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2.
PLoS One ; 16(7): e0253892, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34197518

RESUMO

INTRODUCTION: Osteoporosis and metabolic syndrome (MetS) are diseases that have serious public health consequences, reducing the quality of life of patients and increasing morbidity and mortality, with substantial healthcare expenditures. OBJECTIVE: To evaluate the impact of MetS on bone mineral density (BMD) and biochemical markers of bone formation and resorption in adolescents with excess weight. METHOD: A descriptive and analytical cross-sectional study was performed that evaluated 271 adolescents of both sexes (10 to 16 years). From the total sample, 42 adolescents with excess weight and the presence of MetS (14%) were selected. A further 42 adolescents with excess weight and without MetS were chosen, matched for chronological age, bone age, and pubertal developmental criteria to those with MetS, for each sex. Anthropometric measurements, blood pressure collection, and biochemical tests were performed in all adolescents, as well as evaluation of BMD and the bone biomarkers osteocalcin (OC), bone alkaline phosphatase (BAP), and carboxy-terminal telopeptide (S-CTx). RESULTS: The adolescents with excess weight and MetS exhibited significantly lower transformed BMD and concentrations of BAP, OC, and S-CTx compared to the matched group, except for OC in boys. A negative and significant correlation was observed between total body BMD and BAP (r = -0.55568; p = 0.005), OC (r = -0.81760; p = < .000), and S-CTx (r = -0.53838; p = 0.011) in girls. CONCLUSION: Metabolic syndrome may be associated with reduced bone mineral density and biochemical markers of bone formation and resorption in adolescents with excess weight.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Densidade Óssea/fisiologia , Remodelação Óssea , Síndrome Metabólica/complicações , Osteoporose/epidemiologia , Adolescente , Fosfatase Alcalina/sangue , Biomarcadores/sangue , Criança , Colágeno Tipo I/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/fisiopatologia , Osteocalcina/sangue , Osteoporose/sangue , Osteoporose/etiologia , Osteoporose/fisiopatologia , Peptídeos/sangue , Qualidade de Vida , Fatores de Risco
3.
Scand J Med Sci Sports ; 31(11): 2055-2063, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34275170

RESUMO

The stretch-shortening cycle (SSC) assists in effective force attenuation upon landing and augments force generation at take-off during a drop vertical jump (DVJ). General performance outcomes such as jump height or peak measures have been used to assess SSC function in youth populations; however, these discrete metrics fail to provide insight into temporal jump-landing characteristics. This study assessed DVJ force-time profiles in 1013 middle and high-school female athletes (n = 279 prepubertal, n = 401 pubertal, and n = 333 postpubertal). Maturity status was determined using the Pubertal Maturation Observation Scale. Ground reaction force data were analyzed to extract a range of variables to characterize force-time profiles. SSC function was categorized as poor, moderate, or good dependent on the presence of an impact peak and spring-like behavior. No differences in jump height or ground contact time were observed between maturity groups (p > 0.05). Significant differences in absolute peak landing and take-off force were evident between all maturational statuses (p < 0.05). Relative to bodyweight normalized forces, only peak take-off force was significantly different between prepubertal and postpubertal groups (p < 0.05; d = 0.22). Spring-like behavior showed small improvements from pubertal to postpubertal (p < 0.05; d = 0.25). Most females displayed poor SSC function at prepubertal (79.6%), pubertal (77.3%), and postpubertal (65.5%) stages of maturity. Large increases in absolute forces occur throughout maturation in female athletes; however, only small maturational differences were found in relative force or spring-like behavior. Consequently, most girls display poor SSC function irrespective of maturity.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Movimento/fisiologia , Exercício Pliométrico , Suporte de Carga/fisiologia , Adolescente , Traumatismos em Atletas/prevenção & controle , Fenômenos Biomecânicos , Criança , Feminino , Humanos
4.
Sci Rep ; 11(1): 12418, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127682

