RESUMO
PURPOSE: The strict lockdown implemented due the COVID-19 pandemic is generating a great impact on wellbeing and health-related quality of life (HRQoL) in people with cancer. We aimed to evaluate the efficacy and feasibility of an online home-based exercise intervention performed during a lockdown period analysing its effects on body composition, physical fitness, and HRQoL in breast cancer survivors. METHODS: Fifteen women with breast cancer receiving hormonal therapy (55.5 ± 6.7 years) were included in the study. The exercise intervention consisted of two weekly sessions of remotely supervised functional training (60 min per day) and two weekly sessions of unsupervised aerobic training (20-30 min/session; 60-85% of maximum heart rate) for a total of 16 weeks. DXA absorptiometry was used for the assessment of body composition. Functional assessment included cardiorespiratory fitness (CRF) by Rockport walking test, upper and lower body strength (grip strength, arm curl test, and chair stand test), walking speed (brisk walking test), and agility (8-foot up-and-go test). The HRQoL was evaluated with the QLQ-BR23 questionnaire. The adherence to the intervention was measured as the percentage of online classes attended. RESULTS: Rate of adherence for the online exercise intervention was 90 ± 17%. The exercise intervention induced significant (p < 0.05) improvements in physical fitness: CRF (+ 9%), right arm and lower limb strength (+ 10% and + 18%, respectively) and lower limbs lean mass (+ 2% and + 3.5% for left and right leg, respectively). CONCLUSION: This feasibility study suggests that an online home-based exercise intervention during COVID-19 lockdown could improve physical fitness and body composition in breast cancer survivors even in a context of heightened concern for future health.
Assuntos
Neoplasias da Mama , COVID-19 , Sobreviventes de Câncer , Controle de Doenças Transmissíveis , Terapia por Exercício , Estudos de Viabilidade , Feminino , Humanos , Força Muscular/fisiologia , Pandemias , Qualidade de VidaRESUMO
BACKGROUND: Increased physical activity (PA) is a very important factor in a healthy aging lifestyle. Psychosocial factors have also a main role in the initiation and maintenance of this behavior, but nowadays its implications for frailty elderly people are unknown, therefore, the aim of this study was to identify the psychosociological variables of behavior change that influence the practice of (PA) in frail and prefrail elderly. METHODS: A total of 103 frail and pre-frail elderly people (72 females) participated in this cross-sectional study, on the framework of the EXERNET-Elder3.0 project. Age ranged from 68-94 years (mean = 80.4 ± 5.9 years). Individualized face-to-face interviews according to the constructs of the Transtheoretical Model of Change (TTM) [(decisional balance (DB) and self-efficacy (SE)], social support (SS) (family and friends) and outcome expectations (OE) were administered to all participants. RESULTS: Significant differences were found in DB, perceived benefits (PBn), SE, family-related SS and OE as a function of stages of change (SoC) (p < 0.005), but no significant were found in perceived barriers (PBrr) (p = 0.259) and friends-related SS (p = 0.068). According to the Scheffé post-hoc test, those in advanced SoC (Action-Maintenance), scored higher than those in lower SoC (Precontemplation-Contemplation and Preparation). CONCLUSION: The scores obtained from the study variables differed according to the SoC, supporting the external validity for the use of the TTM in frailty elderly. Further research is needed to determine the impact of PBrr and friends-related SS on this people, as well as to identify the validity of this model in the long-term in this population.
