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1.
Am J Respir Cell Mol Biol ; 66(1): 38-52, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34343038

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive disease which leads to significant morbidity and mortality from respiratory failure. The two drugs currently approved for clinical use slow the rate of decline in lung function but have not been shown to halt disease progression or reverse established fibrosis. Thus, new therapeutic targets are needed. Endothelial injury and the resultant vascular permeability are critical components in the response to tissue injury and are present in patients with IPF. However, it remains unclear how vascular permeability affects lung repair and fibrosis following injury. Lipid mediators such as sphingosine-1-phosphate (S1P) are known to regulate multiple homeostatic processes in the lung including vascular permeability. We demonstrate that endothelial cell-(EC) specific deletion of the S1P receptor 1 (S1PR1) in mice (EC-S1pr1-/-) results in increased lung vascular permeability at baseline. Following a low-dose intratracheal bleomycin challenge, EC-S1pr1-/- mice had increased and persistent vascular permeability compared with wild-type mice, which was strongly correlated with the amount and localization of resulting pulmonary fibrosis. EC-S1pr1-/- mice also had increased immune cell infiltration and activation of the coagulation cascade within the lung. However, increased circulating S1P ligand in ApoM-overexpressing mice was insufficient to protect against bleomycin-induced pulmonary fibrosis. Overall, these data demonstrate that endothelial cell S1PR1 controls vascular permeability in the lung, is associated with changes in immune cell infiltration and extravascular coagulation, and modulates the fibrotic response to lung injury.


Assuntos
Permeabilidade Capilar , Células Endoteliais/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Receptores de Esfingosina-1-Fosfato/metabolismo , Animais , Bleomicina , Coagulação Sanguínea , Deleção de Genes , Fibrose Pulmonar Idiopática/sangue , Pulmão/irrigação sanguínea , Pulmão/patologia , Lisofosfolipídeos/sangue , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , RNA-Seq , Análise de Célula Única , Esfingosina/análogos & derivados , Esfingosina/sangue
2.
Int J Sport Nutr Exerc Metab ; 29(6): 671-681, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31034252

RESUMO

Hepcidin, a peptide hormone with an acknowledged evolutionary function in iron homeostasis, was discovered at the turn of the 21st century. Since then, the implications of increased hepcidin activity have been investigated as a potential advocate for the increased risk of iron deficiency in various health settings. Such implications are particularly relevant in the sporting community where peaks in hepcidin postexercise (∼3-6 hr) are suggested to reduce iron absorption and recycling, and contribute to the development of exercise-induced iron deficiency in athletes. Over the last decade, hepcidin research in sport has focused on acute and chronic hepcidin activity following single and repeated training blocks. This research has led to investigations examining possible methods to attenuate postexercise hepcidin expression through dietary interventions. The majority of macronutrient dietary interventions have focused on manipulating the carbohydrate content of the diet in an attempt to determine the health of athletes adopting the low-carbohydrate or ketogenic diets, a practice that is a growing trend among endurance athletes. During the process of these macronutrient dietary intervention studies, an observable coincidence of increased cumulative hepcidin activity to low energy availability has emerged. Therefore, this review aims to summarize the existing literature on nutritional interventions on hepcidin activity, thus, highlighting the link of hepcidin to energy availability, while also making a case for the use of hepcidin as an individualized biomarker for low energy availability in males and females.


Assuntos
Hepcidinas/sangue , Deficiência Energética Relativa no Esporte/metabolismo , Biomarcadores/sangue , Carboidratos da Dieta , Gorduras na Dieta , Humanos , Fatores de Risco
3.
J Sleep Res ; 27(4): e12634, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29160021

RESUMO

It is well documented that short sleep duration is associated with excess body weight and poor food intake in children. It has been suggested that sleep timing behaviour may also be an important predictor of weight and other related behaviours, independent of sleep duration; however, there is a lack of research investigating these relationships. The present study investigated sleep timing in association with diet and physical activity levels in 439 children aged 9-11 years old from New Zealand. Sleep and physical activity data were collected using accelerometry, and food choice using a short food-frequency questionnaire. Participants were classified into one of four sleep timing behaviour categories using the median split for sleep-onset and -offset times. Differences between sleep timing groups for weekly consumption frequency of selected food groups, dietary pattern scores and minutes of moderate-to-vigorous physical activity were examined. Children in the late sleep/late wake category had a lower 'Fruit & Vegetables' pattern score [mean difference (95% CI): -0.3 (-0.5, -0.1)], a lower consumption frequency of fruit and vegetables [mean weekly difference (95% CI): -2.9 (-4.9, -0.9)] and a higher consumption frequency of sweetened beverages [mean weekly difference (95% CI): 1.8 (0.2, 3.3)] compared with those in the early sleep/early wake category. Additionally, children in the late sleep/late wake category accumulated fewer minutes of moderate-to-vigorous physical activity per day compared with those in the early sleep/early wake category [mean difference (95% CI): -9.4 (-15.3, -3.5)]. These findings indicate that sleep timing, even after controlling for sleep duration, was associated with both food consumption and physical activity.