RESUMO

Extraction of environmental patterns underlies human learning throughout the lifespan and plays a crucial role not only in cognitive but also perceptual, motor, and social skills. At least two types of regularities contribute to acquiring skills: (1) statistical, probability-based regularities, and (2) serial order-based regularities. Memory performance of probability-based and/or serial order-based regularities over short periods (from minutes to weeks) has been widely investigated across the lifespan. However, long-term (months or year-long) memory performance of such knowledge has received relatively less attention and has not been assessed in children yet. Here, we aimed to test the long-term memory performance of probability-based and serial order-based regularities over a 1-year offline period in neurotypical children between the age of 9 and 15. Participants performed a visuomotor four-choice reaction time task designed to measure the acquisition of probability-based and serial order-based regularities simultaneously. Short-term consolidation effects were controlled by retesting their performance after a 5-h delay. They were then retested on the same task 1 year later without any practice between the sessions. Participants successfully acquired both probability-based and serial order-based regularities and retained both types of knowledge over the 1-year period. The successful retention was independent of age. Our study demonstrates that the representation of probability-based and serial order-based regularities remains stable over a long period of time. These findings offer indirect evidence for the developmental invariance model of skill consolidation.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Desenvolvimento Infantil/fisiologia , Aprendizagem/fisiologia , Memória de Longo Prazo/fisiologia , Adolescente , Atenção/fisiologia , Criança , Feminino , Humanos , Masculino , Destreza Motora/fisiologia , Tempo de Reação/fisiologia
5.
Nat Neurosci ; 24(8): 1176-1186, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34099922

RESUMO

The Adolescent Brain Cognitive Development (ABCD) Study® is a 10-year longitudinal study of children recruited at ages 9 and 10. A battery of neuroimaging tasks are administered biennially to track neurodevelopment and identify individual differences in brain function. This study reports activation patterns from functional MRI (fMRI) tasks completed at baseline, which were designed to measure cognitive impulse control with a stop signal task (SST; N = 5,547), reward anticipation and receipt with a monetary incentive delay (MID) task (N = 6,657) and working memory and emotion reactivity with an emotional N-back (EN-back) task (N = 6,009). Further, we report the spatial reproducibility of activation patterns by assessing between-group vertex/voxelwise correlations of blood oxygen level-dependent (BOLD) activation. Analyses reveal robust brain activations that are consistent with the published literature, vary across fMRI tasks/contrasts and slightly correlate with individual behavioral performance on the tasks. These results establish the preadolescent brain function baseline, guide interpretation of cross-sectional analyses and will enable the investigation of longitudinal changes during adolescent development.


Assuntos
Encéfalo/fisiologia , Adolescente , Desenvolvimento do Adolescente/fisiologia , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Valores de Referência
6.
J Sports Sci ; 39(20): 2353-2360, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34034625

RESUMO

The Motor Competence Assessment (MCA) is an innovative instrument to assess motor competence along the lifespan. The MCA model and normative values were recently established from the age of 3-to-23 years old. The purpose of this study was to validate MCA from early childhood to young adulthood.One thousand participants representing four age groups (3-6, 7-10, 11-16, 17-22 years) with 250 participants each, were assessed. Invariance of the MCA model along the age groups - configural, metric and structural - was tested using multigroup CFA.The MCA model showed to fit well all age groups. The multigroup unconstrained model showed a very good fit (NFI=0.99; TLI=0.99; CFI=0.99; RMSEA=0.03). A formal test for the invariance of loading coefficients returned a non-satisfactory goodness-of-fit adjustment and a significant difference with the unconstrained model (Δχ2 = 539.57; Δdf = 18; p= .00) . The structural invariance testing did not show formal invariance between factor correlations (Δχ2 = 73.04; Δdf = 9; p= .00) but the fit of the model was acceptable (above 0.96 and a RMSEA of 0.05), indicating that correlation values inter factors are stable.This study adds information for the validation of the MCA as a useful instrument for assessing motor competence throughout the life cycle.


