective injury prevention measures for running-related injuries (RRIs) have not yet been identified. More insight into the opinions of runners about injury prevention might help to develop effective injury prevention programs that are supported by the target population. OBJECTIVES To describe the opinions of recreational runners on different components of injury prevention, and to identify the barriers to and facilitators of injury prevention in adult recreational runners. METHODS In this comparative cross-sectional study, a single questionnaire was sent to 2378 recreational runners. The questionnaire contained questions about their interests, actions undertaken, and perceived barriers to and facilitators of injury prevention. Descriptive analyses were used to examine differences with regard to sex, age, and previous RRIs. RESULTS One thousand thirty-four adult recreational runners (43.5%) responded to the questionnaire. Runners with previous RRIs were more likely to rate injury prevention as very useful than runners who had never sustained an RRI (76.8% versus 63.6%, P<.001). In total, 81.8% of the participants indicated that they already performed preventive measures, including changes to training schedules (65.4%) and warming up and cooling down (57.8%). Most frequently reported barriers to injury prevention were "not knowing what to do" (45.2%) and "no history of RRI" (34.6%). The most important facilitator was an injury (60.1%). Women more often preferred information via a trainer or running store than did men, while men more frequently preferred websites or e-mail. CONCLUSION The majority of runners rated injury prevention as important. To increase effectiveness, future prevention programs should be developed with an awareness of the barriers and facilitators experienced by adult runners. J Orthop Sports Phys Ther 2019;49(10):736-742. Epub 23 Aug 2019. doi:10.2519/jospt.2019.9029.
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25
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Koltun KJ, Strock NCA, Southmayd EA, Oneglia AP, Williams NI, De Souza MJ. Comparison of Female Athlete Triad Coalition and RED-S risk assessment tools. J Sports Sci 2019; 37:2433-2442. [DOI: 10.1080/02640414.2019.1640551] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Kristen J. Koltun
- Women’s Health and Exercise Lab, Department of Kinesiology, College of Health and Human Development, The Pennsylvania State University, University Park, PA, USA
| | - Nicole C. A. Strock
- Women’s Health and Exercise Lab, Department of Kinesiology, College of Health and Human Development, The Pennsylvania State University, University Park, PA, USA
| | - Emily A. Southmayd
- Women’s Health and Exercise Lab, Department of Kinesiology, College of Health and Human Development, The Pennsylvania State University, University Park, PA, USA
| | - Andrew P. Oneglia
- Women’s Health and Exercise Lab, Department of Kinesiology, College of Health and Human Development, The Pennsylvania State University, University Park, PA, USA
| | - Nancy I. Williams
- Women’s Health and Exercise Lab, Department of Kinesiology, College of Health and Human Development, The Pennsylvania State University, University Park, PA, USA
| | - Mary Jane De Souza
- Women’s Health and Exercise Lab, Department of Kinesiology, College of Health and Human Development, The Pennsylvania State University, University Park, PA, USA
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Williams NI, Koltun KJ, Strock NCA, De Souza MJ. Female Athlete Triad and Relative Energy Deficiency in Sport: A Focus on Scientific Rigor. Exerc Sport Sci Rev 2019; 47:197-205. [DOI: 10.1249/jes.0000000000000200] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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27
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Nose-Ogura S, Yoshino O, Dohi M, Kigawa M, Harada M, Hiraike O, Onda T, Osuga Y, Fujii T, Saito S. Risk factors of stress fractures due to the female athlete triad: Differences in teens and twenties. Scand J Med Sci Sports 2019; 29:1501-1510. [PMID: 31100189 DOI: 10.1111/sms.13464] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 04/20/2019] [Accepted: 05/13/2019] [Indexed: 11/27/2022]
Abstract
BACKGROUND The female athlete triad (Triad), defined by the American College of Sports Medicine as low energy availability (LEA) with or without disordered eating, menstrual dysfunction, and low bone mineral density (BMD), is associated with stress fractures and athletes aged 16-17 years are most susceptible. PURPOSE To examine whether the Triad increases the risk of stress fractures, athletes were assigned to a "teenage" group and a "20s" group. METHODS This prospective study enrolled 390 elite female athletes and was conducted from 2012 to 2016 at Japan Institute of Sports Sciences. Blood concentrations of various hormones were examined, and BMD was measured at the lumbar spine and throughout the whole body using dual-energy X-ray absorptiometry. LEA was defined as body weight ≤85% of the ideal body weight for teenage athletes, or BMI ≤17.5 for athletes in their 20s. Low BMD was defined as a BMD Z-score of <-1.0 in the lumbar spine and the whole body. RESULTS Among 390 athletes enrolled, 36 developed new stress fractures within 3 months of registration. The risk for stress fractures due to the Triad in teenage athletes was higher than for athletes in their 20s. In teenage female athletes, secondary amenorrhea, low BMD for the whole body, and a low ratio of actual body weight to ideal body weight increased the risk for stress fractures by 12.9 times, 4.5 times, and 1.1 times, respectively. CONCLUSION To prevent stress fractures in female athletes with the Triad, age of athletes should be taken into consideration.
