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1.
J Int Soc Sports Nutr ; 20(1): 2204066, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37221858

RESUMEN

Based on a comprehensive review and critical analysis of the literature regarding the nutritional concerns of female athletes, conducted by experts in the field and selected members of the International Society of Sports Nutrition (ISSN), the following conclusions represent the official Position of the Society: 1. Female athletes have unique and unpredictable hormone profiles, which influence their physiology and nutritional needs across their lifespan. To understand how perturbations in these hormones affect the individual, we recommend that female athletes of reproductive age should track their hormonal status (natural, hormone driven) against training and recovery to determine their individual patterns and needs and peri and post-menopausal athletes should track against training and recovery metrics to determine the individuals' unique patterns. 2. The primary nutritional consideration for all athletes, and in particular, female athletes, should be achieving adequate energy intake to meet their energy requirements and to achieve an optimal energy availability (EA); with a focus on the timing of meals in relation to exercise to improve training adaptations, performance, and athlete health. 3. Significant sex differences and sex hormone influences on carbohydrate and lipid metabolism are apparent, therefore we recommend first ensuring athletes meet their carbohydrate needs across all phases of the menstrual cycle. Secondly, tailoring carbohydrate intake to hormonal status with an emphasis on greater carbohydrate intake and availability during the active pill weeks of oral contraceptive users and during the luteal phase of the menstrual cycle where there is a greater effect of sex hormone suppression on gluconogenesis output during exercise. 4. Based upon the limited research available, we recommend that pre-menopausal, eumenorrheic, and oral contraceptives using female athletes should aim to consume a source of high-quality protein as close to beginning and/or after completion of exercise as possible to reduce exercise-induced amino acid oxidative losses and initiate muscle protein remodeling and repair at a dose of 0.32-0.38 g·kg-1. For eumenorrheic women, ingestion during the luteal phase should aim for the upper end of the range due to the catabolic actions of progesterone and greater need for amino acids. 5. Close to the beginning and/or after completion of exercise, peri- and post-menopausal athletes should aim for a bolus of high EAA-containing (~10 g) intact protein sources or supplements to overcome anabolic resistance. 6. Daily protein intake should fall within the mid- to upper ranges of current sport nutrition guidelines (1.4-2.2 g·kg-1·day-1) for women at all stages of menstrual function (pre-, peri-, post-menopausal, and contraceptive users) with protein doses evenly distributed, every 3-4 h, across the day. Eumenorrheic athletes in the luteal phase and peri/post-menopausal athletes, regardless of sport, should aim for the upper end of the range. 7. Female sex hormones affect fluid dynamics and electrolyte handling. A greater predisposition to hyponatremia occurs in times of elevated progesterone, and in menopausal women, who are slower to excrete water. Additionally, females have less absolute and relative fluid available to lose via sweating than males, making the physiological consequences of fluid loss more severe, particularly in the luteal phase. 8. Evidence for sex-specific supplementation is lacking due to the paucity of female-specific research and any differential effects in females. Caffeine, iron, and creatine have the most evidence for use in females. Both iron and creatine are highly efficacious for female athletes. Creatine supplementation of 3 to 5 g per day is recommended for the mechanistic support of creatine supplementation with regard to muscle protein kinetics, growth factors, satellite cells, myogenic transcription factors, glycogen and calcium regulation, oxidative stress, and inflammation. Post-menopausal females benefit from bone health, mental health, and skeletal muscle size and function when consuming higher doses of creatine (0.3 g·kg-1·d-1). 9. To foster and promote high-quality research investigations involving female athletes, researchers are first encouraged to stop excluding females unless the primary endpoints are directly influenced by sex-specific mechanisms. In all investigative scenarios, researchers across the globe are encouraged to inquire and report upon more detailed information surrounding the athlete's hormonal status, including menstrual status (days since menses, length of period, duration of cycle, etc.) and/or hormonal contraceptive details and/or menopausal status.