Assuntos
Envelhecimento/fisiologia , Teste de Esforço , Destreza Motora , Adolescente , Desenvolvimento do Adolescente/fisiologia , Criança , Desenvolvimento Infantil/fisiologia , Pré-Escolar , Teste de Esforço/métodos , Humanos , Valores de Referência , Reprodutibilidade dos Testes , Adulto Jovem
7.
PLoS One ; 16(5): e0250984, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34010304

RESUMO

It is common knowledge that physical activity leads to physiological and psychological benefits. The current study explored the association between physical activity and self-regulation longitudinally and the indirect relationship this may have on academic achievement, using secondary data on primary and secondary school children from the Millennium Cohort Study, a cohort of infants born in 2000-2001 in the United Kingdom. There are two main findings. First, there is a positive link between physical activity and emotional (not behavioural) regulation both concurrently and longitudinally across all three time points, 7-years-old, 11-years-old and 14-years-old. The relationship was negative for emotional regulation and negligible for behavioural regulation when controlling for socioeconomic status. Second, across two time points (due to data availability), physical activity positively predicted academic achievement through emotional regulation for 7-year-olds and behavioural regulation in 11-year-olds. The impact of this relationship was more pronounced when controlling for socioeconomic status. Together these findings indicate that emotional regulation is linked to physical activity in early childhood. Subsequently, emotion regulation predicts academic attainment, suggesting that early interventions might focus on attention rather than behaviour.


Assuntos
Escolaridade , Exercício Físico/fisiologia , Exercício Físico/psicologia , Autocontrole/psicologia , Sucesso Acadêmico , Adolescente , Comportamento do Adolescente/fisiologia , Comportamento do Adolescente/psicologia , Desenvolvimento do Adolescente/fisiologia , Criança , Comportamento Infantil/fisiologia , Comportamento Infantil/psicologia , Desenvolvimento Infantil/fisiologia , Estudos de Coortes , Emoções , Feminino , Humanos , Estudos Longitudinais , Masculino , Classe Social , Reino Unido
8.
Neuroimage ; 237: 118134, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-33951508

RESUMO

Despite theoretical models suggesting developmental changes in neural substrates of cognitive control in adolescence, empirical research has rarely examined intraindividual changes in cognitive control-related brain activation using multi-wave multivariate longitudinal data. We used longitudinal repeated measures of brain activation and behavioral performance during the multi-source interference task (MSIT) from 167 adolescents (53% male) who were assessed annually over four years from ages 13 to 17 years. We applied latent growth modeling to delineate the pattern of brain activation changes over time and to examine longitudinal associations between brain activation and behavioral performance. We identified brain regions that showed differential change patterns: (1) the fronto-parietal regions that involved bilateral insula, bilateral middle frontal gyrus, left pre-supplementary motor area, left inferior parietal lobule, and right precuneus; and (2) the rostral anterior cingulate cortex (rACC) region. Longitudinal confirmatory factor analyses of the fronto-parietal regions revealed strong measurement invariance across time implying that multivariate functional magnetic resonance imaging data during cognitive control can be measured reliably over time. Latent basis growth models indicated that fronto-parietal activation decreased over time, whereas rACC activation increased over time. In addition, behavioral performance data, age-related improvement was indicated by a decreasing trajectory of intraindividual variability in response time across four years. Testing longitudinal brain-behavior associations using multivariate growth models revealed that better behavioral cognitive control was associated with lower fronto-parietal activation, but the change in behavioral performance was not related to the change in brain activation. The current findings suggest that reduced effects of cognitive interference indicated by fronto-parietal recruitment may be a marker of a maturing brain that underlies better cognitive control performance during adolescence.


Assuntos
Comportamento do Adolescente/fisiologia , Desenvolvimento do Adolescente/fisiologia , Córtex Cerebral/fisiologia , Função Executiva/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/crescimento & desenvolvimento , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Reprodutibilidade dos Testes
9.
J Pediatr ; 236: 194-203.e6, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33901518