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Idoso Fragilizado , Fragilidade , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Exercício Físico/psicologia , Feminino , Fragilidade/diagnóstico , Avaliação Geriátrica , Humanos , Masculino , AutoeficáciaRESUMO
This study systematically reviewed and quantified the effects of running a long-distance race (LDR) on heart rate variability (HRV) and arterial stiffness (AS). All types of races of a distance equal to or greater than a marathon (≥42.2 km) were included. A total of 2,220 articles were identified, 52 were included in the qualitative analysis, and 48 were meta-analysed. The standardised mean difference pre- and post-race of various time-domain and frequency-domain indices of HRV, mean arterial blood pressure (MAP), systolic blood pressure (SBP), diastolic blood pressure (DBP) and carotid-femoral pulse wave velocity (cfPWV) was calculated. Regarding HRV, there was a significant decrease in most of the variables considered as markers of parasympathetic activity, indicating a shift of autonomic balance towards a reduced vagal tone. Regarding vascular variables, there was a significant drop in blood pressure and reduced AS. In conclusion, running an LDR seems to have a considerable acute effect on the autonomic nervous system, haemodynamics, and vascular properties. The observed effects could be categorised within the expected acute responses to long-lasting, strenuous exercise.
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Rigidez Vascular , Sistema Nervoso Autônomo , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Análise de Onda de Pulso , Rigidez Vascular/fisiologiaRESUMO
ABSTRACT: Muniz-Pardos, B, Gomez-Bruton, A, Matute-Llorente, A, Gonzalez-Aguero, A, Gomez-Cabello, A, Gonzalo-Skok, O, Casajus, JA, and Vicente-Rodriguez, G. Nonspecific resistance training and swimming performance: Strength or power? A systematic review. J Strength Cond Res 36(4): 1162-1170, 2022-The purpose of this systematic review was to determine the type of nonspecific resistance intervention that is more effective to enhance swimming performance and to determine the nonspecific strength- or power-related variable that better predicts swimming performance. A search was conducted on PubMed, Cochrane Plus, and SportDiscus up to June 2018. Studies were distributed into 4 categories: dry-land strength (DLS), dry-land power (DLP), combination of training methods, and strength and power in start performance. From 1,844 citations, 33 met the inclusion criteria. Cross-sectional DLS studies showed positive associations between swimming performance and DLS development (especially through upper-body isometric assessments), although the efficacy of DLS training interventions remains unclear. Dry-land power training (principally through plyometrics) was a proficient, nonspecific method to enhance swimming block start performance (SBS; the start phase off the block and during the first 5-15 m), and jump assessment was the best predictor of SBS. Some pioneering nonspecific practices such as the acute exposure to high altitude or the maintenance of a high core temperature during the transition phase before competition seem to improve performance, although more research is required to confirm their efficacy. Further high-quality intervention studies are required to clarify the effect of DLP training on sprint swimming performance.
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Desempenho Atlético , Treinamento Resistido , Estudos Transversais , Humanos , Força Muscular , Treinamento Resistido/métodos , NataçãoRESUMO
OBJECTIVES: To assess the influence of muscle power and adiposity on all-cause mortality risk and to evaluate the 'fat but powerful' (F+P) (or 'fat but fit') paradox in older adults. METHODS: A total of 2563 older adults (65â91 years old) from the EXERNET multicentre study were included. Adiposity (body mass index (BMI), waist circumference, body fat percentage (BF%) and fat index), allometric and relative power (sit-to-stand muscle power test) and various covariates (age, sex, hypertension, smoking status and walking and sitting times per day) were registered at baseline. All-cause mortality was recorded during a median follow-up of 8.9 years. Participants were classified into four groups: lean and powerful (L+P), F+P, lean but weak and fat and weak (F+W). Cox proportional hazard regression models and adjusted HRs were calculated. RESULTS: According to BMI and waist circumference, all-cause mortality risk was reduced in the F+P (HR=0.55 and 0.63, p=0.044 and 0.049, respectively) and L+P (HR=0.57 and 0.58, p=0.043 and 0.025, respectively) groups. According to BF%, all-cause mortality decreased in the L+P group (HR=0.53; p=0.021), and a trend for a reduction was reported in the F+P group (HR=0.57; p=0.060). According to fat index, a survival benefit was only noted in the L+P group (HR=0.50; p=0.049). Higher levels of relative power reduced all-cause mortality risk among older people (HR=0.63 and 0.53, p=0.006 and 0.011, respectively). CONCLUSION: Powerful older people exhibited a reduced 9-year all-cause mortality regardless of BMI, waist circumference and BF%. Obesity according to fat index blunted the survival benefits of being powerful.
