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1.
Med Sci Sports Exerc ; 53(4): 673-683, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33105389

RESUMO

PURPOSE: This study aimed to evaluate the effects of low energy availability (EA) on health and performance indices associated with the Male Athlete Triad and Relative Energy Deficiency in Sport (RED-S) models. METHODS: Over an 8-wk period, a male combat sport athlete adhered to a phased body mass (BM) loss plan consisting of 7-wk energy intake (EI) equating to resting metabolic rate (RMR) (1700 kcal·d-1) (phase 1), 5 d of reduced EI (1200-300 kcal·d-1) before weigh-in (phase 2), and 1 wk of ad libitum EI postcompetition (phase 3). EA fluctuated day by day because of variations in exercise energy expenditure. Regular assessments of body composition, RMR, cardiac function, cardiorespiratory capacity, strength and power, psychological state and blood clinical chemistry for endocrine, bone turnover, hydration, electrolyte, renal, liver, and lipid profiles were performed. RESULTS: BM was reduced over the 8-wk period by 13.5% (72.5 to 62.7 kg). No consequences of Male Athlete Triad or RED-S were evident during phase 1, where mean daily EA equated to 20 kcal·kg·fat free mass (FFM)-1·d-1 (range, 7 to 31 kcal·kg FFM-1·d-1) and BM and fat mass (FM) losses were 6.5 and 4.4 kg, respectively. However, consequences did present in phase 2 when mean daily EA was consistently <10 kcal·kg FFM-1·d-1, as evidenced by alterations to endocrine hormones (e.g., testosterone <5 nmol.L-1) and reduced RMR (-257 kcal·d-1). CONCLUSION: Data demonstrate that 7 wk of daily fluctuations in EA equating to a mean value of 20 kcal·kg FFM-1·d-1 permits reductions of BM and FM without perturbations to physiological systems associated with the Male Athlete Triad and RED-S. By contrast, a subsequent period of five consecutive days of EA <10 kcal·kg FFM-1·d-1 induced consequences of Male Athlete Triad and RED-S.


Assuntos
Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Artes Marciais/fisiologia , Artes Marciais/psicologia , Atletas , Metabolismo Basal , Composição Corporal/fisiologia , Índice de Massa Corporal , Aptidão Cardiorrespiratória/fisiologia , Frequência Cardíaca , Humanos , Masculino , Força Muscular/fisiologia , Contração Miocárdica , Deficiência Energética Relativa no Esporte/sangue , Deficiência Energética Relativa no Esporte/fisiopatologia , Volume Sistólico , Testosterona/sangue , Fatores de Tempo , Redução de Peso/fisiologia , Adulto Jovem
2.
Laeknabladid ; 106(9): 406-413, 2020 Sep.
Artigo em Islandês | MEDLINE | ID: mdl-32902400

RESUMO

Fulfilling individual energy and nutrient requirements is of great importance for athletes to support overall health and well-being, training adaptation, recovery and injury prevention. Energy availability is the amount of energy left over and available for bodily functions after the energy expended for training is subtracted from the energy taken in from food. The syndrome of Relative Energy Deficiency in Sport (RED-s) refers to the multifactorial health and performance consequences of low energy availability. Potential physiological implications of RED-s include impaired metabolic rate, hormonal disruptions, menstrual dysfunction, reduced bone health, immunity, protein synthesis, and cardiovascular health. These can have short and long term consequences on health and sport performance. Causes of RED-s range from unintentional (e.g. lack of awareness or difficulties with meeting high energy requirements) to more intentional behaviors and further to clinical eating disorders. RED-s prevalence appears to differ between sports and sport disciplines, with highest risk in endurance, aesthetic and weight-class sports. This article summarizes current knowledge of RED-s implications for health and performance, and highlights the importance of early diagnosis and screening. Research on RED-s in Icelandic athletes is warranted as it could support development of national guidelines, prevention and treatment protocols.


Assuntos
Atletas , Dieta , Ingestão de Energia , Metabolismo Energético , Valor Nutritivo , Resistência Física , Deficiência Energética Relativa no Esporte , Dieta/efeitos adversos , Humanos , Necessidades Nutricionais , Estado Nutricional , Prevalência , Prognóstico , Deficiência Energética Relativa no Esporte/diagnóstico , Deficiência Energética Relativa no Esporte/epidemiologia , Deficiência Energética Relativa no Esporte/fisiopatologia , Deficiência Energética Relativa no Esporte/terapia , Medição de Risco , Fatores de Risco
3.
Int J Sport Nutr Exerc Metab ; 30(1): 14-24, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31887723