RESUMO

OBJECTIVES: To investigate the association between gestational age, birthweight, and birthweight adjusted for gestational age, with domains of neurocognitive development and behavioral problems in adolescents in Tanzania. STUDY DESIGN: Data from a long-term follow-up of adolescents aged 11-15 years born to women previously enrolled in a randomized controlled trial of prenatal multiple micronutrient supplementation in Dar es Salaam, Tanzania, were used. A battery of neurodevelopmental tests were administered to measure adolescent general intelligence, executive function, and behavioral problems. The INTERGROWTH-21st newborn anthropometric standards were used to derive birthweight for gestational age z-scores. We assessed the shape of relationships using restricted cubic splines and estimated the associations of gestational age, birthweight, and birthweight for gestational age z-score with adolescent development using multivariable linear regressions. RESULTS: Among adolescents studied (n = 421), higher gestational age (per week), birthweight (per 100 grams), and birthweight for gestational age z-score (per SD) were linearly associated with higher intelligence score (adjusted standardized mean difference, 0.05 SD [95% CI, 0.01-0.09], 0.04 SD [95% CI, 0.02-0.06], and 0.09 SD [95% CI, 0.01-0.17], respectively). Birthweight and birthweight for gestational age z-score, but not gestational age, were also associated with improved executive function. Low birthweight (<2500 g) was associated with lower intelligence and executive function scores. Associations between birthweight and executive function were stronger among adolescents born to women with higher education. CONCLUSIONS: The duration of gestation and birthweight were positively associated with adolescent neurodevelopment in Tanzania. These findings suggest that interventions to improve birth outcomes may also benefit adolescent cognitive function.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Peso ao Nascer , Função Executiva/fisiologia , Idade Gestacional , Inteligência/fisiologia , Transtornos do Neurodesenvolvimento/epidemiologia , Adolescente , Criança , Estudos de Coortes , Feminino , Humanos , Modelos Lineares , Masculino , Transtornos do Neurodesenvolvimento/diagnóstico , Tanzânia
10.
Neurosci Lett ; 752: 135834, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33771578

RESUMO

Neurotrophic factors play an integral role in hippocampal plasticity, and interaction with HPA axis components, especially glucocorticoid receptors (GR), can mediate the structural and functional changes. In the present work, we investigated the long-term effects of combined exercise training (CET) and voluntary physical activity in an enriched environment (EE) in the pre-pubertal period on hippocampal neurotrophic factors and GR. For this purpose, a longitudinal study was designed. After three weeks, all rats were kept in the standard cages without any interventions until adulthood. Western blot analysis revealed a significant increase in hippocampal BDNF and VEGF protein levels in both EE and CET groups (P < 0.001), along with an increase in GR protein levels. In addition, EE decreased serum corticosterone levels compared to CET (P < 0.05). Serum insulin-like growth factor-1 (IGF-1) levels did not demonstrate remarkable changes between groups. Training interventions during sensitive developmental periods may produce profound and long-lasting effects on the hippocampus, at least in part by interactive effects of neurotrophic factors cascades and GR.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Hipocampo/crescimento & desenvolvimento , Condicionamento Físico Animal/fisiologia , Adolescente , Animais , Fator Neurotrófico Derivado do Encéfalo/análise , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Estudos Longitudinais , Masculino , Modelos Animais , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Receptores de Glucocorticoides/análise , Receptores de Glucocorticoides/metabolismo , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
J Sports Sci ; 39(14): 1615-1620, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33661083

RESUMO

The purpose of the current article was to use allometric models to identify the best body size descriptors and other anthropometric variables, body composition, and offset maturity that might be associated with the youngsters' 50m personal-best (PB) swim speeds (m·s-1). Eighty-five competitive swimmers (male, n=50; 13.5±1.8 y; female, n=35; 12.6±1.8 y) participated in this study. Height, body mass, sitting height, arm span, skinfolds, arm muscle area (AMA), and maturity offset were assessed. Swimming performance was taken as the PB time recorded in competition, and the propulsive force of their arm (PFA) was assessed by the tied swimming test. The multiplicative allometric model relating 50m PB swim speeds (m·s-1) to all the predictor variables found percentage body fat as a negative [(BF%) ß= -.121±.036; P=0.001], and PFA (PFA ß=.108±.033; P=0.001) and the girl's arm span (ß=.850±.301; P=0.006), all log-transformed, as positive significant predictors of log-transformed swim speed. The adjusted coefficient of determination, Radj2 was 54.8% with the log-transformed error ratio being 0.094 or 9.8%, having taken antilogs. The study revealed, using an allometric approach, that body fatness and PFA were significant contributors to 50m freestyle swim performance in young swimmers.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Desempenho Atlético/fisiologia , Composição Corporal/fisiologia , Tamanho Corporal/fisiologia , Desenvolvimento Infantil/fisiologia , Natação/fisiologia , Adolescente , Antropometria , Criança , Feminino , Humanos , Masculino
12.
J Clin Endocrinol Metab ; 106(6): 1668-1683, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33630047