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Affiliation(s)
- Sayaka Nose-Ogura
- Department of Obstetrics and Gynecology, University of Tokyo, Tokyo, Japan.,Sports Medical Center, Japan Institute of Sports Sciences, Tokyo, Japan.,Department of Obstetrics and Gynecology, University of Toyama, Toyama, Japan
| | - Osamu Yoshino
- Department of Obstetrics and Gynecology, University of Toyama, Toyama, Japan.,Department of Obstetrics and Gynecology, Kitasato University School of Medicine, Kanagawa, Japan
| | - Michiko Dohi
- Sports Medical Center, Japan Institute of Sports Sciences, Tokyo, Japan
| | - Mika Kigawa
- Faculty of Health and Social Services, Kanagawa University of Human Services, Kanagawa, Japan
| | - Miyuki Harada
- Department of Obstetrics and Gynecology, University of Tokyo, Tokyo, Japan
| | - Osamu Hiraike
- Department of Obstetrics and Gynecology, University of Tokyo, Tokyo, Japan
| | - Takashi Onda
- Department of Obstetrics and Gynecology, Kitasato University School of Medicine, Kanagawa, Japan
| | - Yutaka Osuga
- Department of Obstetrics and Gynecology, University of Tokyo, Tokyo, Japan
| | - Tomoyuki Fujii
- Department of Obstetrics and Gynecology, University of Tokyo, Tokyo, Japan
| | - Shigeru Saito
- Department of Obstetrics and Gynecology, University of Toyama, Toyama, Japan
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Holtzman B, Ackerman KE. Measurement, Determinants, and Implications of Energy Intake in Athletes. Nutrients 2019; 11:E665. [PMID: 30893893 PMCID: PMC6472042 DOI: 10.3390/nu11030665] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 03/09/2019] [Accepted: 03/15/2019] [Indexed: 12/28/2022] Open
Abstract
Appropriate energy intake is important for the health and performance of athletes. When an athlete's energy intake is not concordant with energy expenditure, short- and long-term performance can be compromised and negative health effects may arise. The energy intake patterns of athletes are subject to numerous effectors, including exercise response, time, and availability of food. To assess different determinants of energy intake in athletes, we reviewed recent literature regarding the response of appetite-regulating hormones to exercise, appetite perceptions following exercise, chronic exercise-induced adaptations regarding appetite, and social factors regarding energy intake. Additionally, we discussed consequences of aberrant energy intake. The purpose of this review is to clarify understanding about energy intake in athletes and provide insights into methods toward maintaining proper energy intake.
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Affiliation(s)
- Bryan Holtzman
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
- Female Athlete Program, Division of Sports Medicine and Endocrinology, Boston Children's Hospital, Boston, MA 02115, USA.
| | - Kathryn E Ackerman
- Female Athlete Program, Division of Sports Medicine and Endocrinology, Boston Children's Hospital, Boston, MA 02115, USA.
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, MA 02114, USA.
- Harvard Medical School, Boston, MA 02115, USA.
