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1.
Brain Cogn ; 180: 106208, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39111187

RESUMO

This study aimed to evaluate whether cerebral oxygenation of the prefrontal cortex and associative-dissociative focus while completing the task mediate changes in cognition during exercise. Seventy-five young college-aged adults participated in this within-subjects randomized cross-over two-arm experimental design. During each session, participants completed a Stroop task four separate times: at baseline, two times during the exercise session, and at post-test. The experimental arm session involved participants cycling first at a moderate intensity, followed by cycling at a vigorous intensity. The active control arm session involved participants cycling at a very light intensity to ensure any effects were attributable to the level of exertion rather than the control of motor coordination. Cerebral oxygenation of the prefrontal cortex was assessed using fNIRS, while associate-dissociate attention was assessed using a self-report scale to provide insight into two hypothesized mechanisms which may contribute to alterations in cognition during exercise. Replicating well-established findings, results showed that during vigorous-intensity exercise, accuracy rates decreased for the most cognitively demanding conditions of the Stroop task, while reaction times were generally shorter compared to baseline. Neither shifting of attention in response to the dual-task nor prefrontal cortex oxygenation were observed to mediate cognitive deficits associated with vigorous exercise.

2.
Nutr Neurosci ; : 1-14, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38170169

RESUMO

Over recent decades, dietary patterns have changed significantly due to the increasing availability of convenient, ultra-processed refined foods. Refined foods are commonly depleted of key bioactive compounds, which have been associated with several deleterious health conditions. As the gut microbiome can influence the brain through a bidirectional communication system known as the 'microbiota-gut-brain axis', the consumption of refined foods has the potential to affect cognitive health. In this study, multi-omics approaches were employed to assess the effect of a refined diet on the microbiota-gut-brain axis, with a particular focus on bile acid metabolism. Mice maintained on a refined low-fat diet (rLFD), consisting of high sucrose, processed carbohydrates and low fibre content, for eight weeks displayed significant gut microbial dysbiosis, as indicated by diminished alpha diversity metrics (p < 0.05) and altered beta diversity (p < 0.05) when compared to mice receiving a chow diet. Changes in gut microbiota composition paralleled modulation of the metabolome, including a significant reduction in short-chain fatty acids (acetate, propionate and n-butyrate; p < 0.001) and alterations in bile acid concentrations. Interestingly, the rLFD led to dysregulated bile acid concentrations across both the colon (p < 0.05) and the brain (p < 0.05) which coincided with altered neuroinflammatory gene expression. In particular, the concentration of TCA, TDCA and T-α-MCA was inversely correlated with the expression of NF-κB1, a key transcription factor in neuroinflammation. Overall, our results suggest a novel link between a refined low-fat diet and detrimental neuronal processes, likely in part through modulation of the microbiota-gut-brain axis and bile acid dysmetabolism.

3.
J Sport Exerc Psychol ; 45(6): 337-346, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38061352

RESUMO

The aim of the present study was to examine the effects of attention-deficit/hyperactivity disorder (ADHD) -related psychostimulant use in the context of concussion risk and symptom recovery. Data were obtained from the National Collegiate Athletic Association Department of Defense Grand Alliance Concussion Assessment, Research, and Education (NCAA-DOD CARE) Consortium from 2014 to 2017. Relative to individuals without diagnosed ADHD (i.e., control), both ADHD diagnosis and the combination of ADHD diagnosis and psychostimulant use were associated with a greater risk of incurring a concussive injury. Following a concussive injury, ADHD diagnosis was associated with longer symptom recovery time relative to the control group. However, individuals with ADHD who use psychostimulants did not take longer to resolve symptoms than controls, suggesting that psychostimulants may have a positive influence on recovery. Regardless of time point, ADHD diagnosis was associated with an elevated number of concussion-related symptoms; however, this effect appears mitigated by having used ADHD-related psychostimulants.