Asunto(s)
Creatina , Deportes , Femenino , Humanos , Masculino , Progesterona , Atletas , Aminoácidos
2.
J Int Soc Sports Nutr ; 20(1): 2204071, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37096381

RESUMEN

Creatine supplementation is an effective ergogenic aid to augment resistance training and improve intense, short duration, intermittent performance. The effects on endurance performance are less known. The purpose of this brief narrative review is to discuss the potential mechanisms of how creatine can affect endurance performance, defined as large muscle mass activities that are cyclical in nature and are >~3 min in duration, and to highlight specific nuances within the literature. Mechanistically, creatine supplementation elevates skeletal muscle phosphocreatine (PCr) stores facilitating a greater capacity to rapidly resynthesize ATP and buffer hydrogen ion accumulation. When co-ingested with carbohydrates, creatine enhances glycogen resynthesis and content, an important fuel to support high-intensity aerobic exercise. In addition, creatine lowers inflammation and oxidative stress and has the potential to increase mitochondrial biogenesis. In contrast, creatine supplementation increases body mass, which may offset the potential positive effects, particularly in weight-bearing activities. Overall, creatine supplementation increases time to exhaustion during high-intensity endurance activities, likely due to increasing anaerobic work capacity. In terms of time trial performances, results are mixed; however, creatine supplementation appears to be more effective at improving performances that require multiple surges in intensity and/or during end spurts, which are often key race-defining moments. Given creatines ability to enhance anaerobic work capacity and performance through repeated surges in intensity, creatine supplementation may be beneficial for sports, such as cross-country skiing, mountain biking, cycling, triathlon, and for short-duration events where end-spurts are critical for performance, such as rowing, kayaking, and track cycling.


Asunto(s)
Creatina , Resistencia Física , Humanos , Resistencia Física/fisiología , Suplementos Dietéticos , Fosfocreatina , Músculo Esquelético , Glucógeno
4.
J Diet Suppl ; 20(4): 621-630, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35583055

RESUMEN

The purpose of this investigation was to determine the effects of supplementing with 100 mg daily of 5-Hydroxytryptophan (5-HTP) on indices of body composition in exercise-trained men and women. Sixty-one subjects volunteered for this investigation. Forty-eight subjects were randomized into a treatment (n = 31, 12 male/19 female; 100 mg 5-HTP daily; CLEANMOOD™) or a placebo (n = 17, six male/11 female; maltodextrin). Body composition was assessed pre- and post-treatment after eight weeks via a multi-frequency bioelectrical impedance device (InBody® 270). Subjects were instructed to not change their training or eating habits; moreover, they were instructed to track their diet ∼2-3 days per week using a mobile app (MyFitnessPal). There were no changes in food intake (i.e. total energy intake or grams of macronutrients) between or within groups. Lean body mass, total body water, and % body fat did not change significantly in either group. Fat mass decreased significantly post versus pre in the 5-HTP group (p = 0.02) but did not change in the placebo group (p = 0.58). Moreover, changes in fat mass were significantly different between the 5-HTP and placebo group (p = 0.048). Based on the limited data from this investigation, daily supplementation with 100 mg of 5-HTP may affect body composition.


Asunto(s)
5-Hidroxitriptófano , Composición Corporal , Humanos , Masculino , Femenino , 5-Hidroxitriptófano/farmacología , Ingestión de Energía , Tejido Adiposo , Dieta
5.
Plast Reconstr Surg ; 143(4): 1051-1060, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30921120

RESUMEN

BACKGROUND: The ideal body is characterized by a muscular physique and defined anterior abdominal wall. Despite diet and exercise, many are unable to achieve this desired result. Liposuction with abdominal etching is used to achieve high-definition abdominal aesthetics. The etching technique is performed with liposuction in a superficial plane, to create indentures consistent with "six-pack abs," or definition of vertical abdominal lines. METHODS: The authors' abdominal etching preoperative markings, surgical technique, and postoperative care are discussed. The surgeons' experience with abdominal etching in 50 consecutive patients is reviewed, including rate of complications and patient satisfaction. RESULTS: The average patient age was 36.4 years. We had an almost equal number of men (n = 26) and women (n = 24), with an average body mass index of 26.7 kg/m. The average blood loss was 275 ml, the average tumescence was 6 liters, and the average lipoaspirate was 5 liters. There were no major complications such as fat embolus, deep venous thrombosis, or intraabdominal injury. The most common minor postoperative complications were contour irregularities (12 percent), seromas (10 percent), and hyperpigmentation (2 percent). The majority of patients were satisfied (98 percent). The average length of postoperative follow-up was 27 months. CONCLUSIONS: Abdominal etching is a safe and effective method of creating a defined anterior abdominal wall for patients who desire the muscular definition of vertical abdominal lines. Almost all of our patients reviewed were satisfied with this procedure, maintained long-term results, and had an acceptable rate of complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.


Asunto(s)
Músculos Abdominales/cirugía , Pared Abdominal/cirugía , Lipectomía/métodos , Grasa Subcutánea Abdominal/cirugía , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
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