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Evidence of the Exercise-Hypogonadal Male Condition at the 2011 Kona Ironman World Championships. Int J Sports Physiol Perform 2019; 14:170-175. [DOI: 10.1123/ijspp.2017-0476] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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30
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Black K, Slater J, Brown RC, Cooke R. Low Energy Availability, Plasma Lipids, and Hormonal Profiles of Recreational Athletes. J Strength Cond Res 2019; 32:2816-2824. [PMID: 29624522 DOI: 10.1519/jsc.0000000000002540] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
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.
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Affiliation(s)
- Katherine Black
- Department of Human Nutrition, University of Otago, Dunedin, New Zealand
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Slater J, Brown R, McLay-Cooke R, Black K. Low Energy Availability in Exercising Women: Historical Perspectives and Future Directions. Sports Med 2018; 47:207-220. [PMID: 27430502 DOI: 10.1007/s40279-016-0583-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Research on the health of female athletes has developed substantially over the past 50 years. This review aims to provide an overview of this research and identify directions for future work. While early cross-sectional studies focused primarily on menstruation, research has progressed to now encompass hormonal changes, bone health and lipid profiles. The seminal work of Loucks and colleagues distinguished that these health concerns were due to low energy availability (LEA) rather than exercise alone. LEA occurs when the body has insufficient energy available to meet the needs of training and normal physiological functioning. While there appears to be agreement that LEA is the underlying cause of this syndrome, controversy regarding terminology has emerged. Originally coined the female athlete triad (Triad), some researchers are now advocating the use of the term relative energy deficiency in sport (RED-S). This group argues that the term Triad excludes male athletes who also have the potential to experience LEA and its associated negative impact on health and performance. At present, implications of LEA among male athletes are poorly understood and should form the basis of future research. Other directions for future research include determination of the prevalence and long-term risks of LEA in junior and developmental athletes, and the development of standardised tools to diagnose LEA. These tools are required to aid comparisons between studies and to develop treatment strategies to attenuate the long-term health consequences of LEA. Continued advances in knowledge on LEA and its associated health consequences will aid development of more effective prevention, early detection and treatment strategies.
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Affiliation(s)
- Joanne Slater
- Department of Human Nutrition, University of Otago, PO Box 56, Dunedin, New Zealand
| | - Rachel Brown
- Department of Human Nutrition, University of Otago, PO Box 56, Dunedin, New Zealand
| | - Rebecca McLay-Cooke
- Department of Human Nutrition, University of Otago, PO Box 56, Dunedin, New Zealand
| | - Katherine Black
- Department of Human Nutrition, University of Otago, PO Box 56, Dunedin, New Zealand.
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International Olympic Committee (IOC) Consensus Statement on Relative Energy Deficiency in Sport (RED-S): 2018 Update. Int J Sport Nutr Exerc Metab 2018; 28:316-331. [PMID: 29771168 DOI: 10.1123/ijsnem.2018-0136] [Citation(s) in RCA: 195] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Mountjoy M, Sundgot-Borgen JK, Burke LM, Ackerman KE, Blauwet C, Constantini N, Lebrun C, Lundy B, Melin AK, Meyer NL, Sherman RT, Tenforde AS, Klungland Torstveit M, Budgett R. IOC consensus statement on relative energy deficiency in sport (RED-S): 2018 update. Br J Sports Med 2018; 52:687-697. [DOI: 10.1136/bjsports-2018-099193] [Citation(s) in RCA: 345] [Impact Index Per Article: 57.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/17/2018] [Indexed: 01/20/2023]
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Negative Consequences of Low Energy Availability in Natural Male Bodybuilding: A Review. Int J Sport Nutr Exerc Metab 2018; 28:385-402. [PMID: 28530498 DOI: 10.1123/ijsnem.2016-0332] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Energy availability (EA) is a scientific concept describing how much energy is available for basic metabolic functions such as reproduction, immunity, and skeletal homeostasis. Carefully controlled studies on women have shown pathological effects of EA < 30 kcal/kg fat-free mass (FFM), and this state has been labeled low EA (LEA). Bodybuilding is a sport in which athletes compete to show muscular definition, symmetry, and low body fat (BF). The process of contest preparation in bodybuilding includes months of underfeeding, thus increasing the risk of LEA and its negative health consequences. As no well-controlled studies have been conducted in natural male bodybuilders on effects of LEA, the aim of this review was to summarize what can be extrapolated from previous relevant research findings in which EA can be calculated. The reviewed literature indicates that a prolonged EA < 25 kcal/kg FFM results in muscle loss, hormonal imbalances, psychological problems, and negatively affects the cardiovascular system when approaching the lower limits of BF (∼4%-5%) among males. Case studies on natural male bodybuilders who prepare for contest show muscle loss (>40% of total weight loss) with EA < 20 kcal/kg FFM, and in the study with the lowest observed BF (∼4 kg), major mood disturbance and hormonal imbalances co-occurred. Studies also underline the problem of BF overshoot during refeeding after extremes of LEA among males. A more tempered approach (EA > 25 kcal/kg FFM) might result in less muscle loss among natural male bodybuilders who prepare for contest, but more research is needed.