RESUMO

CONTEXT: Epidemiologic studies have demonstrated that overweight/obese girls (OW/OB) undergo thelarche and menarche earlier than normal weight girls (NW). There have been no longitudinal studies to specifically investigate how body weight/fat affects both clinical and biochemical pubertal markers in girls. OBJECTIVE: To investigate the effect of total body fat on reproductive hormones and on the maturation of estrogen-sensitive tissues during puberty in girls. METHODS: Ninety girls (36 OW/OB, 54 NW), aged 8.2 to 14.7 years, completed 2.8 ±â€…1.7 study visits over 4 years. Visits included dual-energy x-ray absorptiometry to calculate total body fat (TBF), Tanner staging, breast ultrasound for morphological staging (BMORPH; A-E), pelvic ultrasound, hormone tests, and assessment of menarchal status. The effect of TBF on pubertal markers was determined using a mixed, multistate, or Cox proportional hazards model, controlling for baseline BMORPH. RESULTS: NW were older than OW/OB (11.3 vs 10.2 years, P < .01) at baseline and had more advanced BMORPH (P < .01). Luteinizing hormone, estradiol, and ovarian and uterine volumes increased with time with no effect of TBF. There was a time × TBF interaction for follicle-stimulating hormone, inhibin B, estrone, total and free testosterone, and androstenedione: Levels were initially similar, but after 1 year, levels increased in girls with higher TBF, plateaued in girls with midrange TBF, and decreased in girls with lower TBF. Girls with higher TBF progressed through BMORPH stage D more slowly but achieved menarche earlier than girls with lower TBF. CONCLUSION: In late puberty, girls with higher TBF demonstrate differences in standard hormonal and clinical markers of puberty. Investigation of the underlying causes and clinical consequences of these differences in girls with higher TBF deserves further study.


Assuntos
Tecido Adiposo/fisiologia , Composição Corporal/fisiologia , Puberdade/fisiologia , Absorciometria de Fóton , Adolescente , Desenvolvimento do Adolescente/fisiologia , Criança , Feminino , Humanos , Estudos Longitudinais , Menarca/fisiologia , Obesidade/metabolismo , Obesidade/fisiopatologia , Sobrepeso/metabolismo , Sobrepeso/fisiopatologia , Estados Unidos/epidemiologia
13.
J Sports Sci ; 39(14): 1585-1593, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33583340

RESUMO

This study aimed to investigate the influence of chronological age and maturation status on sprint acceleration characteristics in junior Australian football (AF) players. Biological maturity of 109 subjects was assessed and subjects were grouped according to predicted years from peak height velocity (PHV) (pre-, mid-, and post-PHV) and chronological age (13 years, 14 years, and 15 years). A one-way multivariate analysis of variance and magnitude-based decisions were used to determine between-group differences. Instantaneous velocity was measured during two maximal 30m sprints via radar gun with the velocity-time data used to derive the force, velocity, and power characteristics. Chronologically, the greatest differences were observed between the 13 and 14 year old groups with the latter group producing likely greater relative maximum power (Pmax) (ES[effect size]=0.44) and theoretical maximal velocity (V0) (ES=0.49). The post-PHV group likely demonstrated a greater ability to apply force at faster velocity (V0; ES=0.59) and orient the force in a horizontal direction (Drf%; ES=-0.49) than the mid-PHV group. No differences in relative theoretical maximal force (F0) were observed between groups. Considering the findings, practitioners should aim to improve relative lower limb strength through heavy sled push or sled pulls and traditional strength training exercises to improve relative F0.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Desempenho Atlético/fisiologia , Futebol Americano/fisiologia , Corrida/fisiologia , Aceleração , Adolescente , Fatores Etários , Austrália , Fenômenos Biomecânicos , Humanos , Cinética
14.
Sci Rep ; 11(1): 2908, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536524

