V. The differential association of adiposity and fitness with cognitive control in preadolescent children

Associations between physical fitness and executive functions in 10-13 year male children in Saudi Arabia

Objectives

The aim of the present study was investigating the associations between physical fitness and executive function tasks in children aged 10-13 years, with a particular focus on the contribution of physical fitness to working memory.

Findings

The findings reported significant correlations between the N-Back task (a measure of working memory) and all three physical fitness tasks: grip strength, long jump, and shuttle run. Additionally, the Flanker task (assessing selective attention) was correlated only with the shuttle run task. However, no significant correlation was found between the Stroop task (measuring inhibition control) and the physical fitness tests. Regression analyses further demonstrated that physical fitness tasks significantly contributed to working memory performance, independent of age and BMI.

Contributions

These findings emphasize the importance of incorporating diverse physical activities in children's routines to support both physical and cognitive development, particularly in enhancing working memory, which is critical for academic achievement. From an educational and policy standpoint, integrating targeted fitness programs into school curricula may foster both physical health and cognitive development. Consequently, this study underscores the need for holistic approaches that combine physical and cognitive interventions, ultimately enhancing overall development and academic performance in schoolchildren. Hence, this study underscores the need for holistic educational interventions that integrate physical fitness with cognitive development.

Isotemporal substitution of accelerometer-derived sedentary behavior and physical activity on physical fitness in young children

This study investigates the effects of different types of physical activity (PA) on the physical fitness (PF) of young children in Japan, with a particular focus on how substituting sedentary behavior (SB) with active behaviors influences PF. We conducted a cross-sectional analysis of 1843 participants aged 3-6 years from northeastern Japan. Using triaxial accelerometers, we quantified PA, and PF was assessed via standardized tests. The innovative application of isotemporal substitution modeling (ISM) allowed us to analyze the impact of reallocating time from SB to more active states, specifically moderate-to-vigorous physical activity (MVPA) and light physical activity (LPA). Our findings reveal a robust association between increased MVPA and enhanced PF outcomes, underscoring the health benefits of reducing SB. Notably, replacing SB with LPA also showed beneficial effects on certain PF metrics, indicating LPA's potential role in early childhood fitness. These results highlight the critical importance of promoting MVPA and minimizing sedentary periods to bolster PF in young children. The study offers vital insights for shaping public health policies and emphasizes the need to cultivate an active lifestyle from an early age to secure long-term health advantages.

Weight status impacts children's incidental statistical learning

The expanding literature investigating the cognitive effects of childhood weight status has not included examinations of incidental statistical learning, the process by which children unintentionally acquire knowledge about patterns in their environments, despite evidence that it underlies many higher-level information processing capabilities. In the present study, we measured event-related potentials (ERPs) while school-aged participants completed a variation of an oddball task in which stimuli predicted the appearance of a target. Children were asked to respond to the target but were not given any information about the existence of predictive dependencies. We found that children with a healthy weight status had larger P3 amplitudes in response to the predictors that were most meaningful in completing the task, a finding that may suggest optimized learning mechanisms influenced by weight status. These findings offer an important first step to understanding how healthy lifestyle factors may influence incidental statistical learning.

How pom cheerleading improves the executive function of preschool children: the mediating role of speed and agility

Physical exercises can improve individuals’ physical health and cognition, but the internal influence path is unclear. This study aims to examine the influence of pom cheerleading training on physical fitness and executive function of preschool children and explore the relationship between sports training, physical fitness, and executive function. We selected seventy-one preschool children and divided them into the experimental group (n = 36) and the control group (n = 35). The experimental group kept a 12-week pom cheerleading training, and the exercises of the control group remained normal. Children’s physical fitness and executive function were tested, in one week before and after the experiment, respectively. Results of repeated measurements analysis of variance and structural equation model test showed: (1) after 12-week pom cheerleading training, in terms of physical fitness, the experimental group has a significant improvement over the control group on agility and speed; in terms of executive function, the inhibitory control and working memory of the experimental group were significantly enhanced over the control group. (2) Speed quality plays a partial mediating role between pom cheerleading training and inhibitory control; agility plays a major mediating role between pom cheerleading training and working memory. It is concluded that physical exercise can directly improve preschool children’s executive function, and indirectly enhance executive function mediated by physical fitness. Furthermore, structured and systematic physical education should be adopted for preschool children to cultivate their interest in sports and enhance their cognition.

