Now showing items 21-40 of 651

    • Exercise for overweight children and diabetes risk - Reply

      Davis, Catherine L.; Waller, Jennifer L.; Pollock, Norman K.; Augusta University (2013-01-09)
    • Oxidative stress and cardiovascular risk in overweight children in an exercise intervention program

      Dennis, B. Adam; Ergul, Adviye; Gower, Barbara A.; Allison, Jerry David; Davis, Catherine L.; Augusta University (2013-02-01)
      Background: This study aimed to determine whether oxidative stress was related to cardiovascular risk indices in children, and whether an exercise intervention would reduce oxidative stress. Methods: A randomized trial of two different doses of exercise and a no-exercise control group included 112 overweight and obese children, 7-11 years old. Plasma isoprostane levels were obtained at baseline and after the intervention. Cross-sectional analysis of oxidative stress and metabolic markers at baseline was performed. The effect of the exercise training on oxidative stress was tested. Results: Lower isoprostane levels were observed in blacks. At baseline, isoprostane was positively related to measures of fatness (BMI, waist circumference, percent body fat), insulin resistance and β-cell function (fasting insulin, insulin area under the curve, Matsuda index, disposition index, oral disposition index), and several lipid markers (low-density lipoprotein, triglycerides, total cholesterol), and inversely with fitness [peak oxygen consumption (VO2)], independent of race, sex, and cohort. No relation was found with visceral fat, blood pressure, or glycemia. Independent of percent body fat, isoprostane predicted triglycerides, β=0.23, total cholesterol-to-high-density lipoprotein (TC/HDL) ratio, β=0.23, and insulin resistance (insulin area under the curve, β=0.24, Matsuda index, β=-0.21, oral disposition index, β=0.33). Exercise did not reduce oxidative stress levels, despite reduced fatness and improved fitness in these children. Conclusions: Isoprostane levels were related to several markers of cardiovascular risk at baseline; however, despite reduced fatness and improved fitness, no effect of exercise was observed on isoprostane levels. To our knowledge, this is the first report in children to demonstrate a correlation of oxidative stress with disposition index, fitness, and TC/HDL ratio, the first to test the effect on oxidative stress of an exercise intervention that reduced body fat, and the first such exercise intervention study to include a substantial proportion of black children.
    • An 8-month randomized controlled exercise trial alters brain activation during cognitive tasks in overweight children

      Krafft, Cynthia E.; Schwarz, Nicolette F.; Chi, Lingxi; Weinberger, Abby L.; Schaeffer, David J.; Pierce, Jordan E.; Rodrigue, Amanda L.; Yanasak, Nathan Eugene; Miller, Patricia H.; Tomporowski, Phillip D.; et al. (2014-01)
      Objective Children who are less fit reportedly have lower performance on tests of cognitive control and differences in brain function. This study examined the effect of an exercise intervention on brain function during two cognitive control tasks in overweight children. Design and Methods Participants included 43 unfit, overweight (BMI ≥ 85th percentile) children 8- to 11-years old (91% Black), who were randomly divided into either an aerobic exercise (n = 24) or attention control group (n = 19). Each group was offered a separate instructor-led after-school program every school day for 8 months. Before and after the program, all children performed two cognitive control tasks during functional magnetic resonance imaging (fMRI): antisaccade and flanker. Results Compared to the control group, the exercise group decreased activation in several regions supporting antisaccade performance, including precentral gyrus and posterior parietal cortex, and increased activation in several regions supporting flanker performance, including anterior cingulate and superior frontal gyrus. Conclusions Exercise may differentially impact these two task conditions, or the paradigms in which cognitive control tasks were presented may be sensitive to distinct types of brain activation that show different effects of exercise. In sum, exercise appears to alter efficiency or flexible modulation of neural circuitry supporting cognitive control in overweight children.
    • An eight month randomized controlled exercise intervention alters resting state synchrony in overweight children