Assuntos
Traumatismos em Atletas , Transtorno do Deficit de Atenção com Hiperatividade , Concussão Encefálica , Esportes , Humanos , Traumatismos em Atletas/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Concussão Encefálica/tratamento farmacológico , Concussão Encefálica/complicações , Concussão Encefálica/diagnóstico , Atletas
4.
FASEB J ; 35(5): e21583, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33891334

RESUMO

The impact of sex and menopausal status in Alzheimer's disease remains understudied despite increasing evidence of greater female risk, particularly in APOE4 carriers. Utilizing female APOE-TR mice maintained on a high-fat diet background we induced ovarian failure through repeated VCD injections, to mimic human menopause. At 12 months of age, recognition memory and spatial memory were assessed using object recognition, Y-maze spontaneous alternation, and Barnes maze. A VCD*genotype interaction reduced the recognition memory (P < .05), with APOE4 VCD-treated animals unable to distinguish between novel and familiar objects. APOE4 mice displayed an additional 37% and 12% reduction in Barnes (P < .01) and Y-maze (P < .01) performance, indicative of genotype-specific spatial memory impairment. Molecular analysis indicated both VCD and genotype-related deficits in synaptic plasticity with BDNF, Akt, mTOR, and ERK signaling compromised. Subsequent reductions in the transcription factors Creb1 and Atf4 were also evident. Furthermore, the VCD*genotype interaction specifically diminished Ephb2 expression, while Fos, and Cnr1 expression reduced as a consequence of APOE4 genotype. Brain DHA levels were 13% lower in VCD-treated animals independent of genotype. Consistent with this, we detected alterations in the expression of the DHA transporters Acsl6 and Fatp4. Our results indicate that the combination of ovarian failure and APOE4 leads to an exacerbation of cognitive and neurological deficits.


Assuntos
Apolipoproteína E4/fisiologia , Transtornos Cognitivos/patologia , Cicloexenos/toxicidade , Transtornos da Memória/patologia , Menopausa , Plasticidade Neuronal , Doenças Ovarianas/complicações , Compostos de Vinila/toxicidade , Animais , Apolipoproteína E3/fisiologia , Comportamento Animal , Carcinógenos/toxicidade , Transtornos Cognitivos/etiologia , Feminino , Transtornos da Memória/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças Ovarianas/induzido quimicamente , Doenças Ovarianas/patologia
5.
Int J Mol Sci ; 23(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35008980

RESUMO

The complete molecular mechanisms underlying the pathophysiology of Alzheimer's disease (AD) remain to be elucidated. Recently, microRNA-455-3p has been identified as a circulating biomarker of early AD, with increased expression in post-mortem brain tissue of AD patients. MicroRNA-455-3p also directly targets and down-regulates APP, with the overexpression of miR-455-3p suppressing its toxic effects. Here, we show that miR-455-3p expression decreases with age in the brains of wild-type mice. We generated a miR-455 null mouse utilising CRISPR-Cas9 to explore its function further. Loss of miR-455 resulted in increased weight gain, potentially indicative of metabolic disturbances. Furthermore, performance on the novel object recognition task diminished significantly in miR-455 null mice (p = 0.004), indicating deficits in recognition memory. A slight increase in anxiety was also captured on the open field test. BACE1 and TAU were identified as new direct targets for miR-455-3p, with overexpression of miR-455-3p leading to a reduction in the expression of APP, BACE1 and TAU in neuroblastoma cells. In the hippocampus of miR-455 null mice at 14 months of age, the levels of protein for APP, BACE1 and TAU were all increased. Such findings reinforce the involvement of miR-455 in AD progression and demonstrate its action on cognitive performance.


Assuntos
Doença de Alzheimer/etiologia , Ansiedade/genética , Transtornos da Memória/genética , MicroRNAs/genética , Fenótipo , Deleção de Sequência , Regiões 3' não Traduzidas , Fatores Etários , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Animais , Ácido Aspártico Endopeptidases/genética , Sequência de Bases , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Estudos de Associação Genética , Predisposição Genética para Doença , Camundongos , Camundongos Knockout , MicroRNAs/química , Interferência de RNA , Proteínas tau/genética
6.
J Sport Exerc Psychol ; 44(2): 116-126, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35213818

RESUMO

The aim of the present investigation was to provide insight into how postconcussion symptomatology may be altered in individuals exhibiting attention-deficit/hyperactivity disorder (ADHD)-related behaviors and examine factors that may be responsible for driving such relationships. A total of 99 individuals were assessed during the subacute phase of concussion recovery. Inattentive symptomatology, but not diagnosis of ADHD, was related to greater concussion-symptom severity and overall symptoms endorsed. Cluster and factor analyses highlighted that the relationship between ADHD symptomatology and concussion symptomatology was not a function of overlapping constructs being assessed (i.e., concussion-related symptomatology was not a proxy of ADHD-related symptomatology). These relationships were not mediated by parental observations of impairments in behaviors associated with executive functioning (i.e., executive dysfunction was not driving the greater concussion-related symptomatology associated with ADHD-related symptomatology). These findings highlight the importance of moving beyond categorical frameworks of ADHD to, instead, consider the continuum of underlying behaviors.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Cognição , Função Executiva , Análise Fatorial , Humanos , Autorrelato
7.
Metab Brain Dis ; 36(6): 1289-1303, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33856613