Phasic activity of the locus-coeruleus is not a mediator of the relationship between fitness and inhibition in college-aged adults

Aerobic fitness is consistently and robustly associated with superior performance on assessments of cognitive control. One potential mechanism underlying this phenomenon is activation of the locus-coeruleus. Specifically, individuals with greater aerobic fitness may be better able to sustain engagement in a cognitively demanding task via a superior ability to meet the metabolic demands of this neural system. Accordingly, the present investigation examined 1) the relationship between aerobic fitness and phasic activation of the locus-coeruleus (indexed using pupillometry) and 2) the potential mediating influence of locus-coeruleus activity on the relationship between aerobic fitness and cognitive task performance. Participants performed an inhibition task while their pupillary responses were measured using an infrared eye tracker. A VO_2max test was then performed to determine individuals' aerobic fitness levels. Consistent with previous research, higher levels of aerobic fitness were related to shorter reaction time. However, phasic activity of the locus-coeruleus did not mediate this relationship - nor did it relate to aerobic fitness level. These results suggest that aerobic fitness does not relate to differences in locus-coeruleus activity in the context of cognitive control in college-aged adults.

Six-Minute Walking Test Performance Relates to Neurocognitive Abilities in Preschoolers

This study investigated the relationship between six-minute walking test (6MWT) distance walked and preschool-aged children’s academic abilities, and behavioral and event-related potentials (ERP) indices of cognitive control. There were 59 children (25 females; age: 5.0 ± 0.6 years) who completed a 6MWT (mean distance: 449.6 ± 82.0 m) to estimate cardiorespiratory fitness. The Woodcock Johnson Early Cognitive and Academic Development Test evaluated academic abilities. A modified Eriksen flanker, hearts and flowers task, and auditory oddball task eliciting ERPs (N2, P3) assessed cognitive control. After adjusting for adiposity, diet, and demographics, linear regressions resulted in positive relationships between 6MWT distance and General Intellectual Ability (β = 0.25, Adj R² = 0.04, p = 0.04) and Expressive Language (β = 0.30, Adj R² = 0.13, p = 0.02). 6MWT distance was positively correlated with congruent accuracy (β = 0.29, Adj R² = 0.18, p < 0.01) and negatively with incongruent reaction time (β = −0.26, Adj R² = 0.05, p = 0.04) during the flanker task, and positively with homogeneous (β = 0.23, Adj R² = 0.21, p = 0.04) and heterogeneous (β = 0.26, Adj R² = 0.40, p = 0.02) accuracy on the hearts and flowers task. Higher fit children showed faster N2 latencies and greater P3 amplitudes to target stimuli; however, these were at the trend level following the adjustment of covariates. These findings indicate that the positive influence of cardiorespiratory fitness on cognitive function is evident in 4–6-year-olds.

Physical Activity, Screen-Based Sedentary Behavior and Physical Fitness in Chinese Adolescents: A Cross-Sectional Study

Purpose: The aim of this study is to explore the relationship between screen-based sedentary behavior, physical activity and physical fitness among Chinese adolescents. Methods: This study randomly selected adolescents from 10 administrative districts in Shandong, China. The data gathering tools for demographic and other characteristics (gender, age, body mass index and socioeconomic status), PA (PAQ-A) and screen-based sedentary behavior (YRBSS) and physical fitness (NSPFH 2014) were utilized in this study. Statistical analysis was performed by T-test, chi-square test and multiple linear regression. Results: 10,002 adolescents (14.39 years ± 1.79) participated in the study. The results demonstrated that BMI and high TV viewing time had a significant negative correlation with physical fitness, but there was no association between the amount of time spent playing computer/video games and physical fitness among adolescents. High SES and physical activity in leisure time five or more times per week were significantly associated with most dimensions of physical fitness. Conclusions: the results suggest that we not only need to focus on adolescent risk behavior associated with low socioeconomic status and obesity, but also enforce physical activity and reduce sedentary television-watching behavior, which will be crucial pathways and strategies to improve the physical fitness of Chinese adolescents.