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Adiposidade/fisiologia , Força Muscular/fisiologia , Obesidade/mortalidade , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco , Circunferência da CinturaRESUMO
This work aims to validate the Polar H7 heart rate (HR) sensor for heart rate variability (HRV) analysis at rest and during various exercise intensities in a cohort of male volunteers with different age, body composition and fitness level. Cluster analysis was carried out to evaluate how these phenotypic characteristics influenced HR and HRV measurements. For this purpose, sixty-seven volunteers performed a test consisting of the following consecutive segments: sitting rest, three submaximal exercise intensities in cycle-ergometer and sitting recovery. The agreement between HRV indices derived from Polar H7 and a simultaneous electrocardiogram (ECG) was assessed using concordance correlation coefficient (CCC). The percentage of subjects not reaching excellent agreement (CCC > 0.90) was higher for high-frequency power (PHF) than for low-frequency power (PLF) of HRV and increased with exercise intensity. A cluster of unfit and not young volunteers with high trunk fat percentage showed the highest error in HRV indices. This study indicates that Polar H7 and ECG were interchangeable at rest. During exercise, HR and PLF showed excellent agreement between devices. However, during the highest exercise intensity, CCC for PHF was lower than 0.90 in as many as 60% of the volunteers. During recovery, HR but not HRV measurements were accurate. As a conclusion, phenotypic differences between subjects can represent one of the causes for disagreement between HR sensors and ECG devices, which should be considered specifically when using Polar H7 and, generally, in the validation of any HR sensor for HRV analysis.
Assuntos
Eletrocardiografia , Exercício Físico , Frequência Cardíaca , Adulto , Idoso , Composição Corporal , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Childhood obesity has become a major health problem in children under the age of 5 years. Providing reference standards would help paediatricians to detect and/or prevent health problems related to both low and high levels of body mass and to central adiposity later in life. Therefore, the aim of this study was to examine the prevalence of different weight status categories and to provide sex- and age-specific anthropometry reference standards for Spanish preschool children. METHODS: A total of 3178 preschool children (4.59±0.87 years old) participated in this study. Prevalence of different degrees of obesity (mild, severe, and morbid) and other weight status categories were determined. RESULTS: Reference standards were obtained. Prevalence of overweight and obese preschool children in the Spanish population ranged from 21.4 to 34.8%. Specifically, the obesity prevalence was 3.5, 1.2, and 1.3% of these subjects were categorized as mild, severe, and morbid obese. Sex- and age-specific reference standards for anthropometric parameters are provided for every 0.25 years (i.e. every trimester of life). CONCLUSION: Our results show a high prevalence of overweight/obese preschoolers. The provided sex- and age-specific anthropometric reference standards could help paediatricians to track and monitor anthropometric changes at this early stage in order to prevent overweight/obesity.
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Antropometria , Obesidade Mórbida/diagnóstico , Obesidade Mórbida/epidemiologia , Obesidade Infantil/diagnóstico , Obesidade Infantil/epidemiologia , Adiposidade , Fatores Etários , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Obesidade Mórbida/fisiopatologia , Obesidade Infantil/fisiopatologia , Valor Preditivo dos Testes , Prevalência , Padrões de Referência , Índice de Gravidade de Doença , Fatores Sexuais , Espanha/epidemiologia , Aumento de PesoRESUMO
The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3-5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks' λ = 0.383; F10,5996 = 369.64; p < 0.001, ηp 2 = 0.381) and of quarter (Wilks' λ = 0.874; F15,8276.6 = 27.67; p < 0.001; ηp 2 = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers.