RESUMO

A growing number of investigations are exploring the utility of intranasal insulin as a means of mitigating cognitive decline. However, as a basic tenant of dementia prevention programs is increasing physical activity, it is essential to obtain a preliminary assessment of the safety profile of combining intranasal insulin with physical activity; to ensure that undue risks are not incurred. Utilizing a randomized double-blind placebo-controlled design, a sample of 116 non-diabetic, fasted college-aged adults were randomly assigned to receive a dose of 0-to-120 IU of NovoLog (Insulin Aspart) before being randomized to 20 min of exercise or sitting control condition. The safety of intranasal insulin was assessed by examining the incidence of potential symptoms of hypoglycemia and changes in peripheral blood glucose. The efficacy of a combination therapeutic approach was assessed using behavioral measures of inhibition and sustained attention alongside neuroelectric indices of attentional engagement. The frequency of symptoms reported following administration of intranasal insulin were not observed to interact with exercise so as to make their occurrence any more or less prominent, nor was the frequency observed to relate to the dose of intranasal insulin. However, doses of intranasal insulin of 100 IU or more were observed to result in a 7-fold increase in the likelihood of a level 1 hypoglycemic event for those individuals in the exercise condition. This study provides preliminary evidence to suggest that exercise is not associated with an increase in risk when combined with lower doses of intranasal insulin.Clinical trial registration The trial is registered at ClinicalTrials.gov, number NCT04292535.


Assuntos
Exercício Físico/fisiologia , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Insulina/efeitos adversos , Insulina/uso terapêutico , Administração Intranasal , Adolescente , Atenção/efeitos dos fármacos , Comportamento/efeitos dos fármacos , Glicemia/análise , Método Duplo-Cego , Feminino , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/administração & dosagem , Inibição Psicológica , Insulina/administração & dosagem , Masculino , Placebos , Adulto Jovem
8.
Scand J Med Sci Sports ; 30(9): 1777-1786, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32426888

RESUMO

OBJECTIVE: To determine how the dual-task nature of incorporating physical activity with instructional activities immediately impacts acuity of the approximate number system and on-task behavior in preschoolers. METHODS: Using a randomized within-participants repeated-measures crossover design, 51 children completed an approximate number system task before and after either 20-min of physically active instruction corresponding to 38% heart rate reserve (HRR; light-to-moderate intensity) or conventional sedentary instruction at corresponding to 21% HRR (very light intensity). RESULTS: Findings revealed that preschool-aged children exhibited similar learning and greater on-task behavior following a single bout of physically active instruction relative to conventional sedentary instruction. Overall, preschoolers accrued 931.3 ± 8.2 more steps and an additional 9 minutes at or above light-intensity activity during the physically active instruction. CONCLUSION: Accordingly, these findings suggest that the dual-task nature of physically active learning does not compromise learning, reduces the need for redirecting off-task behavior, and ultimately allows children to avoid sedentary behavior in educational contexts.


Assuntos
Atenção/fisiologia , Comportamento Infantil/fisiologia , Exercício Físico/fisiologia , Aprendizagem/fisiologia , Pré-Escolar , Estudos Cross-Over , Feminino , Humanos , Masculino
9.
J Sport Exerc Psychol ; 42(6): 472-479, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33176274

RESUMO

While compelling evidence indicates that poorer aerobic fitness relates to impairments in retrieving information from hippocampal-dependent memory, there is a paucity of research on how aerobic fitness relates to the acquisition of such relational information. Accordingly, the present investigation examined the association between aerobic fitness and the rate of encoding spatial relational memory-assessed using a maximal oxygen consumption test and a spatial configuration task-in a sample of 152 college-aged adults. The findings from this investigation revealed no association between aerobic fitness and the acquisition of spatial relational memory. These findings have implications for how aerobic fitness is characterized with regard to memory, such that aerobic fitness does not appear to relate to the rate of learning spatial-relational information; however, given previously reported evidence, aerobic fitness may be associated with a greater ability to recall relational information from memory.