Effect of Vigorous Physical Activity on Executive Control in Middle-School Students

The purpose of this pilot study was to examine the acute effect of vigorous physical activity on executive control in eighth grade students from the U.S. Participants were eighth grade students (N = 68; 26 girls, 42 boys) recruited from one middle school located in the Mountain West region of the U.S. Two groups of participants were assigned to receive either a vigorous physical activity or a sedentary condition within a counter-balanced cross-over design using a 2-week washout. Both groups were administered Trails Making Tests A (TMT-A) and B (TMT-B) at 20- and 25-min post-treatment, respectively. Mixed design ANOVA tests with repeated measures examined differences between treatments on TMT-A and TMT-B performance and the modifying effect of sex. Students who completed the physical activity condition displayed a faster time to completion on the TMT-B compared to students who completed the sedentary condition (Mean difference = −6.5 s, p = 0.026, d = 0.42). There were no differences between treatment groups on TMT-A and no sex × treatment interactions (p > 0.05). This pilot study suggests that vigorous physical activity may improve executive control in middle-school students and adds to the existent literature that continues to examine the emerging link between physical activity and cognition in school-based settings.

Physical Fitness, Physical Activity, and the Executive Function in Children with Overweight and Obesity

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.

Executive and Reward-Related Function in Pediatric Obesity: A Meta-Analysis

OBJECTIVE

This study examined the effect of pediatric obesity on executive function and reward-related decision-making, cognitive processes that are relevant to obesogenic behaviors, and evaluated their association with sample (e.g., age, gender, intelligence, and socioeconomic status, SES) and study/task (e.g., categorical/continuous variable, food stimuli) characteristics.

METHODS

A random-effects meta-analysis was conducted using Hedge's g effect sizes of published studies from 1960 to 2016, limited to children younger than the age of 21 years without medical comorbidities. Analysis included estimation of heterogeneity (τ²), publication bias (funnel-plot symmetry and fail-safe N), and sensitivity analyses for sample and study/task characteristics.

RESULTS

Across 68 studies with 70 samples, obesity was associated with worse functioning overall (-0.24; 95CI: -0.30 to -0.19; p < 0.001) and for each component process (attention, switching, inhibition, interference, working memory, reward, delay of gratification: -0.19 to -0.38; p's < 0.017), except trait impulsivity (-0.06; 95CI: -0.18 to 0.07). Deficits increased with age and female composition of the sample for inhibition (p = 0.002). No other characteristics moderated effect of obesity.

CONCLUSIONS

Small-to-moderate negative associations with obesity were observed for executive and reward-related performance, but not on reported impulsivity in studies with children younger than the age of 21 years. These results were not moderated by IQ, SES, and study/task characteristics. Age and gender moderated association with inhibition, with a larger obesity-related deficit in older and predominantly female samples. These results suggest cognitive and demographic intervention targets for prevention and mitigation of obesogenic behavior.

Combined Effects of Physical Activity and Obesity on Cognitive Function: Independent, Overlapping, Moderator, and Mediator Models

This article reviews studies on physical activity, obesity, and cognition to explore how physical activity and obesity may work independently or together in affecting cognitive function. In particular, we propose six hypotheses derived from four conceptual models to advance our understanding of the combined effects of physical activity and obesity on cognition. The four conceptual models are distinguished by the presumed temporal relationship and the presumed correlation between physical activity and obesity and include an independent model, an overlapping model, a moderator model, and a mediator model. Among the 16 studies testing the effects of physical activity and obesity on cognition in a combined approach, the moderator model, viewing either physical activity or obesity as the potential moderator, was most frequently examined (n = 10), mediator (n = 3) and independent (n = 2) models received relatively less attention, and only a single study used an overlapping model. Results were mixed when considering the moderator, independent, and mediator models. The single study that took an overlapping model approach found support for the model hypothesis. One relevant observation from this review is that the variance within the small extant literature with respect to the choice of conceptual model limits our ability to make assertive conclusions relative to the relations among the examined variables. Given the logic supporting a combined effect of physical activity and obesity on cognition, researchers are encouraged to consider the possible models of the relationship as they design studies to further address this research question.

Physical Fitness, Grit, School Attendance, and Academic Performance among Adolescents

Objective

The purpose of this study was to examine the relationship of grit as a construct representing perseverance to overcoming barriers and the total number of school absences to academic performance (AP) while controlling for sociodemographics, fitness (i.e., PACER), and Body Mass Index (BMI).