RESUMO

Microcephaly and macrocephaly can be considered both cranial growth defects and clinical symptoms. There are two assessment criteria: one applied in dysmorphology and another conventionally used in clinical practice. The determination of which definition or under which paradigm the terminology should be applied can vary on a daily basis and from case to case as necessity dictates, as can defining the relationship between microcephaly or macrocephaly and syndromes or diseases associated with neurodysfunction. Thus, there is a need for standardization of the definition of microcephaly and macrocephaly. This study was designed to investigate associations between abnormal cranial development (head size) and diseases or syndromes linked to neurodysfunction based on essential data collected upon admission of patients to the Neurological Rehabilitation Ward for Children and Adolescents in Poland. The retrospective analysis involved 327 children and adolescents with medical conditions associated with neurodysfunction. Two assessment criteria were applied to identify subgroups of patients with microcephaly, normal head size, and macrocephaly: one system commonly used in clinical practice and another applied in dysmorphology. Based on the results, children and adolescents with syndromes or diseases associated with neurodysfunction present abnormal cranial development (head size), and microcephaly rarely co-occurs with neuromuscular disease. Macrocephaly frequently co-occurs with neural tube defects or neuromuscular diseases and rarely with cerebral palsy (p < 0.05); microcephaly frequently co-occurs with epilepsy and hypothyroidism (p < 0.001). Traditional classification facilitates the identification of a greater number of relationships and is therefore recommended for use in daily practice. There is a need to standardize the definition of microcephaly and macrocephaly and to include them in 'Human Phenotype Ontology' terms.


Assuntos
Cefalometria/normas , Megalencefalia/diagnóstico , Microcefalia/diagnóstico , Doenças do Sistema Nervoso/complicações , Crânio/crescimento & desenvolvimento , Adolescente , Desenvolvimento do Adolescente/fisiologia , Criança , Desenvolvimento Infantil/fisiologia , Pré-Escolar , Feminino , Humanos , Masculino , Megalencefalia/etiologia , Megalencefalia/fisiopatologia , Microcefalia/etiologia , Microcefalia/fisiopatologia , Doenças do Sistema Nervoso/fisiopatologia , Polônia , Estudos Retrospectivos , Síndrome
15.
J Sport Rehabil ; 30(5): 717-724, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33465761

RESUMO

CONTEXT: Badminton continues to be a highly competitive sport where training is introduced at an early age and load has intensified. This exposes players to a greater risk of injuries, in particular when assessing related training outcomes such as strength, agonist-antagonist ratio, and bilateral deficit among adolescents where age- and sex-associated growth and development should be considered. OBJECTIVE: To evaluate strength profile of the upper and lower limbs among adolescent elite Malaysian badminton players. DESIGN: Cross-sectional study. SETTING: Laboratory. PARTICIPANTS: Forty-eight asymptomatic athletes (24 males and 24 females) were grouped into early and late adolescence (13-14 y old and 15-17 y old, respectively). MAIN OUTCOME MEASURE(S): Strength (absolute and normalized) of the external/internal rotators of the shoulder and flexor/extensor of the knee and strength derivatives, conventional strength ratio (CSR), dynamic control ratio (DCR), and bilateral deficits were measured. RESULTS: Males showed greater strength in all strength indices (P < .05). The older group had greater strength compared to younger for most of the upper and lower limb indices (P < .05); these effects diminished when using normalized data. For females, there was no age group effect in the shoulder and knee strength. All players displayed lower shoulder and knee normative values for CSR and DCR. Dominant and non-dominant knee strength were comparable between sex and age groups. CONCLUSIONS: For males, growth and maturation had a greater contribution to strength gained compared to training, whereas for females, growth, maturation, and training did not improve strength. The normalized data indicated that training did not improve all indices measured apart from external rotator strength in females. All players also displayed lower normative values of CSR and DCR. These results suggest that training in elite adolescent Malaysian badminton players lacks consideration of strength gain and injury risk factors.