      Krafft, Cynthia E.; Pierce, Jordan E.; Schwarz, Nicolette F.; Chi, Lingxi; Weinberger, Abby L.; Schaeffer, David J.; Rodrigue, Amanda L.; Canchong, J.; Allison, Jerry David; Yanasak, Nathan Eugene; et al. (2014-01-03)
      Children with low aerobic fitness have altered brain function compared to higher-fit children. This study examined the effect of an 8-month exercise intervention on resting state synchrony. Twenty-two sedentary, overweight (body mass index ≥85th percentile) children 8-11. years old were randomly assigned to one of two after-school programs: aerobic exercise (n= 13) or sedentary attention control (n= 9). Before and after the 8-month programs, all subjects participated in resting state functional magnetic resonance imaging scans. Independent components analysis identified several networks, with four chosen for between-group analysis: salience, default mode, cognitive control, and motor networks. The default mode, cognitive control, and motor networks showed more spatial refinement over time in the exercise group compared to controls. The motor network showed increased synchrony in the exercise group with the right medial frontal gyrus compared to controls. Exercise behavior may enhance brain development in children.
    • Improved frontoparietal white matter integrity in overweight children is associated with attendance at an after-school exercise program

      Krafft, Cynthia E.; Schaeffer, David J.; Schwarz, Nicolette F.; Chi, Lingxi; Weinberger, Abby L.; Pierce, Jordan E.; Rodrigue, Amanda L.; Allison, Jerry David; Yanasak, Nathan Eugene; Liu, Tianming; et al. (2014-03)
      Aerobic fitness is associated with white matter integrity (WMI) in adults as measured by diffusion tensor imaging (DTI). This study examined the effect of an 8-month exercise intervention on WMI in children. Participants were 18 sedentary, overweight (BMI ≥85th percentile) 8- to 11-year-old children (94% Black), randomly assigned to either an aerobic exercise (n = 10) or sedentary attention control group (n = 8). Each group was offered an instructor-led after-school program every school day for approximately 8 months. Before and after the program, all subjects participated in DTI scans. Tractography was conducted to isolate the superior longitudinal fasciculus and investigate whether the exercise intervention affected WMI in this region. There was no group by time interaction for WMI in the superior longitudinal fasciculus. There was a group by time by attendance interaction, however, such that higher attendance at the exercise intervention, but not the control intervention, was associated with increased WMI. Heart rate and the total dose of exercise correlated with WMI changes in the exercise group. In the overall sample, increased WMI was associated with improved scores on a measure of attention and improved teacher ratings of executive function. This study indicates that participating in an exercise intervention improves WMI in children as compared to a sedentary after-school program.
    • Obesity elicits interleukin 1-mediated deficits in hippocampal synaptic plasticity

      Erion, Joanna R.; Wosiski-Kuhn, Marlena; Dey, Aditi; Hao, Shuai; Davis, Catherine L.; Pollock, Norman K.; Stranahan, Alexis M.; Augusta University (2014)
      Adipose tissue is a known source of proinflammatory cytokines in obese humans and animal models, including the db/db mouse, in which obesity arises as a result of leptin receptor insensitivity. Inflammatory cytokines induce cognitive deficits across numerous conditions, but no studies have determined whether obesity-induced inflammation mediates synaptic dysfunction. To address this question, we used a treadmill training paradigm in which mice were exposed to daily training sessions or an immobile belt, with motivation achieved by delivery of compressed air on noncompliance. Treadmill training prevented hippocampal microgliosis, abolished expression of microglial activation markers, and also blocked the functional sensitization observed in isolated cells after ex vivo exposure to lipopolysaccharide. Reduced microglial reactivity with exercise was associated with reinstatement of hippocampus-dependent memory, reversal of deficits in long-term potentiation, and normalization of hippocampal dendritic spine density. Because treadmill training evokes broad responses not limited to the immune system, we next assessed whether directly manipulating adiposity through lipectomy and fat transplantation influences inflammation, cognition, and synaptic plasticity. Lipectomy prevents and fat transplantation promotes systemic and central inflammation, with associated alterations in cognitive and synaptic function. Levels of interleukin 1β (IL1β) emerged as a correlate of adiposity and cognitive impairment across both the treadmill and lipectomy studies, so we manipulated hippocampal IL1 signaling using intrahippocampal delivery of IL1 receptor antagonist (IL1ra). Intrahippocampal IL1ra prevented synaptic dysfunction, proinflammatory priming, and cognitive impairment. This pattern supports a central role for IL1-mediated neuroinflammation as a mechanism for cognitive deficits in obesity and diabetes.
    • An 8-month exercise intervention alters frontotemporal white matter integrity in overweight children