Methods

Adolescents (N = 397, SD = 1.85; 80.9% females; 77.1% Hispanic) from an urban, minority-majority city in the Southern United States completed the FitnessGram® assessment of physical fitness (e.g., aerobic capacity and Body Mass Index (BMI)) and the valid and reliable short grit survey. The schools provided sociodemographics, attendance, and AP data for the adolescents.

Results

Adolescents with higher grit scores (r_s = 0.21, P < 0.001) and less total absences (r_s = −0.35, P < 0.001) performed better on AP. Hierarchical multiple regression indicated that grit and absences were associated with AP (β = 0.13, P < 0.01 and β = −0.35, P < 0.001, resp.).

Conclusions

Grit and a total number of absences are significant contributors to academic success, particularly among Hispanic adolescents. Further, grit and school attendance may serve as a better measure of protective factors over proximal health measures of cardiovascular health and BMI.

Fitness, Sleep-Disordered Breathing, Symptoms of Depression, and Cognition in Inactive Overweight Children: Mediation Models

OBJECTIVES

We used mediation models to examine the mechanisms underlying the relationships among physical fitness, sleep-disordered breathing (SDB), symptoms of depression, and cognitive functioning.

METHODS

We conducted a cross-sectional secondary analysis of the cohorts involved in the 2003-2006 project PLAY (a trial of the effects of aerobic exercise on health and cognition) and the 2008-2011 SMART study (a trial of the effects of exercise on cognition). A total of 397 inactive overweight children aged 7-11 received a fitness test, standardized cognitive test (Cognitive Assessment System, yielding Planning, Attention, Simultaneous, Successive, and Full Scale scores), and depression questionnaire. Parents completed a Pediatric Sleep Questionnaire. We used bootstrapped mediation analyses to test whether SDB mediated the relationship between fitness and depression and whether SDB and depression mediated the relationship between fitness and cognition.

RESULTS

Fitness was negatively associated with depression ( B = -0.041; 95% CI, -0.06 to -0.02) and SDB ( B = -0.005; 95% CI, -0.01 to -0.001). SDB was positively associated with depression ( B = 0.99; 95% CI, 0.32 to 1.67) after controlling for fitness. The relationship between fitness and depression was mediated by SDB (indirect effect = -0.005; 95% CI, -0.01 to -0.0004). The relationship between fitness and the attention component of cognition was independently mediated by SDB (indirect effect = 0.058; 95% CI, 0.004 to 0.13) and depression (indirect effect = -0.071; 95% CI, -0.01 to -0.17).

CONCLUSIONS

SDB mediates the relationship between fitness and depression, and SDB and depression separately mediate the relationship between fitness and the attention component of cognition.

Altered brain correlates of response inhibition and error processing in females with obesity and sweet food addiction: A functional magnetic imaging study

BACKGROUND

The aim of the present study was to evaluate the impulsivity and brain correlates of response inhibition and error processing among females with obesity and sweet food addiction (O & SFA).

METHODS

We evaluated the response inhibition and error processing by functional magnetic resonance imaging (fMRI) in subjects with O & SFA and controls. Twenty females with O & SFA and 20 controls were recruited. All subjects performed the event-related designed Go/No-go task under fMRI and completed questionnaires related to food craving and impulsivity.

RESULTS

The O & SFA group exhibited a higher score for impulsivity than did the control group. The O & SFA also exhibited lower brain activation when processing response inhibition over the right rolandic operculum and thalamus than controls. Both O & SFA and control groups exhibited activation of the insula and caudate during error processing. The activation over the left insula, precuneus, and bilateral putamen were higher in the subjects with O & SFA than for those in the control group.

CONCLUSION

Our results support the fact that the fronto-striatal network is involved in response inhibition, and the caudate and insula contributes to error processing. Furthermore, women with O & SFA have impaired rolandic operculum when processing response inhibition and have greater insular and putamen activation in maintain their error processing function.

Sedentary patterns, physical activity and health-related physical fitness in youth: a cross-sectional study

BACKGROUND

Strong evidence indicates that moderate-vigorous physical activity (MVPA) is positively associated with fitness in youth, independent of total sedentary-time. Sedentary-time appears negatively associated with fitness only when it replaces MVPA. However, whether different sedentary-patterns affect health-related fitness is unknown.