Assuntos
Acelerometria/métodos , Dieta/tendências , Ingestão de Alimentos/fisiologia , Exercício Físico/fisiologia , Sono/fisiologia , Bebidas , Peso Corporal/fisiologia , Criança , Estudos Transversais , Dieta/psicologia , Ingestão de Alimentos/psicologia , Exercício Físico/psicologia , Feminino , Frutas , Humanos , Masculino , Nova Zelândia/epidemiologia , Fatores de Tempo
4.
J Strength Cond Res ; 32(1): 19-26, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27820726

RESUMO

McIntosh, ND, Love, TD, Haszard, J, Osborne, H, and Black, KE. ß-hydroxy ß-methylbutyrate (HMB) supplementation effects on body mass and performance in elite male rugby union players. J Strength Cond Res 32(1): 19-26, 2018-Preseason is characterized by high training volumes with short recovery periods ß-hydroxy ß-methylbutyrate (HMB) has been postulated to assist with recovery. ß-hydroxy ß-methylbutyrate has been shown to improve strength and body composition among untrained groups; the benefits of HMB among trained populations are unclear because of the methodologies employed. This randomized control trail determined the effects of 11 weeks HMB supplementation on body mass and performance measures in 27 elite rugby players. ß-hydroxy ß-methylbutyrate group (n = 13), mean ± SD age 20.3 ± 1.2 years, body mass 99.6 ± 9.1 kg; placebo group (n = 14), age 21.9 ± 2.8 years body mass 99.4 ± 13.9 kg for placebo. During the supplementation period, body mass increased with HMB 0.57 ± 2.60 kg but decreased with placebo 1.39 ± 2.02 kg (p = 0.029). There were no significant differences in any of the 4 strength variables (p > 0.05). However, on the yo-yo intermittent recovery test (YoYo IR-1), the placebo group improved 4.0 ± 2.8 levels but HMB decreased 2.0 ± 3.0 levels (p = 0.003). The results of this study suggest that HMB could be beneficial for gaining or maintaining body mass during periods of increased training load. However, it appears that HMB may be detrimental to intermittent running ability in this group although further research is required before firm conclusions can be made. Only 6 participants on HMB managed to complete both YoYo IR-1 tests because of injury, a larger sample size is required to fully investigate this potentially negative effect. Further, the mechanisms behind this decrement in performance cannot be fully explained and requires further biochemical and psychological investigation.


Assuntos
Desempenho Atlético/fisiologia , Índice de Massa Corporal , Suplementos Nutricionais , Futebol Americano/fisiologia , Valeratos/farmacologia , Composição Corporal/efeitos dos fármacos , Método Duplo-Cego , Humanos , Masculino , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Valeratos/administração & dosagem , Adulto Jovem
5.
J Exerc Sci Fit ; 16(3): 78-82, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30662498

RESUMO

BACKGROUND/OBJECTIVE: Adventure racing is an ultra-endurance activity that imposes a unique multifaceted stress on the human body. The purpose of this field study was to examine the physiological responses to a 5-day adventure race. METHODS: Eight competitors, two teams (1 female each) in the 2012 GODZone adventure race volunteered. Competitors trekked, cycled and paddled ∼326 km in ∼116 hours. Continuous glucose was measured the day before and throughout. Body mass, urinary solutes, and blood pressure and heart rate during resting, standing, and repeated squat-stand conditions, were assessed pre and post. RESULTS: Despite no changes in mean blood glucose levels, there was increased glycemic variability (Standard deviation glucose; Pre: 0.5 ±â€¯0.1 vs Race: 1.0 ±â€¯0.2 mmol/L, p = 0.02) and periods of hypoglycemia (i.e., Min glucose Pre: 4.1 ±â€¯0.3 vs Race: 3.6 ±â€¯0.5 mmol/L, p = 0.05) during the race. After the race, the blood pressure during resting, standing and squat-stand conditions was significantly lower, by 14 ±â€¯14 mmHg, 16 ±â€¯15 mmHg and 18 ±â€¯15 mmHg (all p < 0.05), respectively, with no change in heart rate. During five-days of adventure racing there is increased glycemic variability and more frequent periods of low blood glucose levels. Additionally, following the race pronounced hypotension is observed in competitors. CONCLUSION: We observed more frequent glucose fluctuations, lower glucose levels and significant perturbations in blood pressure control. Further research is warranted to examine the long-term impact of adventure racing on metabolic and cardiovascular function.