      Schaeffer, David J.; Krafft, Cynthia E.; Schwarz, Nicolette F.; Chi, Lingxi; Rodrigue, Amanda L.; Pierce, Jordan E.; Allison, Jerry David; Yanasak, Nathan Eugene; Liu, Tianming; Davis, Catherine L.; et al. (2014-08)
      In childhood, excess adiposity and low fitness are linked to poor academic performance, lower cognitive function, and differences in brain structure. Identifying ways to mitigate obesity-related alterations is of current clinical importance. This study examined the effects of an 8-month exercise intervention on the uncinate fasciculus, a white matter fiber tract connecting frontal and temporal lobes. Participants consisted of 18 unfit, overweight 8- to 11-year-old children (94% Black) who were randomly assigned to either an aerobic exercise (n=10) or a sedentary control group (n=8). Before and after the intervention, all subjects participated in a diffusion tensor MRI scan. Tractography was conducted to isolate the uncinate fasciculus. The exercise group showed improved white matter integrity as compared to the control group. These findings are consistent with an emerging literature suggesting beneficial effects of exercise on white matter integrity.
    • The relationship between uncinate fasciculus white matter integrity and verbal memory proficiency in children

      Schaeffer, David J.; Krafft, Cynthia E.; Schwarz, Nicolette F.; Chi, Lingxi; Rodrigue, Amanda L.; Pierce, Jordan E.; Allison, Jerry David; Yanasak, Nathan Eugene; Liu, Tianming; Davis, Catherine L.; et al. (2014-08-20)
      During childhood, verbal learning and memory are important for academic performance. Recent functional MRI studies have reported on the functional correlates of verbal memory proficiency, but few have reported the underlying structural correlates. The present study sought to test the relationship between fronto-temporal white matter integrity and verbal memory proficiency in children. Diffusion weighted images were collected from 17 Black children (age 8-11 years) who also completed the California Verbal Learning Test. To index white matter integrity, fractional anisotropy values were calculated for bilateral uncinate fasciculus. The results revealed that low anisotropy values corresponded to poor verbal memory, whereas high anisotropy values corresponded to significantly better verbal memory scores. These findings suggest that a greater degree of myelination and cohesiveness of axonal fibers in uncinate fasciculus underlie better verbal memory proficiency in children.
    • Society of Behavioral Medicine position statement: elementary school-based physical activity supports academic achievement

      Buscemi, Joanna; Kong, Angela; Fitzgibbon, Marian L.; Bustamante, Eduardo E.; Davis, Catherine L.; Pate, Russell R.; Wilson, Dawn K.; Augusta University (2014-12)
      The Society of Behavioral Medicine (SBM) urges elementary schools to provide children with ample opportunities to engage in physical activity during school hours. In addition to promoting overall child health, physical activity also supports academic achievement. In addition to improving their aerobic fitness, regular physical activity improves cognitive function, influences the brain, and improves mood in children. Better aerobic fitness and physical activity are associated with increased grade point averages and standardized test scores. Despite the documented relationship between physical activity, fitness, and academic achievement, few schools have implemented physical activity as a tool to improve academic performance. SBM recommends that elementary schools provide children with the recommended 60 min of moderate-to-vigorous physical activity during school hours. Further, SBM urges schools to work with the local school districts and state education departments to mandate minimum physical activity time for elementary school physical education.
    • Endothelial health in childhood acute lymphoid leukemia survivors: Pilot evaluation with peripheral artery tonometry

      Ruble, Kathy; Davis, Catherine L.; Han, Hae Ra; Augusta University (2015-03-06)
      Background: Childhood cancer survivors are a growing population at risk for poor cardiac outcomes. Acute lymphoid leukemia (ALL) survivors are among those at increased risk of cardiovascular complications. Early identification of impaired vascular health may allow for interventions to improve these outcomes. The purpose of this study was to evaluate vascular health using peripheral artery tonometry in ALL survivors and compare results with healthy siblings. Procedure: Sixteen ALL survivor, healthy sibling pairs, aged 8 to 20 years, were evaluated for vascular health and cardiovascular risk factors (body mass index, central adiposity, blood pressure, and fitness). One-tailed paired t test was used to compare the groups. Results: Survivors were similar to siblings in cardiovascular risk measures but had poorer vascular health as measured by reactive hyperemia index (survivor RHI 1.54 vs. sibling 1.77; P=0.0474). Conclusion: This study reveals that even among survivors who are comparable to their healthy siblings in other traditional cardiovascular risks, there is evidence of poorer vascular health.
    • Liver enzymes and clustering cardiometabolic risk factors in European adolescents: The HELENA study