10.
J Pediatr ; 208: 50-56.e1, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30902422

RESUMO

OBJECTIVE: To examine the associations of physical fitness and physical activity with executive function in children with overweight and obesity. STUDY DESIGN: A cross-sectional study involving 100 children with overweight and obesity (10.1 ± 1.1 years old; 58.0% boys). We assessed physical fitness components (ie, muscular strength, speed-agility, and cardiorespiratory fitness) using the ALPHA battery, and physical activity and sedentary time by accelerometry. Cognitive flexibility was measured by the Design Fluency Test and Trail Making Test, inhibition by the Stroop test, and planning ability by the Zoo Map Test. RESULTS: Handgrip strength was positively associated with planning ability (P = .025). Speed-agility was positively related to cognitive flexibility and inhibition (P < .05). Cardiorespiratory fitness and an overall fitness Z-score were positively associated with indicators of cognitive flexibility (P < .05). No associations were found for physical activity and sedentary time with executive function (P ≥ .05). CONCLUSIONS: Muscular strength, speed agility, and cardiorespiratory fitness are associated with executive function in children with overweight and obesity. Cognitive flexibility seems to be more robustly associated with all fitness components, whereas planning ability and inhibition might depend on the component analyzed. The positive associations found in the present study in children with overweight and obesity call for more exercise-based randomized controlled trials in this population.


Assuntos
Função Executiva , Exercício Físico , Obesidade Infantil/fisiopatologia , Obesidade Infantil/psicologia , Aptidão Física , Acelerometria , Aptidão Cardiorrespiratória , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Força Muscular
11.
Scand J Med Sci Sports ; 29(9): 1352-1363, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31058358

RESUMO

The aim of the present study was to examine the associations of physical fitness, sedentary time, and physical activity (PA) with working memory and neuroelectric activity in children with overweight/obesity. Seventy-nine children with overweight/obesity (10.2 ± 1.1 years old) participated in this cross-sectional study. We assessed physical fitness components (ie, muscular strength, speed agility, and cardiorespiratory fitness) using the ALPHA battery. Sedentary time and PA were assessed by GT3X+accelerometers (ActiGraph). Working memory was assessed using the delayed non-matched-to-sample task; mean reaction time (RT) and response accuracy were registered. Neuroelectric activity (ie, P3 amplitude and latency) was registered using the ActiveTwo System of BioSemi electroencephalogram. Higher upper-limb absolute strength was associated with lower response accuracy (P = 0.023), while higher lower-limb relative-to-weight strength was associated with larger P3 amplitude (P < 0.05). Higher speed agility and cardiorespiratory fitness levels were associated with shorter mean RT and larger P3 amplitude, and speed agility was also associated with shorter P3 latency (all P < 0.05). Vigorous PA was associated with larger P3 amplitude (P < 0.05). No associations were found for sedentary time or the rest of PA intensities (P ≥ 0.05). In addition to cardiorespiratory fitness, muscular strength and speed agility are also associated with working memory and neuroelectric activity in children with overweight/obesity. The association between PA and working memory is intensity-dependent, as significant findings were only observed for vigorous PA. Randomized controlled trials in this population would help to better understand whether improvements in different components of fitness and PA lead to better working memory and underlying brain function.


Assuntos
Aptidão Cardiorrespiratória , Exercício Físico , Memória de Curto Prazo , Força Muscular , Sobrepeso/fisiopatologia , Obesidade Infantil/fisiopatologia , Acelerometria , Criança , Estudos Transversais , Eletroencefalografia , Feminino , Humanos , Masculino , Tempo de Reação , Comportamento Sedentário
12.
Pediatr Exerc Sci ; 31(1): 1-27, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30760123

RESUMO

This commentary highlights 23 noteworthy publications from 2018, selected by leading scientists in pediatric exercise science. These publications have been deemed as significant or exciting in the field as they (a) reveal a new mechanism, (b) highlight a new measurement tool, (c) discuss a new concept or interpretation/application of an existing concept, or (d) describe a new therapeutic approach or clinical tool in youth. In some cases, findings in adults are highlighted, as they may have important implications in youth. The selected publications span the field of pediatric exercise science, specifically focusing on: aerobic exercise and training; neuromuscular physiology, exercise, and training; endocrinology and exercise; resistance training; physical activity and bone strength; growth, maturation, and exercise; physical activity and cognition; childhood obesity, physical activity, and exercise; pulmonary physiology or diseases, exercise, and training; immunology and exercise; cardiovascular physiology and disease; and physical activity, inactivity, and health.