6.
Public Health Nutr ; 19(7): 1279-87, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26347042

RESUMO

OBJECTIVE: To examine the association between cardiorespiratory fitness and dietary patterns in adolescents. DESIGN: Food choice was assessed using the validated New Zealand Adolescent FFQ. Principal components analysis was used to determine dietary patterns. Trained research assistants measured participants' height and body mass. Cardiorespiratory fitness was assessed in a subset of participants using the multistage 20 m shuttle run. The level and stage were recorded, and the corresponding VO2max was calculated. Differences in mean VO2max according to sex and BMI were assessed using t tests, while associations between cardiorespiratory fitness and dietary patterns were examined using linear regression analyses adjusted for age, sex, school attended, socio-economic deprivation and BMI. SETTING: Secondary schools in Otago, New Zealand. SUBJECTS: Students (n 279) aged 14-18 years who completed an online lifestyle survey during a class period. RESULTS: Principal components analysis produced three dietary patterns: 'Treat Foods', 'Fruits and Vegetables' and 'Basic Foods'. The 279 participants who provided questionnaire data and completed cardiorespiratory fitness testing had a mean age of 15·7 (sd 0·9) years. Mean VO2max was 45·8 (sd 6·9) ml/kg per min. The 'Fruits and Vegetables' pattern was positively associated with VO2max in the total sample (ß=0·04; 95%CI 0·02, 0·07), girls (ß=0·06; 95% CI 0·03, 0·10) and boys (ß=0·03; 95% CI 0·01, 0·05). CONCLUSIONS: These results indicate that increase in cardiorespiratory fitness was associated with a healthier dietary pattern, suggesting both should be targeted as part of a global lifestyle approach. Longitudinal studies are needed to confirm this association in relation to health outcomes in New Zealand adolescents.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Dieta Saudável , Adolescente , Composição Corporal , Índice de Massa Corporal , Estudos Transversais , Feminino , Frutas , Humanos , Estilo de Vida , Modelos Lineares , Masculino , Nova Zelândia , Consumo de Oxigênio , Análise de Componente Principal , Fatores Socioeconômicos , Inquéritos e Questionários , Verduras
7.
Public Health Nutr ; 18(8): 1453-60, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25158609

RESUMO

OBJECTIVE: To examine the potential associations between diet quality and multiple measures of body composition in a sample of New Zealand adolescents aged 14-18 years. DESIGN: Cross-sectional survey of eleven high schools in Otago, New Zealand. Each participant completed an online FFQ and a New Zealand Diet Quality Index for Adolescents (NZDQI-A) score was calculated based on variety and adequacy of intake for five major food groups. Besides height and waist circumference measurements, body composition was assessed using segmental bio-impedance analysis. Generalized estimating equations were used to examine associations between diet quality and body composition in models adjusted for sex, age, ethnicity and socio-economic status. SETTING: High schools in Otago, New Zealand. SUBJECTS: High-school students (n 681, 56 % male, mean age 16·1 (sd 1·5) years) participating in the Otago School Students Lifestyle Survey Two. RESULTS: Higher NZDQI-A scores were significantly associated with lower body fat percentage (ß=-0·19; 95 % CI -0·35, -0·04; P=0·014), fat-to-lean mass ratio (ß=-0·26; 95 % CI -0·46, -0·05; P=0·016) and lower fat mass index (ß=-0·23; 95 % CI -0·45, -0·004; P=0·046) after multivariate adjustment. No association was found between NZDQI-A and BMI, waist circumference or waist-to-height ratio. CONCLUSIONS: Diet quality, as measured by NZDQI-A, was associated only with measures of body fat, not measures of overall body size. Measures specific to body fat should be used for more accurate ascertainment of body composition in examining the diet-body composition associations in this age group.