Assuntos
Desenvolvimento Infantil/fisiologia , Aptidão Física , Fatores Etários , Estatura , Peso Corporal , Aptidão Cardiorrespiratória , Pré-Escolar , Teste de Esforço , Feminino , Humanos , Masculino , Destreza Motora/fisiologia , Força Muscular/fisiologia , Equilíbrio Postural/fisiologia , EspanhaRESUMO
This study examined (1) the association of dietary energy density from solid (EDS) and solid plus liquids (EDSL) with adiposity and cardiometabolic risk factors (CRF) in children with overweight and obesity, (2) the effect of under-reporting on the mentioned associations and (3) whether the association between ED and body composition and CRF is influenced by levels of physical activity. In a cross-sectional design, 208 overweight and obese children (8-12-year-old; 111 boys) completed two non-consecutive 24 h recalls. ED was calculated using two different approaches: EDS and EDSL. Under-reporters were determined with the Goldberg method. Body composition, anthropometry and fasting blood sample measurements were performed. Moderate to vigorous physical activity (MVPA) was registered with accelerometers (7-d-register). Linear regressions were performed to evaluate the association of ED with the previously mentioned variables. Neither EDS nor EDSL were associated with body composition or CRF. However, when under-reporters were excluded, EDS was positively associated with BMI (P=0·019), body fat percentage (P=0·005), abdominal fat (P=0·008) and fat mass index (P=0·018), while EDSL was positively associated with body fat percentage (P=0·008) and fat mass index (P=0·026). When stratifying the group according to physical activity recommendations, the aforementioned associations were only maintained for non-compliers. Cluster analysis showed that the low-ED and high-MVPA group presented the healthiest profile for all adiposity and CRF. These findings could partly explain inconsistencies in literature, as we found that different ED calculations entail distinct results. Physical activity levels and excluding under-reporters greatly influence the associations between ED and adiposity in children with overweight and obesity.
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Composição Corporal , Doenças Cardiovasculares/etiologia , Dieta/efeitos adversos , Doenças Metabólicas/etiologia , Obesidade Infantil/fisiopatologia , Gordura Abdominal , Adiposidade , Antropometria , Índice de Massa Corporal , Criança , Estudos Transversais , Inquéritos sobre Dietas , Ingestão de Energia , Exercício Físico , Feminino , Humanos , Masculino , Obesidade Infantil/complicaçõesRESUMO
This study aimed to analyse the association between socioeconomic status (SES) and fatness and fitness in preschoolers. 2,638 preschoolers (3-5 years old; 47.2% girls) participated. SES was estimated from the parental educational and occupational levels, and the marital status. Fatness was assessed by body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR). Physical fitness components were assessed using the PREFIT battery. Preschoolers whose parents had higher educational levels had lower fatness (P < 0.05). BMI significantly differed across occupational levels of each parent (P < 0.05) and WHtR across paternal levels (P = 0.004). Musculoskeletal fitness was different across any SES factor (P < 0.05), except handgrip across paternal occupational levels (P ≥ 0.05). Preschoolers with high paternal occupation had higher speed/agility (P = 0.005), and those with high or low maternal education had higher VO2max (P = 0.046). Odds of being obese and having low musculoskeletal fitness was lower as SES was higher (P < 0.05). Those with married parents had higher cardiorespiratory fitness than single-parent ones (P = 0.010). School-based interventions should be aware of that children with low SES are at a higher risk of obesity and low fitness already in the first years of life.