Assuntos
Articulação do Joelho/fisiologia , Força Muscular/fisiologia , Esportes com Raquete/fisiologia , Articulação do Ombro/fisiologia , Adolescente , Desenvolvimento do Adolescente/fisiologia , Fatores Etários , Atletas , Estudos Transversais , Feminino , Lateralidade Funcional/fisiologia , Humanos , Malásia , Masculino , Músculo Esquelético/fisiologia , Condicionamento Físico Humano/fisiologia , Manguito Rotador/fisiologia , Fatores Sexuais , Torque
16.
Neuroimage ; 229: 117784, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33503482

RESUMO

While it is well understood that the brain experiences changes across short-term experience/learning and long-term development, it is unclear how these two mechanisms interact to produce developmental outcomes. Here we test an interactive model of learning and development where certain learning-related changes are constrained by developmental changes in the brain against an alternative development-as-practice model where outcomes are determined primarily by the accumulation of experience regardless of age. Participants (8-29 years) participated in a three-wave, accelerated longitudinal study during which they completed a feedback learning task during an fMRI scan. Adopting a novel longitudinal modeling approach, we probed the unique and moderated effects of learning, experience, and development simultaneously on behavioral performance and network modularity during the task. We found nonlinear patterns of development for both behavior and brain, and that greater experience supported increased learning and network modularity relative to naïve subjects. We also found changing brain-behavior relationships across adolescent development, where heightened network modularity predicted improved learning, but only following the transition from adolescence to young adulthood. These results present compelling support for an interactive view of experience and development, where changes in the brain impact behavior in context-specific fashion based on developmental goals.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Encéfalo/crescimento & desenvolvimento , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/crescimento & desenvolvimento , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Rede Nervosa/diagnóstico por imagem , Estimulação Luminosa/métodos , Adulto Jovem
17.
Eur J Sport Sci ; 21(2): 231-239, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32079494

RESUMO

Most of the information gathered about physical fitness of paediatric populations are cross-sectional, resulting in normative perspectives that account for average values relative to age, but not to a comprehensive understanding of developmental individual trajectories. The aim of this study was to model the longitudinal development of cardiorespiratory fitness of boys and girls from 6 to 15 years of age, using an individual centred approach. Two hundred twenty-nine school children (128 boys; 101 girls) were followed on their 20 metres shuttle run test (20mSRT) results from 6 to 15 years of age. Annual measurements were made during the four years of primary school, and again at grade 9th or 10th. Individual trajectories of 20mSRT development were modelled and grouped according to their similarities of change in three different developmental pathways that were included in subsequent hierarchical nested models for testing each sex developmental model of cardiorespiratory fitness. Final models including the developmental pathways showed better deviance statistics (p < .001). Interindividual slope variances were almost zero, and statistically non-significant (0.05 boys 0.01 girls; p > .50), meaning these models capture well the existing variability, in respect to the rate of change. Individual pathways of change in the performance of 20mSRT test can be detected in childhood and adolescence. Additionally, all individual's developmental trajectories in 20mSRT can be described using three significantly different slopes. These pathways are indicative of a high, average, or low rate of change in performance over the years and differ from the normative approach.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Desenvolvimento Infantil/fisiologia , Corrida/fisiologia , Adolescente , Fatores Etários , Criança , Teste de Esforço , Feminino , Humanos , Estudos Longitudinais , Masculino
18.
Dev Med Child Neurol ; 63(1): 29-46, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32149404

RESUMO

AIM: (1) To systematically review the literature on developmental outcomes from infancy to adolescence of children with complex congenital heart disease (CHD) who underwent early surgery; (2) to run a meta-regression analysis on the Bayley Scales of Infant Development, Second Edition Mental Developmental Index and Psychomotor Developmental Index (PDI) of infants up to 24 months and IQs of preschool-aged children to adolescents; (3) to assess associations between perioperative risk factors and outcomes. METHOD: We searched pertinent literature (January 1990 to January 2019) in PubMed, Embase, CINAHL, and PsycINFO. Selection criteria included infants with complex CHD who had primary surgery within the first 9 weeks of life. Methodological quality, including risk of bias and internal validity, were assessed. RESULTS: In total, 185 papers met the inclusion criteria; the 100 with high to moderate methodological quality were analysed in detail. Substantial heterogeneity in the group with CHD and in methodology existed. The outcome of infants with single-ventricle CHD was inferior to those with two-ventricle CHD (respectively: average scores for PDI 77 and 88; intelligence scores 92 and 98). Perioperative risk factors were inconsistently associated with developmental outcomes. INTERPRETATION: The literature on children undergoing surgery in early infancy suggests that infants with a single ventricle are at highest risk of adverse developmental outcomes.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Procedimentos Cirúrgicos Cardíacos/estatística & dados numéricos , Desenvolvimento Infantil/fisiologia , Cardiopatias Congênitas/cirurgia , Inteligência , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Desempenho Psicomotor , Adolescente , Criança , Pré-Escolar , Cardiopatias Congênitas/patologia , Humanos , Lactente , Inteligência/fisiologia , Desempenho Psicomotor/fisiologia
19.
Am J Phys Anthropol ; 174(3): 463-478, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33105032