Assuntos
Adiposidade , Dieta , Inquéritos Nutricionais , Adolescente , Composição Corporal , Índice de Massa Corporal , Estudos Transversais , Ingestão de Energia , Feminino , Humanos , Estilo de Vida , Masculino , Análise Multivariada , Nova Zelândia , Fatores Socioeconômicos , Inquéritos e Questionários , Circunferência da Cintura , Razão Cintura-Estatura
8.
J Strength Cond Res ; 28(2): 520-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23669819

RESUMO

The purpose of this study was to compare fluid balance between a resistance and an aerobic training sessions, in elite rugby players. It is hypothesized that resistance exercise will result in a higher prevalence of overdrinking, whereas during the aerobic session, underdrinking will be more prevalent. As with previous fluid balance studies, this was an observational study. Twenty-six players completed the resistance training session, and 20 players completed the aerobic training session. All players were members of an elite rugby union squad competing in the southern hemisphere's premier competition. For both sessions, players provided a preexercise urine sample to determine hydration status, pre- and postexercise measures of body mass, and blood sodium concentration were taken, and the weight of drink bottles were recorded to calculate sweat rates and fluid intake rates. Sweat patches were positioned on the shoulder of the players, and these remained in place throughout each training session and were later analyzed for sodium concentration. The percentage of sweat loss replaced was higher in the resistance (196 ± 130%) than the aerobic training session (56 ± 17%; p = 0.002). Despite this, no cases of hyponatremia were detected. The results also indicated that more than 80% of players started training in a hypohydrated state. Fluid intake seems to differ depending on the nature of the exercise session. In this group of athletes, players did not match their fluid intakes with their sweat loss, resulting in overdrinking during resistance training and underdrinking in aerobic training. Therefore, hydration strategies and education need to be tailored to the exercise session. Furthermore, given the large number of players arriving at training hypohydrated, improved hydration strategies away from the training venue are required.


Assuntos
Futebol Americano/fisiologia , Condicionamento Físico Humano/fisiologia , Treinamento Resistido , Corrida/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Adolescente , Adulto , Peso Corporal , Ingestão de Líquidos , Humanos , Hiponatremia/sangue , Masculino , Condicionamento Físico Humano/métodos , Sódio/análise , Sódio/sangue , Gravidade Específica , Suor/química , Sudorese/fisiologia , Urinálise , Adulto Jovem
9.
J Sports Med Phys Fitness ; 64(5): 446-454, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38305006

RESUMO

BACKGROUND: Nutrition knowledge influences adequate dietary intake in athletes. Inadequate dietary intakes can result in low energy availability (LEA) which can lead to relative energy deficiency in sport (RED-S). To date, there is little information on the relationship between nutrition knowledge and the risk of LEA in female team sport athletes. This study investigates if general and sports nutrition knowledge are associated with the risk of LEA in female team athletes. METHODS: A cross-sectional design was used. Female athletes (>16 years) who participate in team sports in New Zealand were asked to complete an online questionnaire. The LEA in Females Questionnaire and the Abridged Sport Nutrition Knowledge Questionnaire were included. LEA risk and general/sports nutrition knowledge were assessed. The relationship between LEA risk and knowledge was analyzed using the Kruskal-Wallis Test of independent variables and χ2 tests. RESULTS: Among 100 female athletes, 53% were at-risk for LEA, and 70% (N.=67) had poor nutrition knowledge. Athletes who were "at-risk" for LEA and those who were "not at-risk" for LEA did not differ statistically in terms of age (P=0.350) or BMI (P=0.576). Of those "not at risk" 54% had an A-NSK score between 50 and 60% (i.e., average knowledge), whereas 54% of the athletes who were "at risk" for LEA had poor nutrition knowledge. There was no statistical difference between the groups (P=0.273). CONCLUSIONS: The poor nutrition knowledge and the high rates of those "at risk" of LEA among team sports athletes indicates the need for more nutrition education in this population.


Assuntos
Atletas , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Feminino , Estudos Transversais , Adulto , Inquéritos e Questionários , Adulto Jovem , Adolescente , Nova Zelândia , Deficiência Energética Relativa no Esporte , Esportes de Equipe , Fenômenos Fisiológicos da Nutrição Esportiva , Fatores de Risco , Ingestão de Energia
10.
Artigo em Inglês | MEDLINE | ID: mdl-38863417

RESUMO

BACKGROUND: This study aimed to describe the nutrition knowledge, food security risk and eating disorder risk of development male rugby league players. METHODS: Sixty athletes from one Australian professional rugby league club volunteered. A cross sectional online survey questionnaire consisted of three sections (Eating Disorders Inventory (EDI-3), Nutrition Knowledge and Food Security). All athletes completed the online survey without assistance using a personal electronic device. RESULTS: The mean total knowledge score was 65.7±13.1%. There was a positive relationship between age and knowledge score, P=0.050, r2=0.06. The majority of players had breakfast everyday (N.=45, 73.8%), took pack lunches (N.=33, 55.0%), and had homemade evening meals (N.=55, 91.7%). The majority of players ate more than 1 hour before training (N.=45, 75%) and all players (n=60, 100%) ate within half an hour of training finishing. The majority of participants agreed that nutrition could influence physical and cognitive aspects of nutrition however, skill-based activities were perceived by fewer participants to be influenced by nutrition. The majority (N.=38, 63.3%) had high food security, six (10.0%) had marginal food security, whereas 10 (16.7%) and six (10.0%) had low and very low security respectively. CONCLUSIONS: These results show a concerning levels of eating disorder risk, food insecurity and poor nutrition knowledge amongst male development rugby league players. However, it does show that they believe nutrition can impact their health and performance, and they do mostly appear to adhere to the nutrition principals for optimising health and performance.