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Adiposidade , Aptidão Cardiorrespiratória , Classe Social , Índice de Massa Corporal , Criança , Pré-Escolar , Estudos Transversais , Características da Família , Feminino , Força da Mão , Humanos , Masculino , Consumo de Oxigênio , Circunferência da Cintura , Razão Cintura-EstaturaRESUMO
The aims of this study were (a) to determine which of the most used anthropometric equations was the most accurate to estimate percentage of body fat (%BF), (b) to develop a new specific anthropometric equation, and (c) to validate this football-specific equation. A total of 126 (13.3 ± 0.6 years) football players (86 males and 40 females) participated in the present study. Participants were divided into two groups: 98 players were included in the assessment of existing equations and in the development of the new prediction equation, and 28 players were used to validate it. %BF was measured with dual-energy X-ray absorptiometry (DXA) and also estimated with six different %BF anthropometric equations: Johnston, Slaughter, Carter, Faulkner, Deurenberg, and Santi-Maria. Paired t tests were used to analyze differences between methods. A football-specific equation was developed by a stepwise linear regression. The existing anthropometric equations showed significant bias for %BF when compared with DXA (p < .001; constant error ranged from -4.57% to 9.24%; standard error of estimate ranged from 2.46 to 4.20). On the other hand, the developed football-specific equation was %BF = 11.115 + 0.775 (triceps skinfold) + 0.193 (iliac crest skinfold) - 1.606 (sex). The developed equation demonstrated neither %BF differences (p = .121; constant error = 0.57%; standard error of estimate = 0.36) when compared with DXA, presenting a high cross-validation prediction power (R2 = .85). Published anthropometric equations were not accurate to estimate %BF in adolescent football players. Due to the fact that the developed football-specific equation showed neither differences nor heteroscedasticity when compared with DXA, this equation is recommended to assess %BF in adolescent football players.
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Adiposidade , Antropometria/métodos , Futebol , Absorciometria de Fóton , Adolescente , Feminino , Humanos , Masculino , Dobras CutâneasRESUMO
Muniz-Pardos, B, Gomez-Bruton, A, Matute-Llorente, A, Gonzalez-Aguero, A, Gomez-Cabello, A, Gonzalo-Skok, O, Casajus, JA, and Vicente-Rodriguez, G. Swim-specific resistance training: A systematic review. J Strength Cond Res 33(10): 2875-2881, 2019-The purpose of this systematic review was to determine which type of swim-specific training is most beneficial to enhance swimming performance and to determine which specific strength- or power-related tests better predict swimming performance. A search was conducted on PubMed, Cochrane Plus, and SPORTDiscus up to June 2018. Studies were distributed into 2 main categories: swim-specific dry land resistance training (SDLRT) and specific in-water swimming power training (SSWPT). From 1,844 citations, 25 met the inclusion criteria. It was determined that SSWPT was the most appropriate method to improve swimming performance, with tethered swimming protocols being the most studied and effective. In addition, SDLRT was a competent method to enhance swimming performance, and specifically, the inclusion of inertial training might evoke greater improvements in both strength/power capacities and swimming performance, than traditional resistance training. In conclusion, tether forces showed the greatest associations with swimming performance, although the efficacy of tethered swimming as an SSWPT method is yet to be confirmed. Further research should focus on the effects of SDLRT to verify the greater transfer of dry land resistance practices to swimming performance, with inertial training being potentially more beneficial than traditional resistance training.
Assuntos
Desempenho Atlético , Treinamento Resistido/métodos , Natação/fisiologia , Teste de Esforço/métodos , Humanos , ÁguaRESUMO
The aim of this study was to analyze the effects of soccer practice on bone in male and female children and adolescents. MEDLINE, PubMed, SPORTDiscus and Web of Science databases were searched for scientific articles published up to and including October 2016. Twenty-seven studies were included in this systematic review (13 in the meta-analysis). The meta-analysis was performed by using OpenMeta[Analyst] software. It is well documented that soccer practice during childhood provides positive effects on bone mineral content (BMC) and density (BMD) compared to sedentary behaviors and other sports, such as tennis, weightlifting, or swimming. Furthermore, soccer players present higher BMC and BMD in most weight-bearing sites such as the whole body, lumbar spine, hip, and legs. Moreover, bone differences were minimized between groups during prepuberty. Therefore, the maturity status should be considered when evaluating bone. According to meta-analysis results, soccer practice was positively associated with whole-body BMD either in males (mean difference 0.061; 95%CI, 0.042-0.079) or in females (mean difference 0.063; 95%CI, 0.026-0.099). CONCLUSION: Soccer may be considered a sport that positively affects bone mass during growth. Pubertal soccer players presented increased bone mass compared to controls or other athletes; however, these bone differences are minimized during the prepubertal stage. What is known: ⢠It has been described that childhood and adolescence are important periods for bone mass and structure. ⢠Previous studies have demonstrated that soccer participation improves bone mass in male and female children and adolescents. What is new: ⢠The differences between soccer players and controls are more marked during puberty than prepuberty. ⢠Weight-bearing sites such as lumbar spine, hip, femoral neck, trochanter, intertrochanteric region and both legs are particularly sensitive to soccer actions.