      Labayen, I; Ruiz, J.R.; Ortega, F.B.; Davis, Catherine L.; Rodriguez, G; Gonzalez-Gross, M.; Breidenassel, C.; Dallongeville, J.; Marcos, A.; Widhalm, K.; et al. (2015-10-01)
      Objectives This study aimed to explore the associations of liver biomarkers with cardiometabolic risk factors and their clustering, and to provide reference values (percentiles) and cut-off points for liver biomarkers associated with high cardiometabolic risk in European adolescents. Methods Alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), aspartate aminotransferase to ALT ratio (AST/ALT), waist circumference, blood pressure, triglycerides, high-density lipoprotein cholesterol and insulin were measured in 1084 adolescents. We computed a continuous cardiometabolic risk score and defined the high cardiometabolic risk. Results Higher ALT and GGT and lower AST/ALT were associated with adiposity and with the number of adverse cardiometabolic risk factors (Ps < 0.05). Higher GGT and lower AST/ALT were associated with higher cardiometabolic risk score (Ps < 0.001) in males and females, and ALT only in males (Ps < 0.001). Gender- and age-specific percentiles for liver biomarkers were provided. Receiver operating characteristic analyses showed a significant discriminatory accuracy of AST/ALT in identifying the low/high cardiometabolic risk (Ps < 0.01) and thresholds were provided. Conclusions Higher GGT and lower AST/ALT are associated with higher cardiometabolic risk factors and their clustering in male and female European adolescents, whereas the associations of ALT were gender dependent. Our results suggest the usefulness of AST/ALT as a screening test in the assessment of adolescents with high cardiometabolic risk and provide gender- and age-specific thresholds that might be of clinical interest.
    • Independent associations of organized physical activity and weight status with children's cognitive functioning: A matched-pairs design

      Davis, Catherine L.; Tkacz, Joseph P.; Tomporowski, Phillip D.; Bustamante, Eduardo E. (2015-11)
      Purpose: This study tested whether participation in organized physical activity (active vs. inactive) or weight status (normal weight vs. overweight or obese) independently relate to children's cognition, using a matchedpairs design. Design and Methods: Normal weight, active children (8-11 yrs, 5th-75th percentile BMI) were recruited from extracurricular physical activity programs while normal weight inactive (5th-75th percentile BMI) and overweight inactive children (BMI ≥85th percentile) were recruited from local Augusta, Georgia area schools. Measures included the Cognitive Assessment System, anthropometrics, and parent- and self-report of physical activity. Paired t tests compared cognition scores between matched groups of normal weight active vs. normal weight inactive (N = 24 pairs), normal weight inactive vs. overweight inactive (N = 21 pairs), and normal weight active vs. overweight inactive children (N = 16 pairs). Children in each comparison were matched for race, gender, age, and socioeconomic status. Results: Normal weight active children had higher Planning (M± SD = 109 ± 11 vs. 100 ± 11, p = .011) and Attention scores (108 ± 11 vs. 100 ± 11, p = .013) than overweight inactive children. Normal weight inactive children had higher Attention scores than overweight inactive children (105 ± 13 vs. 93 ± 12, p = .008). When compared with normal weight inactive children, normal weight active children had higher Planning (113 ± 10 vs. 102 ± 13, p = .008) and marginally higher Attention scores (111 ± 11 vs. 104 ± 12, p = .06). Conclusion: Findings suggest independent associations of children's weight status with selective attention, and physical activity with higher-order processes of executive function.
    • Antisaccade-related brain activation in children with attention-deficit/hyperactivity disorder - A pilot study