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De Souza MJ, Koltun KJ, Etter CV, Southmayd EA. Current Status of the Female Athlete Triad: Update and Future Directions. Curr Osteoporos Rep 2017; 15:577-587. [PMID: 29027102 DOI: 10.1007/s11914-017-0412-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW This review provides an update on the primary clinical sequelae of the Female Athlete Triad. RECENT FINDINGS Scientific advancements have contributed to improve understanding of Triad-related conditions, including leptin's role as a potential neuroendocrine link between energy status and reproductive function. Use of finite element analysis of HRpQCT imaging has provided a more accurate assessment of bone geometry and bone strength and may be clinically relevant. New perspectives aimed at developing and implementing a multi-disciplinary, personalized approach in the prevention and early treatment of triad-related symptoms are provided. The Female Athlete Triad is a multi-dimensional condition that affects active women across the lifespan. Energy availability impacts reproductive function and bone with implications for health and performance. Understanding the contributions of each individual component as well as their interconnected effects is necessary for progression and expansion of the Triad literature.
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Affiliation(s)
- Mary Jane De Souza
- Department of Kinesiology and Physiology Women's Health and Exercise Lab, 104 Noll Laboratory, College of Health and Human Development, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Kristen J Koltun
- Department of Kinesiology Women's Health and Exercise Lab, College of Health and Human Development, The Pennsylvania State University, University Park, USA
| | - Clara V Etter
- Department of Kinesiology Women's Health and Exercise Lab, College of Health and Human Development, The Pennsylvania State University, University Park, USA
| | - Emily A Southmayd
- Department of Kinesiology Women's Health and Exercise Lab, College of Health and Human Development, The Pennsylvania State University, University Park, USA
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Carl RL, Johnson MD, Martin TJ, LaBella CR, Brooks MA, Diamond A, Hennrikus W, LaBotz M, Logan K, Loud KJ, Moffatt KA, Nemeth B, Pengel B, Peterson A. Promotion of Healthy Weight-Control Practices in Young Athletes. Pediatrics 2017; 140:peds.2017-1871. [PMID: 28827381 DOI: 10.1542/peds.2017-1871] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Children and adolescents may participate in sports that favor a particular body type. Some sports, such as gymnastics, dance, and distance running, emphasize a slim or lean physique for aesthetic or performance reasons. Participants in weight-class sports, such as wrestling and martial arts, may attempt weight loss so they can compete at a lower weight class. Other sports, such as football and bodybuilding, highlight a muscular physique; young athletes engaged in these sports may desire to gain weight and muscle mass. This clinical report describes unhealthy methods of weight loss and gain as well as policies and approaches used to curb these practices. The report also reviews healthy strategies for weight loss and weight gain and provides recommendations for pediatricians on how to promote healthy weight control in young athletes.