13.
Int J Sport Nutr Exerc Metab ; 29(4): 406­410, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30507268

RESUMO

Research comparing portable body composition methods, such as bioelectrical impedance analysis (BIA), to air displacement plethysmography (ADP) is limited. We assessed reliability and validity of predicting fat-free mass (FFM) by the RJL, Omron, and Tanita BIA machines using ADP via BodPod as a criterion. FFM (kg) was assessed twice in college students (N = 77, 31 males and 46 females; age = 19.1 ± 1.2 years) using ADP, RJL, Omron, and Tanita BIAs. Reliability was assessed using analysis of variance to obtain an intraclass correlation statistic (Rxx). Validity was assessed using Pearson correlation (r) coefficient. FFM averaged 75.6 ± 9.4 kg in men and 59.8 ± 7.6 kg in women. Reliability was high in both genders RJL (Rxx = .974-.994), Omron (Rxx = .933-.993), and Tanita (Rxx = .921-.991). Validity within males was also high: RJL (r = .935), Omron (r = .942), and Tanita (r = .934), and only slightly lower in females: RJL (r = .924), Omron (r = .897), and Tanita (r = .898). The RJL, Omron, and Tanita BIA machines appear to be both reliable and valid for predicting FFM of male and female college students. Therefore, any of these three BIA devices is appropriate to use for body composition assessment in a healthy adult population.


Assuntos
Composição Corporal , Impedância Elétrica , Adolescente , Feminino , Humanos , Masculino , Pletismografia , Reprodutibilidade dos Testes , Adulto Jovem
14.
J Sport Exerc Psychol ; 41(2): 65-72, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31027460

RESUMO

This study was designed to examine the influence of performance feedback on task performance and neural activity in expert and novice baseball players. Participants completed a video task to determine whether thrown pitches were balls or strikes while their neural activity was recorded. After each pitch, participants were given feedback on the accuracy of their choice. Results indicated that college players exhibited larger frontocentral positivity amplitudes compared with novices, regardless of feedback type. Furthermore, results showed that the feedback-related negativity was related to response accuracy following incorrect feedback for college players, with larger feedback-related negativity amplitude associated with greater response accuracy. This relationship is independent of any relations between overall task accuracy and either feedback-related negativity amplitude or response accuracy following incorrect feedback. These results indicate that the nature of neural activity during pitch feedback for college baseball players can inform and influence participants' subsequent pitch-location performance.


Assuntos
Beisebol , Encéfalo/fisiologia , Retroalimentação , Desempenho Psicomotor , Autocontrole , Atletas , Eletroencefalografia , Humanos , Masculino , Adulto Jovem
15.
Neurobiol Dis ; 118: 40-54, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29940336