METHODS

The associations between MVPA and sedentary-patterns with physical fitness were examined in 2698 youths (1262 boys) aged 13.4 ± 2.28 years. Sedentary-time (counts · minute-1 < 100) and PA were objectively measured by accelerometry. Each break (≥100 counts · min-1 < 2295) in sedentary-time and the frequency of daily bouts in non-prolonged (<30 min) and prolonged (≥30 min) sedentary-time were determined. The FITNESSGRAM® test battery was used to assess fitness. A standardized fitness composite-score (z-score) was calculated by summing the individual z-scores of the five tests adjusted to age and sex.

RESULTS

Positive associations between MVPA and fitness were observed in both boys (β = 0.013, 95% CI: 0.005; 0.021) and girls (β = 0.014, 95% CI: 0.006; 0.022), independent of sedentary-patterns. Modest associations were found for the breaks in sedentary-time with fitness (β = 0.026, 95% CI: 0.009; 0.042), independent of total sedentary-time and MVPA in boys. In girls, non-prolonged sedentary bouts were positively associated with fitness (β = 0.014, 95% CI: 0.003; 0.024), independent of total sedentary-time and MVPA.

CONCLUSIONS

These results reinforce that, independent of the time and patterns of sedentary behavior, MVPA is consistently associated with fitness in youth. Modest and inconsistent associations were found for sedentary behaviors. Breaking-up sedentary-time in boys and non-prolonged sedentary bouts in girls were positively associated with fitness, independent of total sedentary-time and MVPA. In order to enhance youth's fitness, public health recommendations should primarily target MVPA, still, suggestion to reduce and break-up sedentary-time may also be considered.

A Critical Proton MR Spectroscopy Marker of Alzheimer's Disease Early Neurodegenerative Change: Low Hippocampal NAA/Cr Ratio Impacts APOE ɛ4 Mexico City Children and Their Parents

Severe air pollution exposures produce systemic, respiratory, myocardial, and brain inflammation and Alzheimer's disease (AD) hallmarks in clinically healthy children. We tested whether hippocampal metabolite ratios are associated with contrasting levels of air pollution, APOE, and body mass index (BMI) in paired healthy children and one parent sharing the same APOE alleles. We used 1H-MRS to interrogate bilateral hippocampal single-voxel in 57 children (12.45 ± 3.4 years) and their 48 parents (37.5 ± 6.78 years) from a low pollution city versus Mexico City (MC). NAA/Cr, Cho/Cr, and mI/Cr metabolite ratios were analyzed. The right hippocampus NAA/Cr ratio was significantly different between cohorts (p = 0.007). The NAA/Cr ratio in right hippocampus in controls versus APOE ɛ4 MC children and in left hippocampus in MC APOE ɛ4 parents versus their children was significantly different after adjusting for age, gender, and BMI (p = 0.027 and 0.01, respectively). The NAA/Cr ratio is considered reflective of neuronal density/functional integrity/loss of synapses/higher pTau burden, thus a significant decrease in hippocampal NAA/Cr ratios may constitute a spectral marker of early neurodegeneration in young urbanites. Decreases in NAA/Cr correlate well with cognitive function, behavioral symptoms, and dementia severity; thus, since the progression of AD starts decades before clinical diagnosis, our findings support the hypothesis that under chronic exposures to fine particulate matter and ozone above the standards, neurodegenerative processes start in childhood and APOE ɛ4 carriers are at higher risk. Gene and environmental factors are critical in the development of AD and the identification and neuroprotection of young urbanites at high risk must become a public health priority.

Physical Activity Interventions for Neurocognitive and Academic Performance in Overweight and Obese Youth: A Systematic Review

This article examines cognitive, academic, and brain outcomes of physical activity in overweight or obese youth, with attention to minority youth who experience health disparities. Physically active academic lessons may have greater immediate cognitive and academic benefits among overweight and obese children than normal-weight children. Quasi-experimental studies testing physical activity programs in overweight and obese youth show promise; a few randomized controlled trials including African Americans show efficacy. Thus, making academic lessons physically active may improve inhibition and attentiveness, particularly in overweight youngsters. Regular physical activity may be efficacious for improving neurologic, cognitive, and achievement outcomes in overweight or obese youth.

Independent Associations of Organized Physical Activity and Weight Status with Children's Cognitive Functioning: A Matched-Pairs Design

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 matched-pairs 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.