      Schwarz, Nicolette F.; Krafft, Cynthia E.; Chi, Lingxi; Weinberger, Abby L.; Schaeffer, David J; Pierce, Jordan E.; Rodrigue, Amanda L.; Williams, Celestine F; DiBattisto, Caroline H.; Maria, Bernard L.; et al. (2015-11-30)
      While antisaccade paradigms invoke circuitry associated with cognitive control and attention-deficit/hyperactivity disorder (ADHD), there is a dearth of functional magnetic resonance imaging (fMRI) investigations using antisaccade tasks among children with ADHD. Neural correlates associated with antisaccade performance were examined with fMRI in 11 children with ADHD (10 medicated) matched to 11 typically developing children. Significantly greater brain activation in regions in right dorsolateral prefrontal cortex and caudate nucleus was observed in children with ADHD relative to the control group. This pattern separated the children into their respective groups in a taxonomic manner. Sensitivity analyses probing comorbidity and medication-specific effects showed that results were consistent; however, the caudate nucleus difference was only detectable in the full sample, or in subsets with a more relaxed cluster threshold. Antisaccade performance did not significantly differ between the groups, perhaps as a result of greater brain activation or medication effects in the ADHD group. Thus, antisaccade paradigms may have sensitivity and specificity for the investigation of cognitive control deficits and associated neural correlates in ADHD, and may contribute towards the development of new treatment approaches for children with the disorder.
    • The Effect of Regular Exercise on Cognition in Special Populations of Children: Overweight and Attention-Deficit Hyperactivity Disorder

      Bustamante, Eduardo; Krafft, Cynthia E.; Schaeffer, David J; McDowell, Jennifer E.; Davis, Catherine L.; GEORGIA PREVENTION INSTITUTE (Elsevier, 2016-01-01)
      Childhood overweight/obesity and ADHD are common conditions of interest to researchers investigating the relationship between regular physical activity and children's cognition. Children in these populations are less physically active and have lower cognitive function than typically developing children. Research may identify the effects of regular exercise on cognition relevant to parents, clinicians, and educators struggling to respond to the growing needs presented by these conditions. Observational studies provide promising preliminary evidence of a relationship between regular exercise and cognition in these populations, but few rigorous randomized controlled trials have been conducted. Early results are encouraging. Future randomized trials promise to shed further light on the efficacy of different physical activity programs, elucidate neurobiological mechanisms that may guide refinement of interventions, and develop evidence-based interventions suitable for broad dissemination.
    • Passive Smoke Exposure and Its Effects on Cognition, Sleep, and Health Outcomes in Overweight and Obese Children

      Davis, Catherine L.; Tingen, Martha S.; Jia, Jenny; Sherman, Forrest; Williams, Celestine F; Bhavsar, Kruti; Wood, Nancy; Kobleur, Jessica; Waller, Jennifer L; GEORGIA PREVENTION INSTITUTE (2016-04-01)
      Background: Passive smoke exposure (PSE) may be a risk factor for childhood overweight and obesity and is associated with worse neurocognitive development, cognition, and sleep in children. The purpose of the study is to examine the effects of PSE on adiposity, cognition, and sleep in overweight and obese children using an objective measure of PSE. Methods: Overweight or obese children (n = 222) aged 7-11 (9.4 ± 1.1 years; 58% black; 58% female; 85% obese) were recruited from schools near Augusta, Georgia, over the course of the school year from 2003-2006 for a clinical trial, with data analyzed in 2009-2010. Passive smoke exposure was measured with plasma cotinine. Health, cognitive, and sleep measures and parent report of smoke exposure were obtained. Results: Overweight and obese children with PSE had greater overall and central adiposity than nonexposed overweight and obese children (p < 0.03). However, PSE was unrelated to prediabetes, insulin resistance, or visceral fat. PSE was linked to poorer cognitive scores (p < 0.04) independent of adiposity, but was not related to sleep-disordered breathing. Conclusions: PSE is associated with fatness and poorer cognition in children. Tailored interventions that target multiple health risk factors including nutrition, physical activity, and tobacco use in children and families are needed to prevent adverse health outcomes related to tobacco use and obesity.
    • Physical Activity Interventions for Neurocognitive and Academic Performance in Overweight and Obese Youth: A Systematic Review

      Bustamante, Eduardo; Williams, Celestine F; Davis, Catherine L.; GEORGIA PREVENTION INSTITUTE (Elsevier, 2016-06-01)
    • Randomized Controlled Trial of Exercise for ADHD and Disruptive Behavior Disorders