RESUMO

Energy deficiency in exercising women can lead to physiological consequences. No gold standard exists to accurately estimate energy deficiency, but measured-to-predicted resting metabolic rate (RMR) ratio has been used to categorize women as energy deficient. The purpose of the study was to (a) evaluate the accuracy of RMR prediction methods, (b) determine the relationships with physiological consequences of energy deficiency, and (c) evaluate ratio thresholds in a cross-sectional comparison of ovulatory, amenorrheic, or subclinical menstrual disturbances in exercising women (n = 217). Dual-energy X-ray absorptiometry (DXA) and indirect calorimetry provided data on anthropometrics and energy expenditure. Harris-Benedict, DXA, and Cunningham (1980 and 1991) equations were used to estimate RMR and RMR ratio. Group differences were assessed (analysis of variance and Kruskal-Wallis tests); logistic regression and Spearman correlations related ratios with consequences of energy deficiency (i.e., low total triiodothyronine; TT3). Sensitivity and specificity calculations evaluated ratio thresholds. Amenorrheic women had lower RMR (p < .05), DXA ratio (p < .01), Cunningham1980 (p < .05) and Cunningham1991 (p < .05) ratio, and TT3 (p < .01) compared with the ovulatory group. Each prediction equation overestimated measured RMR (p < .001), but predicted (p < .001) and positively correlated with TT3 (r = .329-.453). A 0.90 ratio threshold yielded highest sensitivity for Cunningham1980 (0.90) and Harris-Benedict (0.87) methods, but a higher ratio threshold was best for DXA (0.94) and Cunningham1991 (0.92) methods to yield a sensitivity of 0.80. In conclusion, each ratio predicted and correlated with TT3, supporting the use of RMR ratio as an alternative assessment of energetic status in exercising women. However, a 0.90 ratio cutoff is not universal across RMR estimation methods.


Assuntos
Metabolismo Basal , Exercício Físico/fisiologia , Deficiência Energética Relativa no Esporte/fisiopatologia , Absorciometria de Fóton , Adolescente , Adulto , Amenorreia/fisiopatologia , Amenorreia/psicologia , Biomarcadores/sangue , Índice de Massa Corporal , Calorimetria Indireta , Estudos Transversais , Metabolismo Energético , Exercício Físico/psicologia , Feminino , Humanos , Distúrbios Menstruais/fisiopatologia , Distúrbios Menstruais/psicologia , Ovulação , Tri-Iodotironina/sangue , Adulto Jovem
5.
Sports Med ; 49(Suppl 2): 125-137, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31696452

RESUMO

The Female Athlete Triad represents three interrelated conditions of (i) low energy availability (energy deficiency), presenting with or without disordered eating, (ii) menstrual dysfunction, and (iii) poor bone health, each of which can exist along a continuum of severity ranging from mild and moderate subclinical health concerns to severe clinical outcomes, including eating disorders, amenorrhea, and osteoporosis. This review provides a brief overview of the Female Athlete Triad, including updating the current thinking regarding energy availability and how it relates to reproductive function, and sets the stage for an initial working model of a similar syndrome in males that will be based on currently available evidence and will later be defined and referred to as a Male Athlete Triad by the newly re-named Female and Male Athlete Triad Coalition. A primary focus of this paper will be on the physiology of each Triad model with an emphasis on low energy availability and its role in reproductive function, with a brief introduction on its effects on bone health in men. From the data reviewed, (i) a specific threshold of energy availability below which menstrual disturbances are induced is not supported; (ii) it appears that the energetic, reproductive, and bone systems in men are more resilient to the effects of low energy availability compared to those of women, requiring more severe energetic perturbations before alterations are observed; and (iii) it appears that recovery of the hypothalamic pituitary gonadal axis can be observed more quickly in men than in women.


Assuntos
Metabolismo Energético , Síndrome da Tríade da Mulher Atleta/fisiopatologia , Deficiência Energética Relativa no Esporte/fisiopatologia , Amenorreia/etiologia , Osso e Ossos/fisiopatologia , Comportamento Alimentar , Transtornos da Alimentação e da Ingestão de Alimentos , Feminino , Humanos , Hipogonadismo/etiologia , Sistema Hipotálamo-Hipofisário , Masculino , Menstruação , Osteoporose/etiologia
6.
Int J Sport Nutr Exerc Metab ; 29(6): 682-689, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31141414

RESUMO

Physique competitions are events in which aesthetic appearance and posing ability are valued above physical performance. Female physique athletes are required to possess high lean body mass and extremely low fat mass in competition. As such, extended periods of reduced energy intake and intensive training regimens are used with acute weight loss practices at the end of the precompetition phase. This represents an increased risk for chronic low energy availability and associated symptoms of relative energy deficiency in sport, compromising both psychological and physiological health. Available literature suggests that a large proportion of female physique athletes report menstrual irregularities (e.g., amenorrhea and oligomenorrhea), which are unlikely to normalize immediately postcompetition. Furthermore, the tendency to reduce intakes of numerous essential micronutrients is prominent among those using restrictive eating patterns. Following competition, reduced resting metabolic rate, and hyperphagia, is also a concern for these female athletes, which can result in frequent weight cycling, distorted body image, and disordered eating/eating disorders. Overall, female physique athletes are an understudied population, and the need for more robust studies to detect low energy availability and associated health effects is warranted. This narrative review aims to define the natural female physique athlete, explore some of the physiological and psychological implications of weight management practices experienced by female physique athletes, and propose future research directions.


Assuntos
Atletas/psicologia , Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Redução de Peso/fisiologia , Composição Corporal/fisiologia , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Humanos , Deficiência Energética Relativa no Esporte/fisiopatologia , Deficiência Energética Relativa no Esporte/psicologia
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