11.
J Sports Med Phys Fitness ; 64(8): 822-830, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38470016

RESUMO

BACKGROUND: There have been several published studies on the prevalence of low energy availability (LEA) risk amongst North American and European endurance athletes. Yet the prevalence and risk factors amongst rugby league players are less well understood. This study assessed the prevalence of low energy availability risk, eating disorder risk, and food security amongst players from a female National Rugby League squad in Australia. METHODS: Players from one Australian professional rugby league club volunteered to participate in the study. An online questionnaire was conducted to determine the prevalence of low energy availability (Low Energy Availability in Females Questionnaire [LEAF-Q]), eating disorder risk (Eating Disorders Inventory [EDI-3]), and food security. RESULTS: Differences between those "at risk" and "not at risk" based on their total LEAF-Q score were determined. Of the 28 players, 64% (N.=18) were at risk of LEA. Raw scores for the EDI-3 subscales, body dissatisfaction (P=0.043), bulimia (P=0.002), composite score (P=0.038), were significantly higher for those at risk and not at risk of LEA. Forty percent of players had some level of food insecurity. CONCLUSIONS: The results suggest LEA risk is similar to other populations and those at risk of LEA are more likely to have an elevated clinical risk of eating disorders. Food security is also an issue in this population and could contribute to LEA risk for some. Future research is needed amongst team sports athletes to understand interplay between eating disorder risk and food insecurity with LEA risk.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos , Insegurança Alimentar , Futebol Americano , Humanos , Feminino , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Austrália/epidemiologia , Adulto Jovem , Fatores de Risco , Inquéritos e Questionários , Adulto , Prevalência , Atletas/estatística & dados numéricos , Insatisfação Corporal , Ingestão de Energia
12.
Nutr J ; 12: 51, 2013 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-23617772

RESUMO

BACKGROUND: Associations between food choice and body composition in previous studies of adolescents have been inconsistent. This may be due to the body composition measures used, or these associations may be affected by the dieting status of adolescents. The objective of this study was to investigate the association between dietary patterns and body composition in adolescents, and determine if these associations are moderated by dieting status. METHODS: Information on food consumption and current dieting status was collected, using a web-based survey, in 681 adolescents (mean age 15.8 (SD 0.9) years) from schools in Otago, New Zealand. Non-dieters were defined as those reporting not being on a diet as they were "happy with their weight". Principal components analysis (PCA) was used to determine dietary patterns. Body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), fat mass index (FMI), and fat-free mass index (FFMI) were examined as outcomes. Generalized estimating equations were used to examine associations between dietary patterns and body composition. RESULTS: PCA produced three dietary patterns: 'Treat Foods', 'Fruits and Vegetables', and 'Basic Foods'. A standard deviation increase in 'Basic Foods' was associated with a 3.58% decrease in FMI (95%CI -6.14, -0.94) in the total sample. When separate sex analysis was undertaken significant negative associations were found in boys only, between the 'Basic Food' score and WC, WHtR, FMI, and FFMI, while the 'Fruits and Vegetables' pattern was negatively associated with FMI. Associations between 'Treat Foods' and BMI, WC, and WHtR in non-dieters were positive, while these associations were negative for all other participants. CONCLUSIONS: Significant associations were found between dietary patterns and indices of both central and total adiposity, but not BMI. Therefore using only BMI measures may not be useful in this age group. Since our results were significant for boys and not girls, nutrition messages designed to prevent obesity may be particularly important for adolescent boys. As an interaction between dieting status and 'Treat Foods' existed, future studies should also explore the role of dieting when investigating food choice and body composition.