Age Moderates the Association of Aerobic Exercise with Initial Learning of an Online Task Requiring Cognitive Control

The aim of this study was to examine whether people differed in change in performance across the first five blocks of an online flanker task and whether those trajectories of change were associated with self-reported aerobic or resistance exercise frequency according to age. A total of 8752 men and women aged 13-89 completed a lifestyle survey and five 45-s games (each game was a block of ~46 trials) of an online flanker task. Accuracy of the congruent and incongruent flanker stimuli was analyzed using latent class and growth curve modeling adjusting for time between blocks, whether the blocks occurred on the same or different days, education, smoking, sleep, caffeinated coffee and tea use, and Lumosity training status ("free play" or part of a "daily brain workout"). Aerobic and resistance exercise were unrelated to first block accuracies. For the more cognitively demanding incongruent flanker stimuli, aerobic activity was positively related to the linear increase in accuracy [B=0.577%, 95% confidence interval (CI), 0.112 to 1.25 per day above the weekly mean of 2.8 days] and inversely related to the quadratic deceleration of accuracy gains (B=-0.619% CI, -1.117 to -0.121 per day). An interaction of aerobic activity with age indicated that active participants younger than age 45 had a larger linear increase and a smaller quadratic deceleration compared to other participants. Age moderates the association between self-reported aerobic, but not self-reported resistance, exercise and changes in cognitive control that occur with practice during incongruent presentations across five blocks of a 45-s online, flanker task.

The Relationship between Total Water Intake and Cognitive Control among Prepubertal Children

BACKGROUND

Cognitive control (also known as executive function) encompasses mental processes that underlie goal-directed behavior, and it enables us to adjust our behavior according to changing environmental demands. Previous research among children has demonstrated that aerobic fitness and obesity have contrasting and selective effects on cognitive control. However, the relationship between water intake and childhood cognitive control remains inadequately studied. This study investigated the relationship between total water intake and cognitive control among prepubertal children (8-9-year olds).

METHODS

Children between 8 and 9 years of age (n = 63) performed a modified flanker task to assess cognitive control related to inhibition (ability to resist distractions and maintain focus). Diet was measured using 3-day food records. Total water was defined as water consumed from drinking water, beverages, and food.

RESULTS

A comparison of task performance across the median intake of total water revealed that children above the median exhibited shorter reaction times across multiple conditions of the flanker task, requiring variable amounts of cognitive control. Further, after adjustment of age, IQ, socioeconomic status, weight status, and aerobic fitness level, the proportion of intake comprised of water (%TW) was negatively correlated with reaction time interference, that is, the ability to maintain task performance when task conditions demanded greater inhibition.

CONCLUSIONS

These results indicate an association between water intake and cognitive control using a task that modulates inhibition. Specifically, higher water intake correlated with greater ability to maintain task performance when inhibitory demands are increased. Future work is needed to determine the mechanism by which water influences cognitive control among children.

The relation of saturated fats and dietary cholesterol to childhood cognitive flexibility

Identification of health behaviors and markers of physiological health associated with childhood cognitive function has important implications for public health policy targeted toward cognitive health throughout the life span. Although previous studies have shown that aerobic fitness and obesity exert contrasting effects on cognitive flexibility among prepubertal children, the extent to which diet plays a role in cognitive flexibility has received little attention. Accordingly, this study examined associations between saturated fats and cholesterol intake and cognitive flexibility, assessed using a task switching paradigm, among prepubertal children between 7 and 10 years (N = 150). Following adjustment of confounding variables (age, sex, socioeconomic status, IQ, VO2max, and BMI), children consuming diets higher in saturated fats exhibited longer reaction time during the task condition requiring greater amounts of cognitive flexibility. Further, increasing saturated fat intake and dietary cholesterol were correlated with greater switch costs, reflecting impaired ability to maintain multiple task sets in working memory and poorer efficiency of cognitive control processes involved in task switching. These data are among the first to indicate that children consuming diets higher in saturated fats and cholesterol exhibit compromised ability to flexibly modulate their cognitive operations, particularly when faced with greater cognitive challenge. Future longitudinal and intervention studies are necessary to comprehensively characterize the interrelationships between diet, aerobic fitness, obesity, and children's cognitive abilities.