      Esteban Bustamante, Eduardo; Davis, Catherine L.; Frazier, Stacy L; Rusch, Dana; Fogg, Louis F.; Atkins, Marc S; Xavier Marquez, David; GEORGIA PREVENTION INSTITUTE (2016-07-01)
      Purpose The objective of this study is to test the feasibility and impact of a 10-wk after-school exercise program for children with attention deficit hyperactivity disorder and/or disruptive behavior disorders living in an urban poor community. Methods Children were randomized to an exercise program (n = 19) or a comparable but sedentary attention control program (n = 16). Cognitive and behavioral outcomes were collected pre-/posttest. Intent-To-Treat mixed models tested group-Time and group-Time-Attendance interactions. Effect sizes were calculated within and between groups. Results Feasibility was evidenced by 86% retention, 60% attendance, and average 75% maximum HR. Group-Time results were null on the primary outcome, parent-reported executive function. Among secondary outcomes, between-group effect sizes favored exercise on hyperactive symptoms (d = 0.47) and verbal working memory (d = 0.26), and controls on visuospatial working memory (d =-0.21) and oppositional defiant symptoms (d =-0.37). In each group, within-group effect sizes were moderate to large on most outcomes (d = 0.67 to 1.60). A group-Time-Attendance interaction emerged on visuospatial working memory (F[1,33] = 7.42, P < 0.05), such that attendance to the control program was related to greater improvements (r = 0.72, P < 0.01), whereas attendance to the exercise program was not (r = 0.25, P = 0.34). Conclusions Although between-group findings on the primary outcome, parent-reported executive function, were null, between-group effect sizes on hyperactivity and visuospatial working memory may reflect adaptations to the specific challenges presented by distinct formats. Both groups demonstrated substantial within-group improvements on clinically relevant outcomes. Findings underscore the importance of programmatic features, such as routines, engaging activities, behavior management strategies, and adult attention, and highlight the potential for after-school programs to benefit children with attention deficit hyperactivity disorder and disruptive behavior disorder living in urban poverty where health needs are high and services resources few.
    • Whole-body vibration mimics the metabolic effects of exercise in male leptin receptor-deficient mice

      McGee-Lawrence, Meghan E.; Wenger, Karl H.; Misra, Sudipta; Davis, Catherine L.; Pollock, Norman K.; Elsalanty, Mohammed; Ding, Kehong; Isales, C.M.; Hamrick, Mark W.; Wosiski-Kuhn, Marlena; et al. (Special Metabolism Section, 2017-05-01)
      Whole-body vibration (WBV) has gained attention as a potential exercise mimetic, but direct comparisons with the metabolic effects of exercise are scarce. To determine whether WBV recapitulates the metabolic and osteogenic effects of physical activity, we exposed male wild-type (WT) and leptin receptor-deficient (db/db) mice to daily treadmill exercise (TE) or WBVfor 3 months. Body weights were analyzed and compared with WT and db/db mice that remained sedentary. Glucose and insulin tolerance testing revealed comparable attenuation of hyperglycemia and insulin resistance in db/db mice following TE or WBV. Both interventions reduced body weight in db/ db mice and normalized muscle fiber diameter. TE orWBValso attenuated adipocyte hypertrophy in visceral adipose tissue and reduced hepatic lipid content in db/db mice. Although the effects of leptin receptor deficiency on cortical bone structure were not eliminated by either intervention, exercise and WBV increased circulating levels of osteocalcin in db/db mice. In the context of increased serum osteocalcin, the modest effects of TE and WBV on bone geometry, mineralization, and biomechanics may reflect subtle increases in osteoblast activity in multiple areas of the skeleton. Taken together, these observations indicate that WBV recapitulates the effects of exercise on metabolism in type 2 diabetes.
    • Prevention of diabetes in overweight/obese children through a family based intervention program including supervised exercise (PREDIKID project): Study protocol for a randomized controlled trial