Assuntos
Composição Corporal , Comportamento Alimentar , Estado Nutricional , Absorciometria de Fóton , Adiposidade , Adolescente , Índice de Massa Corporal , Estudos Transversais , Dieta , Inquéritos sobre Dietas , Feminino , Frutas , Humanos , Masculino , Nova Zelândia , Obesidade/prevenção & controle , Fatores Sexuais , Inquéritos e Questionários , Verduras , Circunferência da Cintura
13.
Nutr J ; 12: 128, 2013 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-24034352

RESUMO

BACKGROUND: While relationships between sleep and BMI have been extensively studied in younger children the effect of sleep duration on adiposity in adolescents, who are undergoing rapid growth periods, is less well known. There is also a lack of consistent evidence on the role of sleep on other measures of adolescent body composition which may be more reflective of health than BMI in this age group. Previous research investigating whether these relationships differ between sexes is also inconsistent. Therefore the objective of this study was to investigate relationships between sleep duration and multiple body composition measures in older adolescents and to investigate if these relationships differ between boys and girls. METHODS: A web-based cross-sectional survey and anthropometric measurement of 685 adolescents (mean age 15.8 years) from 11 schools in Otago, New Zealand. Height and weight were measured by trained researchers and fat mass and fat-free mass were estimated using bio-impedance. Generalised estimating equations were used to examine associations between sleep duration and the following body composition measures: BMI, waist circumference (WC), waist-to-height ratio (WHtR), fat mass index (FMI), and fat-free mass index (FFMI). Analyses were adjusted for ethnicity, deprivation, the number of screens in the bedroom and fruit and vegetable consumption. RESULTS: When data from all participants were analysed together, no significant relationships were seen between sleep duration and any body composition measure but significant sex interactions were seen. An hour increase in average nightly sleep duration in boys only was associated with decreases of 1.2% for WC, 0.9% for WHtR, 4.5% for FMI and 1.4% for FFMI in multivariate models. Similar results were seen for weekday and weekend night sleep duration. CONCLUSIONS: Sex specific factors may play a role in relationships between sleep and body composition in older adolescents. The results in boys were most pronounced for FMI, a measure of total adiposity, which suggests that insufficient sleep in adolescent boys may affect fat mass more than lean mass and that the use of measures such as BMI may result in an under-estimation of relationships.


Assuntos
Adiposidade , Comportamento do Adolescente , Desenvolvimento do Adolescente , Dieta/efeitos adversos , Sobrepeso/etiologia , Privação do Sono/fisiopatologia , Sono , Adiposidade/etnologia , Adolescente , Comportamento do Adolescente/etnologia , Índice de Massa Corporal , Estudos de Coortes , Estudos Transversais , Dieta/etnologia , Comportamento Alimentar/etnologia , Feminino , Inquéritos Epidemiológicos , Humanos , Internet , Masculino , Nova Zelândia/epidemiologia , Sobrepeso/epidemiologia , Sobrepeso/etnologia , Sobrepeso/prevenção & controle , Prevalência , Caracteres Sexuais , Privação do Sono/etnologia , Saúde Suburbana/etnologia , Saúde da População Urbana/etnologia
14.
BMC Public Health ; 13: 562, 2013 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-23759064

RESUMO

BACKGROUND: As there is no population-specific, simple food-based diet index suitable for examination of diet quality in New Zealand (NZ) adolescents, there is a need to develop such a tool. Therefore, this study aimed to develop an adolescent-specific diet quality index based on dietary information sourced from a Food Questionnaire (FQ) and examine its validity relative to a four-day estimated food record (4DFR) obtained from a group of adolescents aged 14 to 18 years. METHODS: A diet quality index for NZ adolescents (NZDQI-A) was developed based on 'Adequacy' and 'Variety' of five food groups reflecting the New Zealand Food and Nutrition Guidelines for Healthy Adolescents. The NZDQI-A was scored from zero to 100, with a higher score reflecting a better diet quality. Forty-one adolescents (16 males, 25 females, aged 14-18 years) each completed the FQ and a 4DFR. The test-retest reliability of the FQ-derived NZDQI-A scores over a two-week period and the relative validity of the scores compared to the 4DFR were estimated using Pearson's correlations. Construct validity was examined by comparing NZDQI-A scores against nutrient intakes obtained from the 4DFR. RESULTS: The NZDQI-A derived from the FQ showed good reliability (r = 0.65) and reasonable agreement with 4DFR in ranking participants by scores (r = 0.39). More than half of the participants were classified into the same thirds of scores while 10% were misclassified into the opposite thirds by the two methods. Higher NZDQI-A scores were also associated with lower total fat and saturated fat intakes and higher iron intakes. CONCLUSIONS: Higher NZDQI-A scores were associated with more desirable fat and iron intakes. The scores derived from either FQ or 4DFR were comparable and reproducible when repeated within two weeks. The NZDQI-A is relatively valid and reliable in ranking diet quality in adolescents at a group level even in a small sample size. Further studies are required to test the predictive validity of this food-based diet index in larger samples.