Assuntos
Densidade Óssea/fisiologia , Desenvolvimento Ósseo/fisiologia , Futebol/fisiologia , Adolescente , Composição Corporal/fisiologia , Criança , Feminino , Humanos , MasculinoRESUMO
This meta-analysis aims to determine the effects of regular swimming on bone mineral density (BMD) in young adults (18-30 years). A systematic search was performed in Pubmed, SPORTDiscus and the Cochrane Library from the earliest possible year to March 2016. Swimmers were compared to non-athletic controls (CG) and to high-impact athletes (HIGH). Effect sizes with the Hedges g in random effects models were developed. Fourteen studies met the inclusion criteria and were included in the meta-analyses. Swimmers presented similar BMD values to CG in whole-body (g = -0.20; P = 0.251), femoral neck (g = -0.05; P = 0.818) and lumbar spine (g = 0.18; P = 0.492); and lower BMD in the whole-body (g = -1.21; P < 0.001), femoral neck (g = -1.51; P < 0.001) and lumbar spine (g = -0.84; P = 0.017) than the HIGH. For the whole-body differences, the higher the latitude the smaller the differences between swimmers and HIGH (B = 0.10; P = 0.001). For the femoral neck differences, age also seemed to reduce the differences between groups (B = 0.19; P = 0.020). Young adult swimmers present similar BMD values than CG and lower values than HIGH.
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Densidade Óssea/fisiologia , Natação/fisiologia , Absorciometria de Fóton , Adolescente , Adulto , Fatores Etários , Colo do Fêmur/diagnóstico por imagem , Colo do Fêmur/fisiologia , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiologia , Adulto JovemRESUMO
OBJECTIVE: To investigate dietary sources of Ca and vitamin D (VitD) intakes, and the associated sociodemographic and lifestyle factors, among European adolescents. DESIGN: Linear regression mixed models were used to examine sex-specific associations of Ca and VitD intakes with parental education, family affluence (FAS), physical activity and television (TV) watching while controlling for age, Tanner stage, energy intake and diet quality. SETTING: The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA)Cross-Sectional Study. SUBJECTS: Adolescents aged 12·5-17·5 years (n 1804). RESULTS: Milk and cheese were the main sources of Ca (23 and 19 % contribution to overall Ca intake, respectively). Fish products were the main VitD source (30 % contribution to overall VitD intake). Ca intake was positively associated with maternal education (ß=56·41; 95 % CI 1·98, 110·82) and negatively associated with TV viewing in boys (ß=-0·43; 95 % CI -0·79, -0·07); however, the significance of these associations disappeared when adjusting for diet quality. In girls, Ca intake was positively associated with mother's (ß=73·08; 95 % CI 34·41, 111·74) and father's education (ß=43·29; 95 % CI 5·44, 81·14) and FAS (ß=37·45; 95 % CI 2·25, 72·65). This association between Ca intake and mother's education remained significant after further adjustment for diet quality (ß=41·66; 95 % CI 0·94, 82·38). Girls with high-educated mothers had higher Ca intake. CONCLUSIONS: Low-educated families with poor diet quality may be targeted when strategizing health promotion programmes to enhance dietary Ca.