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Affiliation(s)
- Rebecca L. Carl
- Institute for Sports Medicine, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, Illinois
| | - Miriam D. Johnson
- Department of Pediatrics, University of Washington, Seattle, Washington
| | - Thomas J. Martin
- Department of Pediatrics, Geisinger Commonwealth School of Medicine, Scranton, Pennsylvania
- Department of Pediatrics, Milton S. Hershey College of Medicine, Pennsylvania State University, Hershey, Pennsylvania; and
- Central Pennsylvania Clinic for Special Children and Adults, Belleville, Pennsylvania
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Papageorgiou M, Dolan E, Elliott-Sale KJ, Sale C. Reduced energy availability: implications for bone health in physically active populations. Eur J Nutr 2017; 57:847-859. [PMID: 28721562 PMCID: PMC5861178 DOI: 10.1007/s00394-017-1498-8] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 07/03/2017] [Indexed: 01/17/2023]
Abstract
Purpose The present review critically evaluates existing literature on the effects of short- and long-term low energy availability (EA) on bone metabolism and health in physically active individuals. Methods We reviewed the literature on the short-term effects of low EA on markers of bone metabolism and the long-term effects of low EA on outcomes relating to bone health (bone mass, microarchitecture and strength, bone metabolic markers and stress fracture injury risk) in physically active individuals. Results Available evidence indicates that short-term low EA may increase markers of bone resorption and decrease markers of bone formation in physically active women. Bone metabolic marker responses to low EA are less well known in physically active men. Cross-sectional studies investigating the effects of long-term low EA suggest that physically active individuals who have low EA present with lower bone mass, altered bone metabolism (favouring bone resorption), reduced bone strength and increased risk for stress fracture injuries. Conclusions Reduced EA has a negative influence on bone in both the short- and long-term, and every effort should be made to reduce its occurrence in physically active individuals. Future interventions are needed to explore the effects of long-term reduced EA on bone health outcomes, while short-term low EA studies are also required to give insight into the pathophysiology of bone alterations.
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Affiliation(s)
- Maria Papageorgiou
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS UK
| | - Eimear Dolan
- Applied Physiology and Nutrition Research Group, University of Sao Paulo, São Paulo, Brazil
| | - Kirsty J. Elliott-Sale
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS UK
| | - Craig Sale
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS UK
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Female Athlete Triad: Future Directions for Energy Availability and Eating Disorder Research and Practice. Clin Sports Med 2017; 36:671-686. [PMID: 28886821 DOI: 10.1016/j.csm.2017.05.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Despite more than 3 decades of research on the Female Athlete Triad, research gaps remain. Although low energy availability (EA) is the key etiologic factor in the Triad and the pathways to low EA are varied, its effects can be modified by several factors. Accurate screening, diagnosis, and treatment of disordered eating are a challenge; however, recent techniques combined with novel educational and behavior interventions prove promising. Recently published practice-based guidelines have helped to translate Triad science and should improve as they are refined. This article identifies the current state of research and distinguishes areas that require further investigation.
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Brown KA, Dewoolkar AV, Baker N, Dodich C. The female athlete triad: special considerations for adolescent female athletes. Transl Pediatr 2017; 6:144-149. [PMID: 28795004 PMCID: PMC5532188 DOI: 10.21037/tp.2017.04.04] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
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.