Assuntos
Dieta/estatística & dados numéricos , Política Nutricional , Adolescente , Serviços de Saúde do Adolescente , Registros de Dieta , Comportamento Alimentar , Feminino , Humanos , Masculino , Nova Zelândia , Reprodutibilidade dos Testes , Inquéritos e Questionários
16.
Nutr Rev ; 81(7): 869-886, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-36367830

RESUMO

Females are often underrepresented in the scientific literature, but awareness of the need for female-specific research is increasing. Review articles have been published on the effects of the menstrual cycle on aspects of exercise performance and physiology, yet to date no research has reviewed the effect of menstrual cycle phase on dietary energy intake. Fluctuations in endogenous sex hormones across the menstrual cycle influence a range of physiological processes, including those involved in nutritional status. Observational research typically quantifies female athletes' nutritional intakes at a single time point; however, this may provide inaccurate information if dietary intake fluctuates across the menstrual cycle. Similarly, this may have implications for interventional research, where dietary intake is often poorly controlled or monitored. This review aimed to synthesize the published literature on dietary energy intakes of naturally menstruating females in various phases of the menstrual cycle. The review critiques the relevant literature in light of recent publications on good practice for female research, explores the impact of the menstrual cycle on energy intake, identifies gaps within the evidence base, and informs future research. Overall, energy intake appears to be lower in the follicular phase compared with the luteal phase, with a particular decrease in the days leading up to and including ovulation. The magnitude of these fluctuations is not yet clearly quantifiable and most likely varies, both between individuals, and from cycle to cycle. This review notes the lack of high-quality research investigating the energy intakes of females across the menstrual cycle, and the very limited data available for female athletes and others who undertake large amounts of physical activity. It also highlights the need for researchers to take into consideration anovulatory cycles and the potential effects of premenstrual disorders on dietary intake.


Assuntos
Ingestão de Energia , Ciclo Menstrual , Feminino , Humanos , Ciclo Menstrual/fisiologia , Ingestão de Energia/fisiologia , Fase Luteal/fisiologia , Dieta , Ingestão de Alimentos
17.
Nutr J ; 11: 65, 2012 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-22950540

RESUMO

BACKGROUND: Due to the absence of a current and validated food frequency questionnaire (FFQ) for use in New Zealand adolescents, there is a need to develop one as a cost-effective way to assess adolescents' food patterns. This study aims to examine the test-retest reliability and relative validity of the New Zealand Adolescent FFQ (NZAFFQ) to assess food group intake in adolescents aged 14 to 18 years. METHODS: A non-quantitative (without portion size), 72-item FFQ was developed and pretested. Fifty-two participants (aged 14.9 ± 0.8 years) completed the NZAFFQ twice within a two-week period for test-retest reliability. Forty-one participants (aged 15.1 ± 0.9 years) completed a four-day estimated food record (4DFR) in addition to the FFQs to enable assessment of validity. Spearman's correlations and cross-classification analyses were used to examine relative validity while intra-class correlations were additionally used for test-retest reliability. RESULTS: Weekly intakes were estimated for each food item and aggregated into 34 food groups. The median Spearman's correlation coefficient (SCC) between FFQ administrations was 0.71. SCCs ranged from 0.46 for fruit juice or cordial to 0.87 for non-standard milk. The median intra-class correlation coefficient (ICC) between FFQ administrations was 0.69. The median SCC between food groups from the FFQ and the 4DFR was 0.40 with the highest SCC seen for standard milk (0.70). The exact agreement between the methods in ranking participants into thirds was highest for meat alternatives (78%), but lowest for red or yellow vegetables and potatoes (27%). The mean percent of participants misclassified into extreme thirds for food group intake was 12%. CONCLUSIONS: Despite a small sample size, the NZAFFQ exhibited good to excellent short-term test-retest reliability and reasonable validity in ranking the majority of the food group intakes among adolescents aged 14 to 18 years. The comparability of the validity to that in the current literature suggests that the NZAFFQ may be used among adolescent New Zealanders to identify dietary patterns and rank them according to food group intake.


Assuntos
Comportamento do Adolescente/etnologia , Inquéritos sobre Dietas/métodos , Dieta/etnologia , Comportamento Alimentar/etnologia , Adolescente , Dieta/efeitos adversos , Registros de Dieta , Feminino , Humanos , Masculino , Nova Zelândia , Avaliação Nutricional , Reprodutibilidade dos Testes , Inquéritos e Questionários
18.
Int J Sport Nutr Exerc Metab ; 22(1): 19-23, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22248496