RESUMO

The antiepileptic drug ethosuximide has recently been shown to be neuroprotective in various Caenorhabditis elegans and rodent neurodegeneration models. It is therefore a promising repurposing candidate for the treatment of multiple neurodegenerative diseases. However, high concentrations of the drug are required for its protective effects in animal models, which may impact on its translational potential and impede the identification of its molecular mechanism of action. Therefore, we set out to develop more potent neuroprotective lead compounds based on ethosuximide as a starting scaffold. Chemoinformatic approaches were used to identify compounds with structural similarity to ethosuximide and to prioritise these based on good predicated blood-brain barrier permeability and C. elegans bioaccumulation properties. Selected compounds were initially screened for anti-convulsant activity in a C. elegans pentylenetetrazol-induced seizure assay, as a rapid primary readout of bioactivity; and then assessed for neuroprotective properties in a C. elegans TDP-43 proteinopathy model based on pan-neuronal expression of human A315T mutant TDP-43. The most potent compound screened, α-methyl-α-phenylsuccinimide (MPS), ameliorated the locomotion defects and extended the shortened lifespan of TDP-43 mutant worms. MPS also directly protected against neurodegeneration by reducing the number of neuronal breaks and cell body losses in GFP-labelled GABAergic motor neurons. Importantly, optimal neuroprotection was exhibited by external application of 50 µM MPS, compared to 8 mM for ethosuximide. This greater potency of MPS was not due to bioaccumulation to higher internal levels within the worm, based on 1H-nuclear magnetic resonance analysis. Like ethosuximide, the activity of MPS was abolished by mutation of the evolutionarily conserved FOXO transcription factor, daf-16, suggesting that both compounds act via the same neuroprotective pathway(s). In conclusion, we have revealed a novel neuroprotective activity of MPS that is >100-fold more potent than ethosuximide. This increased potency will facilitate future biochemical studies to identify the direct molecular target(s) of both compounds, as we have shown here that they share a common downstream DAF-16-dependent mechanism of action. Furthermore, MPS is the active metabolite of another approved antiepileptic drug, methsuximide. Therefore, methsuximide may have repurposing potential for treatment of TDP-43 proteinopathies and possibly other human neurodegenerative diseases.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Modelos Animais de Doenças , Succinimidas/uso terapêutico , Proteinopatias TDP-43/tratamento farmacológico , Proteinopatias TDP-43/genética , Animais , Animais Geneticamente Modificados , Anticonvulsivantes/química , Anticonvulsivantes/uso terapêutico , Caenorhabditis elegans , Feminino , Masculino , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Succinimidas/química , Proteinopatias TDP-43/patologia
16.
J Pediatr ; 187: 134-140.e3, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28622956

RESUMO

OBJECTIVES: To evaluate the effects of a 9-month physical activity intervention on changes in adiposity and cognitive control based on pretrial weight status (ie, healthy weight vs obese) in children. STUDY DESIGN: Participants included obese (n = 77) and matched healthy-weight (n = 77) preadolescents (8-9 years) who participated in a 9-month physical activity randomized controlled trial. Cognitive function was assessed with an inhibitory control task (modified flanker task). RESULTS: After the 9-month physical activity intervention, participants exhibited a reduction in adiposity. In contrast, children in the waitlist-control condition, particularly children identified as obese pretrial, gained visceral adipose tissue (P= .008). Changes in visceral adipose tissue were related to changes in cognitive performance, such that the degree of reduction in visceral adipose tissue directly related to greater gains in inhibitory control, particularly among obese intervention participants (CI -0.14, -0.04; P= .001). CONCLUSIONS: Participation in a daily physical activity program not only reduces adiposity but also improves children's cognitive function as demonstrated by an inhibitory control task. Furthermore, these findings reveal that the benefits of physical activity to improvements in cognitive function are particularly evident among children who are obese. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01334359 and NCT01619826.


Assuntos
Adiposidade/fisiologia , Cognição , Exercício Físico/fisiologia , Gordura Intra-Abdominal/fisiopatologia , Obesidade Infantil/fisiopatologia , Peso Corporal , Criança , Feminino , Humanos , Masculino , Redução de Peso
17.
Brain Cogn ; 113: 85-92, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28160688

RESUMO

Aerobic fitness has previously been related to cognitive control in preadolescents; however, these investigations have generally relied on global measures of performance. Thus, we have little understanding of how aerobic fitness may relate to trial-by-trial modulations in cognitive control. This study utilized congruency sequence effects (CSEs), which characterize how behavior on the current trial is influenced by the previous trial, to investigate the relation of aerobic fitness on varying levels of cognitive control. One hundred eighty-seven children completed tests of aerobic fitness and a flanker task. Regressions were performed to determine relationships between CSE sequences and aerobic fitness while controlling for other potential confounding factors (e.g., age, sex, IQ). Lower-fit children were less able to modulate cognitive control during sequences requiring relatively less cognitive control. Additionally, lower-fit children were less able to adjust for variable levels of cognitive control during relatively more difficult sequences. Lastly, lower-fit children had longer reaction times (RTs) for all sequences in the condition requiring greater amounts of cognitive control. These findings corroborate the importance of aerobic fitness for cognitive control in school-aged children, and extend the literature by demonstrating a relationship between fitness and trial-by-trial modulations in control demands.