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Comportamento do Adolescente , Cálcio da Dieta/administração & dosagem , Dieta , Estilo de Vida Saudável , Fatores Socioeconômicos , Vitamina D/administração & dosagem , Adolescente , Fenômenos Fisiológicos da Nutrição do Adolescente , Criança , Estudos Transversais , Laticínios , Europa (Continente) , Exercício Físico , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Avaliação Nutricional , Comportamento Sedentário , Inquéritos e Questionários , Televisão , População BrancaRESUMO
OBJECTIVE: To describe cortical and trabecular volumetric bone mineral density (vBMD), bone mineral content (BMC), cross-sectional area (CSA), and bone strength indexes (BSIs) in adolescent endurance-trained cyclists (CYC) and compare them with controls (CON). DESIGN: Descriptive cohort study. PARTICIPANTS: Twenty-five male adolescent CYC and 17 CON. ASSESSMENT OF RISK FACTORS: Peripheral quantitative computed tomography was used to evaluate proximal and distal sites of the radius and tibia. MAIN OUTCOME MEASURES: Total, trabecular, and cortical BMC, vBMD, and CSA were measured. Also, cortical thickness, endosteal and periosteal circumferences, and different BSIs were calculated. Unadjusted analysis of variance and body weight-adjusted analysis of covariance tests were applied between cyclist and control groups. RESULTS: Cyclists were almost 12% lighter than CON (P < 0.05). Unadjusted data showed lower distal total vBMD and proximal cortical BMC and vBMD in cyclists compared with CON at the radius (P < 0.05) and lower distal total and trabecular BMC, vBMD and bone area, proximal total and cortical BMC and vBMD, and cortical bone area at the tibia (P < 0.05). Body weight-adjusted data showed the same differences for distal total vBMD at the radius and total and trabecular BMC and vBMD at the tibia, diaphyseal radius cortical vBMD and tibia total vBMD, cortical BMC and area, and also for tibia cortical thickness and BSI. The rest of differences were no longer detectable and bone area at the distal radius become significantly higher in cyclist compared with CON (P < 0.05). CONCLUSIONS: Adolescent CYC in this study showed lower values of BMC and vBMD at determined sites of the radius and tibia than CON, some of these differences were explained in part by their lower body weight. However, even further adjustment, some differences remained, which indicates that further longitudinal studies are needed to better understand if cycling influences these differences.
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Ciclismo/fisiologia , Densidade Óssea , Rádio (Anatomia)/fisiologia , Tíbia/fisiologia , Adolescente , Análise de Variância , Peso Corporal , Estudos de Casos e Controles , Diáfises/fisiologia , Humanos , MasculinoRESUMO
The aim was to assess the relationship between school rhythm and physical activity (PA) in adolescents. The study included 2024 adolescents (12.5-17.4 years). Participants wore an accelerometer for 7 days. A short school rhythm was defined as a short time at school with short recesses and less time in teaching per day (Group 1). A long school rhythm was defined as a longer time at school with more time in teaching and recess (Group 2). Adolescents in Group 1 performed less moderate to vigorous PA (MVPA) than those in Group 2 per week (P < .0001), especially during school days (recess: 3.9 ± 4.0 vs. 9.8 ± 7.9 min · day-1; P < .0001; teaching hours: 14.5 ± 9.8 vs. 19.1 ± 12.0 min · day-1; P < .0001). Adolescents in Group 1 were less likely to meet the PA recommendations than were adolescents in Group 2: 30.7% vs. 34.1% (P < .0001). During school days, the percentage of adolescents who spent more than 2 h · day-1 in sedentary activities was greater in the Group 1 (P < .001). Our results suggest that leisure-time out-of-school hours is used mainly for sedentary activities, and that school time provides a good opportunity for promoting PA.