RESUMO

OBJECTIVES: The objective of this study is to apply pubertal stage estimation methods to a sample from a rural community: the post-medieval Dutch skeletal collection from Middenbeemster. Puberty is a key developmental period involving transition to physical adulthood with broad societal relevance through its impact on fertility, morbidity, and mortality. MATERIALS AND METHODS: Individuals (n = 55), including 27 of known sex and age-at-death, between the ages of 8 and 25 years were assessed for six skeletal markers indicative of pubertal growth spurt. Recent novel osteoarchaeological methods from Shapland and Lewis are used to reconstruct the timing and duration of pubertal stages. RESULTS: Pubertal acceleration occurred earlier in females (10.38 years, n = 8) than males (13.30 years, n = 6), whereas maturation occurred later in males (21.36 years, n = 11) than females (19.30 years, n = 5). Onset appears earlier and completion later compared to other archaeological skeletal samples with osteoarchaeological evidence of puberty. Age shortly after menarche was reconstructed at 20.45 years, substantially later than historic records and bioarchaeological research reports suggest. CONCLUSION: This early onset and late completion caused a "stretch" of the overall duration of puberty compared to other collections, especially of the last three stages. This prolonged development is reflected in historically known social expectations for the Netherlands, for example, that marriage and children should not occur before about 22-23 years of age. Increasing the range of past peoples with puberty stage reconstruction will permit more insightful interpretations of the biological and cultural patterns of this important life stage.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Osso e Ossos/anatomia & histologia , População Rural/história , Adolescente , Adulto , Determinação da Idade pelo Esqueleto , Antropologia Física , Cemitérios/história , Criança , Feminino , História do Século XIX , Humanos , Masculino , Países Baixos , Adulto Jovem
20.
Psychophysiology ; 58(1): e13694, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33040361

RESUMO

Prominent theory suggests that factor one psychopathic traits may develop from increased input from hormones in the hypothalamic pituitary gonadal axis (HPG; i.e., testosterone) and decreased input from the hypothalamic pituitary adrenal axis (HPA; i.e., cortisol). Although there are extensive findings connecting low cortisol to psychopathy, less support has emerged for high levels of testosterone. This study examined whether incorporating the HPG hormone, estradiol, into this model would reveal relationships in line with theory: high levels of estradiol and testosterone in combination with low levels of cortisol would inform psychopathic traits. Baseline and reactive hormone levels were measured and compared to Psychopathy Checklist-Youth Version (PCL-YV) interviews among 66 male justice-involved youth (M age = 15.73) in a Southeastern juvenile detention center. The primary findings of this study were relationships between interacting HPA and HPG axis hormones with facet one and facet two psychopathic traits. Specifically, psychopathy total scores, interpersonal traits, and affective traits related to estradiol and testosterone reactivity, in that psychopathy scores were more likely with decreases in hormone reactivity (i.e., change in hormone level) following a stressor. Moreover, affective traits related to reactivity in all three hormones. These findings support inclusion of estradiol in neurobiological models of psychopathy and consideration of the individual components of psychopathy. This study adds to the growing body of research supporting interactions between variations in functioning of the HPA and HPG axes in relation to psychopathy.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Transtorno da Conduta/metabolismo , Transtorno da Conduta/fisiopatologia , Estradiol/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Delinquência Juvenil , Adolescente , Sintomas Afetivos/etiologia , Sintomas Afetivos/metabolismo , Sintomas Afetivos/fisiopatologia , Transtorno da Conduta/complicações , Humanos , Hidrocortisona/metabolismo , Relações Interpessoais , Masculino , Saliva/metabolismo , Testosterona/metabolismo
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