Assuntos
Cognição/fisiologia , Aptidão Física/psicologia , Desempenho Psicomotor/fisiologia , Criança , Exercício Físico/psicologia , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia
18.
J Clin Child Adolesc Psychol ; 46(5): 646-652, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-26538120

RESUMO

We examined the relation between aerobic fitness and inhibition in young children with and without attention deficit hyperactivity disorder (ADHD)-risk status. Participants (91 ADHD risk, 107 typically developing, Mage = 6.83, 53.5% male, 68.2% Caucasian) completed an assessment of aerobic fitness and a flanker task requiring variable amounts of inhibitory control. Aerobic fitness was positively associated with inhibition. When inhibitory control demands were largest, the relation varied as a function of ADHD-risk status such that the link between aerobic fitness and inhibition was significant only for children with ADHD risk. The relation between aerobic fitness, status, and inhibition was further moderated by age for interference control. Specifically, the positive relation between aerobic fitness and interference control was only significant for younger children with ADHD risk. A fitness-cognition link appears in young childhood that seems particularly salient for those in the earliest school years with ADHD risk. The findings extend work on typically developing children and suggest that exploring aerobic fitness interventions to address executive function impairments in children at risk for ADHD is warranted.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Exercício Físico/fisiologia , Fatores Etários , Criança , Pré-Escolar , Feminino , Humanos , Inibição Psicológica , Masculino
19.
J Sport Exerc Psychol ; 39(2): 97-108, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28253050

RESUMO

Social exclusion can produce harmful affective and cognitive responses that undermine healthy functioning. Physical activity is known to have acute affective and cognitive effects that are adaptive and therefore may mitigate these responses. The purpose of this study was to assess walking as a strategy to reduce the effects of social exclusion on affect and working memory performance. Healthy female college students (N = 96, Mage = 19.2 ± 0.8 years) were randomly assigned to one of four experimental conditions: (a) sedentary plus neutral feedback, (b) sedentary plus exclusion feedback, (c) walking plus neutral feedback, or (d) walking plus exclusion feedback. Pre- and postactivity and pre- and postfeedback measures of affect and working memory performance were recorded. Excluded participants had a significant negative shift in affect following feedback, p < .05. Those who were sedentary prior to exclusion had lower affect scores following exclusion than the walking plus exclusion and neutral feedback conditions, p < .05. There were no direct effects of walking or social exclusion on working memory. However, perceptions of being ignored predicted smaller improvements in working memory performance for participants who were sedentary prior to exclusion, p < .05. The findings suggest that walking prior to social exclusion may mitigate the affective response to social exclusion as well as social perceptions that can undermine working memory. More broadly, this work supports continued examination of physical activity as a potential strategy for helping individuals cope with negative social experiences.


Assuntos
Afeto , Cognição , Distância Psicológica , Caminhada/psicologia , Feminino , Humanos , Memória de Curto Prazo , Percepção Social , Adulto Jovem
20.
Br J Nutr ; 116(9): 1537-1545, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27765078

RESUMO

Essential fatty acids (EFA) are PUFA that are metabolised to long-chain PUFA and are important for brain development and cognitive function. The objective of this study was to determine the association between whole-blood EFA and cognitive function in Tanzanian children. A total of 325 2-6-year-old children attempted the dimensional change card sort (DCCS) tasks to assess executive function. Blood samples were collected for fatty acid (FA) analysis by GC. Associations between executive function and FA levels were assessed by regression. Among the 130 4-6-year-old children who attempted the DCCS tasks, whole-blood levels of linoleic acid were positively associated with executive function, whereas whole-blood levels of α-linolenic acid and nervonic acid were inversely associated with executive function. A full model including all twenty-five FA explained 38 % of the variation in executive function, whereas a reduced model including only the EFA (α-linolenic acid and linoleic acid), DHA and EPA explained 25 % of the variation in executive function. Children who had sufficient whole-blood levels of EFA were 3·8 times more likely to successfully complete all DCCS tasks compared with children with insufficient EFA. These results suggest that whole-blood FA levels are associated with cognitive abilities. Intervention trials that include assessment of whole-blood FA levels are required to determine the relationships between intake, blood levels and executive function in Tanzanian children.


Assuntos
Desenvolvimento Infantil , Função Executiva , Ácidos Graxos Essenciais/sangue , Modelos Neurológicos , Neurogênese , Criança , Pré-Escolar , Estudos Transversais , Análise Fatorial , Ácidos Graxos Monoinsaturados/sangue , Feminino , Humanos , Modelos Lineares , Masculino , Análise de Regressão , Tanzânia , Ácido alfa-Linolênico/sangue
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