Assuntos
Comportamento do Adolescente/fisiologia , Exercício Físico , Instituições Acadêmicas , Actigrafia , Adolescente , Europa (Continente) , Feminino , Humanos , Masculino , Educação Física e Treinamento , Comportamento Sedentário , Fatores de TempoRESUMO
The aims of the present study were, firstly, to evaluate areal bone mineral density (aBMD), bone strength and structure during a swimming season and compare them to those of normo-active controls (CG), and secondly to ascertain whether practising an additional weight-bearing sport other than swimming might improve bone. Twenty-three swimmers who only swam (SWI-PURE; 14 males, 9 females), 11 swimmers who combined swimming with an additional weight-bearing sport (SWI-SPORT; 8 males, 3 females) and 28 controls (CG; 16 males, 12 females) participated in the present study. aBMD was assessed with dual energy X-ray (DXA). Bone mass, area, structure and strength of the non-dominant tibia and radius were measured with peripheral quantitative computed tomography (pQCT). Measurements were performed at the beginning of the swimming season and 8 months later. The only difference among groups for DXA and pQCT variables was found for arm aBMD, which was higher in the SWI-SPORT than in the CG group at both pre- and post-evaluation. Group by time interactions (GxT) were found for trochanter aBMD when comparing SWI-SPORT to CG and SWI-SPORT to SWI-PURE, favouring in both cases SWI-SPORT. No GxT were found for the radius. For the tibia, GxT were found between SWI-SPORT and CG and between SWI-PURE and CG, in both cases favouring the swimmers. A season of swimming does not confer any additional benefits to aBMD, but may confer minor benefits to structure and mass. Complementing swimming with a weight-bearing activity is beneficial to bone.
RESUMO
PURPOSE: In epidemiology, the relationship between increased adiposity and cancer risk has long been recognized. However, whether the association is the same for measures of abdominal or whole body adiposity is unclear. The aim of this systematic review is to compare cancer risk, associated with body mass index (BMI), an indicator of whole body adiposity, with indicators of abdominal adiposity in studies in which these indicators have been directly measured. METHODS: We conducted a systematic search from 1974 (EMBASE) and 1988 (PubMed) to September 2015 with keywords related to adiposity and cancer. Included studies were limited to cohort studies reporting directly measured anthropometry and performing mutually adjusted analyses. RESULTS: Thirteen articles were identified, with two reporting on breast cancer, three on colorectal cancer, three on endometrial cancer, two on gastro-oesophageal cancer, two on renal cancer, one on ovarian cancer, one on bladder cancer, one on liver and biliary tract cancer and one on leukaemia. Evidence suggests that abdominal adiposity is a stronger predictor than whole body adiposity for gastro-oesophageal, leukaemia and liver and biliary tract cancer in men and women and for renal cancer in women. Abdominal adiposity was a stronger predictor for bladder and colorectal cancer in women, while only BMI was a predictor in men. In contrast, BMI appears to be a stronger predictor for ovarian cancer. For breast and endometrial cancer, both measures were predictors for cancer risk in postmenopausal women. CONCLUSIONS: Only few studies used mutually adjusted and measured anthropometric indicators when studying adiposity-cancer associations. Further research investigating cancer risk and adiposity should include more accurate non-invasive indicators of body fat deposition and focus on the understudied cancer types, namely leukaemia, ovarian, bladder and liver and biliary tract cancer.
Assuntos
Adiposidade , Neoplasias/epidemiologia , Obesidade Abdominal/epidemiologia , Antropometria , Índice de Massa Corporal , Feminino , Humanos , Masculino , Neoplasias/patologia , Obesidade/epidemiologia , RiscoRESUMO
PURPOSE: The European "Healthy Lifestyle in Europe by Nutrition in Adolescence" (HELENA) project evaluated two different approaches to harmonize the matching procedures between 24-h recall data and food composition databases. In the first approach, the 24-h recall data were linked to the local/national food composition databases using standardized procedures, while in the second approach, the 24-h recall data were linked to the German BLS database which includes a larger food list. The aim of this paper was to compare the intakes of energy and eight nutrient components calculated via both approaches. METHODS: Two non-consecutive 24-h recalls were performed in 1268 adolescents. Energy, carbohydrates, proteins, fat, fiber, water, alcohol, calcium and vitamin C were calculated via the two approaches at individual level. Paired samples t test and Pearson's correlations were used to compare the mean intakes of energy and the eight mentioned nutrients and to investigate the possible associations between the two approaches. RESULTS: Small but significant differences were found between the intakes of energy and the eight food components when comparing both approaches. Very strong and strong correlations (0.70-0.95) were found between both methods for all nutrients. CONCLUSION: The dietary intakes obtained via the two different linking procedures are highly correlated for energy and the eight nutrients under study.