      Arenaza, Lide; Medrano, María; Amasene, María; Rodríguez-Vigil, Beatriz; Díez, Ignacio; Graña, Manuel; Tobalina, Ignacio; Maiz, Edurne; Arteche, Edurne; Larrarte, Eider; et al. (2017-08-10)
      Background: The global pandemic of obesity has led to an increased risk for prediabetes and type-2 diabetes (T2D). The aims of the current project are: (1) to evaluate the effect of a 22-week family based intervention program, including supervised exercise, on insulin resistance syndrome (IRS) risk in children with a high risk of developing T2D and (2) to identify the profile of microRNA in circulating exosomes and in peripheral blood mononuclear cells in children with a high risk of developing T2D and its response to a multidisciplinary intervention program including exercise. Methods: A total of 84 children, aged 8-12 years, with a high risk of T2D will be included and randomly assigned to control (N=42) or intervention (N=42) groups. The control group will receive a family based lifestyle education and psycho-educational program (2 days/month), while the intervention group will attend the same lifestyle education and psycho-educational program plus the exercise program (3 days/week, 90 min per session including warm-up, moderate to vigorous aerobic activities, and strength exercises). The following measurements will be evaluated at baseline prior to randomization and after the intervention: fasting insulin, glucose and hemoglobin A1c; body composition (dual-energy X-ray absorptiometry); ectopic fat (magnetic resonance imaging); microRNA expression in circulating exosomes and in peripheral blood mononuclear cells (MiSeq; Illumina); cardiorespiratory fitness (cardiopulmonary exercise testing); dietary habits and physical activity (accelerometry). Discussion: Prevention and identification of children with a high risk of developing T2D could help to improve their cardiovascular health and to reduce the comorbidities associated with obesity. Trial registration: ClinicalTrials.gov, ID: NCT03027726. Registered on 16 January 2017.
    • A whole brain volumetric approach in overweight/obese children: Examining the association with different physical fitness components and academic performance. The ActiveBrains project

      Esteban-Cornejo, Irene; Cadenas-Sanchez, Cristina; Contreras-Rodriguez, Oren; Verdejo-Roman, Juan; Mora-Gonzalez, Jose; Migueles, Jairo H.; Henriksson, Pontus; Davis, Catherine L.; Verdejo-Garcia, Antonio; Catena, Andrés; et al. (Elsevier, 2017-10-01)
      Obesity, as compared to normal weight, is associated with detectable structural differences in the brain. To the best of our knowledge, no previous study has examined the association of physical fitness with gray matter volume in overweight/obese children using whole brain analyses. Thus, the aim of this study was to examine the association between the key components of physical fitness (i.e. cardiorespiratory fitness, speed-agility and muscular fitness) and brain structural volume, and to assess whether fitness-related changes in brain volumes are related to academic performance in overweight/obese children. A total of 101 overweight/obese children aged 8–11 years were recruited from Granada, Spain. The physical fitness components were assessed following the ALPHA health-related fitness test battery. T1-weighted images were acquired with a 3.0 T S Magnetom Tim Trio system. Gray matter tissue was calculated using Diffeomorphic Anatomical Registration Through Exponentiated Lie algebra (DARTEL). Academic performance was assessed by the Batería III Woodcock-Muñoz Tests of Achievement. All analyses were controlled for sex, peak high velocity offset, parent education, body mass index and total brain volume. The statistical threshold was calculated with AlphaSim and further Hayasaka adjusted to account for the non-isotropic smoothness of structural images. The main results showed that higher cardiorespiratory fitness was related to greater gray matter volumes (P < 0.001, k = 64) in 7 clusters with β ranging from 0.493 to 0.575; specifically in frontal regions (i.e. premotor cortex and supplementary motor cortex), subcortical regions (i.e. hippocampus and caudate), temporal regions (i.e. inferior temporal gyrus and parahippocampal gyrus) and calcarine cortex. Three of these regions (i.e. premotor cortex, supplementary motor cortex and hippocampus) were related to better academic performance (β ranging from 0.211 to 0.352; all P < 0.05). Higher speed-agility was associated with greater gray matter volumes (P < 0.001, k = 57) in 2 clusters (i.e. the inferior frontal gyrus and the superior temporal gyrus) with β ranging from 0.564 to 0.611. Both clusters were related to better academic performance (β ranging from 0.217 to 0.296; both P < 0.05). Muscular fitness was not independently associated with greater gray matter volume in any brain region. Furthermore, there were no statistically significant negative association between any component of physical fitness and gray matter volume in any region of the brain. In conclusion, cardiorespiratory fitness and speed-agility, but not muscular fitness, may independently be associated with greater volume of numerous cortical and subcortical brain structures; besides, some of these brain structures may be related to better academic performance. Importantly, the identified associations of fitness and gray matter volume were different for each fitness component. These findings suggest that increases in cardiorespiratory fitness and speed-agility may positively influence the development of distinctive brain regions and academic indicators, and thus counteract the harmful effect of overweight and obesity on brain structure during childhood.