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Affiliation(s)
- Kelly A Brown
- Western Michigan University Homer Stryker MD School of Medicine, Kalamazoo, Michigan, USA
| | - Aditya V Dewoolkar
- Louisiana State University HSC, Children's Hospital of New Orleans, New Orleans, Louisiana, USA
| | - Nicole Baker
- Western Michigan University Homer Stryker MD School of Medicine, Kalamazoo, Michigan, USA
| | - Colleen Dodich
- Western Michigan University Homer Stryker MD School of Medicine, Kalamazoo, Michigan, USA
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Hooper DR, Kraemer WJ, Saenz C, Schill KE, Focht BC, Volek JS, Maresh CM. The presence of symptoms of testosterone deficiency in the exercise-hypogonadal male condition and the role of nutrition. Eur J Appl Physiol 2017; 117:1349-1357. [PMID: 28470410 DOI: 10.1007/s00421-017-3623-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 04/24/2017] [Indexed: 10/19/2022]
Abstract
PURPOSE High volumes of aerobic exercise have been associated with reduced testosterone (T), known as the exercise-hypogonadal male condition (EHMC). Although the presence of low T has been identified, few studies have assessed the presence of androgen-deficient symptoms. The purpose of this investigation is to assess men exhibiting EHMC and evaluate their hypothalamic-pituitary-gonadal axis, the presence of hypogonadal symptoms, and also investigate a possible contribution of inadequate nutrition to the condition. METHODS A cross-sectional design compared 9 long-distance runners exhibiting EHMC to 8 non-active controls. Comparisons included serum T, luteinizing hormone (LH), follicle-stimulating hormone, and cortisol, the Aging Male Symptoms (AMS) questionnaire score, bone mineral density (BMD), and a food frequency questionnaire. RESULTS Mean T was significantly reduced in the EHMC group (EHMC 9.2 nmol L-1 vs. CONT 16.2 nmol L-1). The EHMC group demonstrated significantly higher AMS scores (EHMC 27.1 ± 7.3 vs. CONT 19.7 ± 2.5). There were no differences in bone density, although 3 cases of osteopenia were noted for EHMC in the lumbar spine, 1 in the right femur, and 1 in the radius. Energy availability was significantly reduced in EHMC (EHMC 27.2 ± 12.7 vs. CONT 45.4 ± 18.2 kcal d FFM-1). CONCLUSIONS Men exhibiting EHMC do appear to present with symptoms associated with androgen deficiency. For the most part, these symptoms are limited to those reported on the AMS questionnaire, although there are also some cases of clinically low BMD. It is possible that inadequate energy intake is contributing to this condition.
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Affiliation(s)
- David R Hooper
- Department of Health Sciences, Armstrong State University, Savannah, GA, USA.,Department of Human Sciences, The Ohio State University, A054 PAES Building, 305 Annie and John Glenn Avenue, Columbus, OH, 43210, USA
| | - William J Kraemer
- Department of Human Sciences, The Ohio State University, A054 PAES Building, 305 Annie and John Glenn Avenue, Columbus, OH, 43210, USA.
| | - Catherine Saenz
- Department of Human Sciences, The Ohio State University, A054 PAES Building, 305 Annie and John Glenn Avenue, Columbus, OH, 43210, USA
| | - Kevin E Schill
- Department of Human Sciences, The Ohio State University, A054 PAES Building, 305 Annie and John Glenn Avenue, Columbus, OH, 43210, USA
| | - Brian C Focht
- Department of Human Sciences, The Ohio State University, A054 PAES Building, 305 Annie and John Glenn Avenue, Columbus, OH, 43210, USA
| | - Jeff S Volek
- Department of Human Sciences, The Ohio State University, A054 PAES Building, 305 Annie and John Glenn Avenue, Columbus, OH, 43210, USA
| | - Carl M Maresh
- Department of Human Sciences, The Ohio State University, A054 PAES Building, 305 Annie and John Glenn Avenue, Columbus, OH, 43210, USA
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Duignan M, O'Connor N. Female athlete triad: At breaking point. Int Emerg Nurs 2017; 34:51-54. [PMID: 28442226 DOI: 10.1016/j.ienj.2017.03.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 03/26/2017] [Indexed: 11/20/2022]
Affiliation(s)
| | - Niall O'Connor
- Our Lady's Hospital, Navan, Ireland; Our Lady of Lourdes Hospital, Drogheda, Ireland
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Female Athlete Triad or Relative Energy Deficiency in Sports (RED-S): Is There a Difference? J Acad Nutr Diet 2016; 116:744. [PMID: 27017180 DOI: 10.1016/j.jand.2016.01.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Indexed: 11/20/2022]
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Mountjoy M, Sundgot-Borgen J, Burke L, Carter S, Constantini N, Lebrun C, Meyer N, Sherman R, Steffen K, Budgett R, Ljungqvist A. Authors’ 2015 additions to the IOC consensus statement: Relative Energy Deficiency in Sport (RED-S). Br J Sports Med 2015; 49:417-20. [DOI: 10.1136/bjsports-2014-094371] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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