RESUMO

Endurance events>10 hr are becoming increasingly popular but provide numerous physiological challenges, several of which can be attenuated with optimal nutritional intakes. Previous studies in ultraendurance races have reported large energy deficits during events. The authors therefore aimed to assess nutritional intakes in relation to performance among ultraendurance cyclists. This observational study included 18 cyclists in a 384-km cycle race. At race registration each cyclist's support crew was provided with a food diary for their cyclist. On completion of the race, cyclists were asked to recall their race food and drink intakes. All food and fluids were analyzed using a computer software package. Mean (SD) time to complete the race was 16 hr 21 min (2 hr 2 min). Mean (SD) energy intake was 18.7 (8.6) MJ, compared with an estimated energy requirement for the race of 25.5 (7.4) MJ. There was a significant negative relationship between energy intake and time taken to complete the race (p=.023, r²=-.283). Mean (SD) carbohydrate, fat, and protein intakes were 52 (27), 15.84 (56.43), and 2.94 (7.25) g/hr, respectively. Only carbohydrate (p=.015, r²=-.563) and fat intake (p=.037, r²=-.494) were associated with time taken to complete the race. This study demonstrates the difficulties in meeting the high energy demands of ultraendurance cycling. The relationship between energy intake and performance suggests that reducing the energy deficit may be advantageous. Given the high carbohydrate intakes of these athletes, increasing energy intake from fat should be investigated as a means of decreasing energy deficits.


Assuntos
Desempenho Atlético/fisiologia , Ingestão de Energia , Resistência Física/fisiologia , Aptidão Física/fisiologia , Estresse Fisiológico , Adulto , Idoso , Ciclismo , Registros de Dieta , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Suplementos Nutricionais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Substâncias para Melhoria do Desempenho/administração & dosagem , Redução de Peso
19.
J Sci Med Sport ; 25(10): 794-799, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35909054

RESUMO

OBJECTIVES: The aim of this study was to develop and validate a questionnaire assessing knowledge of signs and symptoms of relative energy deficiency in sport among healthcareprofessionals and physically active individuals. DESIGN: Cross-sectional study. METHODS: The questionnaire was created in two phases: 1)Item development was established through a literature review, expert review (n = 4), and pre-testing among healthcare professionals, dietetic students, and the general population (n = 35). 2) Validity (item analysis, construct validity) and internal reliability were assessed by administrating the questionnaire to healthcare professionals (n = 97) and physically active individuals who engaged in moderate to intense physical activity (n=77). The questionnaire was re-administered in a subset of the same groups (n = 88) for test-retest reliability. RESULTS: The expert responses showed >80% acceptability and pretesting through interviews indicated good content and face validity. Item response analysis resulted in removal of 6 items due to low discrimination ability. Significantly higher knowledge scores in health professionals compared with non-health professionals (mean difference (95% CI) = 2.8 (1.9, 3.7)) confirmed construct validity. Internal consistency, assessed using Cronbach's alpha (α = 0.79), and test-retest reliability using intra-class correlation coefficients (intra-class correlation coefficients = 0.80; Spearman's correlation = 0.84, p < 0.001) were good. The final questionnaire had 18 items assessing knowledge of signs and symptoms of Relative Energy Deficiency in Sport. CONCLUSIONS: The questionnaire provides a valid and reliable tool to assess knowledge of signs and symptoms of Relative Energy Deficiency in Sport among health professionals and physically active individuals, which could guide future education requirements by assessing current knowledge.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Deficiência Energética Relativa no Esporte , Estudos Transversais , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
20.
J Sports Med Phys Fitness ; 60(2): 289-293, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31665878

RESUMO

BACKGROUND: Iron deficiency is a common deficiency disease worldwide with athletes at increased risk. METHODS: A proposed new mechanism of exercise-induced iron deficiency in athletes involves the iron-regulatory hormone hepcidin, however, there is limited information on this amongst elite athletes. This study describes iron status in elite female rugby Sevens players. RESULTS: Blood samples were collected at the start and mid-season and analyzed for serum iron, serum ferritin (SF), soluble transferring receptor (sTfR), high sensitivity C-reactive Protein (hsCRP) and hepcidin. Of the 17 players 18% were iron deficient (SF<30 µg/L) with 29-35% of players with sub-optimal iron stores at some point during the study (SF<45 µg/L). Serum hepcidin was strongly correlated with SF (r=0.61, P=0.0001). CONCLUSIONS: Some elite female rugby Sevens players have sub-optimal iron stores over the course of a season.


Assuntos
Hepcidinas/sangue , Ferro/sangue , Adulto , Atletas/estatística & dados numéricos , Proteína C-Reativa/análise , Feminino , Ferritinas/sangue , Futebol Americano/estatística & dados numéricos , Humanos , Deficiências de Ferro , Estudos Longitudinais , Adulto Jovem
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