Aerobic fitness is associated with greater hippocampal cerebral blood flow in children

Cerebral blood flow and structural connectivity after working memory or physical training in paediatric cancer survivors - Exploratory findings

Paediatric cancer survivors often suffer from cognitive long-term difficulties. Consequently, strengthening cognition is of major clinical relevance. This study investigated cerebral changes in relation to cognition in non-brain tumour paediatric cancer survivors after working memory or physical training compared to a control group. Thirty-four children (≥one-year post-treatment) either underwent eight weeks of working memory training (n = 10), physical training (n = 11), or a waiting period (n = 13). Cognition and MRI, including arterial spin labelling and diffusion tensor imaging, were assessed at three time points (baseline, post-training, and three-month follow-up). Results show lower cerebral blood flow immediately after working memory training (z = -2.073, p = .038) and higher structural connectivity at the three-month follow-up (z = -2.240, p = .025). No cerebral changes occurred after physical training. Short-term changes in cerebral blood flow correlated with short-term changes in cognitive flexibility (r = -.667, p = .049), while long-term changes in structural connectivity correlated with long-term changes in working memory (r = .786, p = .021). Despite the caution given when interpreting data from small samples, this study suggests a link between working memory training and neurophysiological changes. Further research is needed to validate these findings.

Relations between 24-h movement behaviors, declarative memory, and hippocampal volume in early childhood

This study aimed to determine if 24-h movement behaviors (sedentary time, physical activity, and sleep), considered independently and together, were associated with declarative memory and hippocampal volume in late early childhood. Observational data were obtained from preschool-aged children (timepoint 1: n = 35 children, 3.9 ± 0.5 years; 6 months later: n = 28 children, 4.5 ± 0.5 years). Movement behaviors were measured with actigraphy. Outcomes were declarative memory and hippocampal subregion volumes. Multilevel models explored movement behaviors independently as absolute values, and with both absolute total activity, 24-h sleep duration, and night sleep efficiency. Movement behaviors were also explored as compositions in linear regression models. In independent models, sleep duration and moderate to vigorous physical activity were positively associated with total and right hippocampal volumes, respectively. When examined together, children meeting sleep recommendations were more likely to have larger total, right and left hemisphere, body, and tail hippocampal volumes. In our sample of preschool children, we observed positive associations between sleep duration and hippocampal volume, independent of age. To improve our understanding of the connections between 24-h behaviors and brain health in early childhood, larger samples that also consider the context and subcomponents of movement behaviors may be warranted.

Mechanisms Linking Physical Activity With Mental Health in Children and Adolescents With Neurodevelopmental Disorders: A Systematic Review

INTRODUCTION

Physical activity (PA) is a promising way to improve mental health in children and adolescents with neurodevelopmental disorders (NDDs). However, the underlying mechanisms remain unclear. The current review aimed to explore the potential neurobiological, psychosocial, and behavioral mechanisms between PA interventions and mental health in children and adolescents with NDDs.

METHODS

Web of Science, PsycINFO, SPORTDiscus, MEDLINE, CINAHL, and ERIC were searched from inception to June 2023. Randomized controlled trials/quasi-experimental designs applying PA interventions and reporting at least one mental health outcome and at least one potential mechanism in children and adolescents with NDDs were included. The best evidence synthesis rating system was adopted to determine the strength and consistency of potential mechanisms and was performed in 2024.

RESULTS

In total, 45 studies were included, 29 of which were randomized controlled trials and 16 were quasi-experimental, with a total of 1,751 participants. According to the best evidence synthesis rating system, neurobiological (theta activity and P3 amplitude), psychosocial (social skills and social participation), and behavioral (motor skills and sleep) mechanisms were the frequently examined and consistent mechanisms through which PA affected mental health in children and adolescents with NDDs. However, evidence regarding P3 latency, beta activity, and physical self-concept was insufficient.

DISCUSSION

Future PA interventions could consider neurobiological (theta activity and P3 amplitude), psychosocial (social skills and social participation), and behavioral (motor skills and sleep) mechanisms. Alternatively, PA can be developed as an adjunctive approach with interventions that specifically focus on these mechanisms to enhance mental health in children and adolescents with NDDs.

A 10-Year Review on Advancements in Identifying and Treating Intellectual Disability Caused by Genetic Variations

Intellectual disability (ID) is a prevalent neurodevelopmental disorder characterized by neurodevelopmental defects such as the congenital impairment of intellectual function and restricted adaptive behavior. However, genetic studies have been significantly hindered by the extreme clinical and genetic heterogeneity of the subjects under investigation. With the development of gene sequencing technologies, more genetic variations have been discovered, assisting efforts in ID identification and treatment. In this review, the physiological basis of gene variations in ID is systematically explained, the diagnosis and therapy of ID is comprehensively described, and the potential of genetic therapies and exercise therapy in the rehabilitation of individuals with intellectual disabilities are highlighted, offering new perspectives for treatment approaches.

Long-term voluntary running improves cognitive ability in developing mice by modulating the cholinergic system, antioxidant ability, and BDNF/PI3K/Akt/CREB pathway

Moderate physical exercise has positive effects on memory. The present study aimed to investigate the impact of long-term exercise on spatial memory in developing mice, as well as its association with the cholinergic system, antioxidant activities, apoptosis factor, and BDNF/PI3K/Akt/CREB pathway in the brain. In this study, Y maze and Novel object recognition (NOR) tests were employed to assess the impact of long-term voluntary exercise on memory. The cholinergic system, antioxidant activities, and apoptosis factors in the brain were quantified using Elisa. Additionally, western blot analysis was conducted to determine the expression of relevant proteins in the BDNF/PI3K/Akt/CREB pathway. The findings demonstrated that prolonged voluntary wheel running exercise enhanced memory in developing mice, concomitant with increased catalase (CAT) activity and decreased malondialdehyde (MDA) levels in the brain. Moreover, it could also increase the hippocampal acetylcholine (ACh) content and suppress the expression of neuronal apoptosis protein. Additionally, exercise also upregulated the expression of brain-derived neurotrophic factor (BDNF), tropomyosin receptor kinase B (TrkB), phosphoinositide 3 kinases (PI3K), Akt, cAMP response element-binding protein (CREB), and phosphorylated cAMP response element-binding protein (p-CREB) in the hippocampus. These findings suggest that long-term voluntary wheel running exercise improves the spatial memory of developing mice by modulating the cholinergic system, antioxidant activities, apoptosis factors, and activating the BDNF/PI3K/Akt/CREB pathway.

Volleyball training improves working memory in children aged 7 to 12 years old: an fNIRS study

This study aimed to investigate the effect of a 12-wk extracurricular volleyball training on working memory from both behavioral and cerebral aspects. A total of 80 children were randomized assigned to (i) the experimental group, who engaged in extracurricular volleyball training for 60 min, thrice a week for 12 wk, and (ii) the control group, who maintained their regular daily routine. Working memory was evaluated in both groups using the N-back task before and after the intervention. Furthermore, functional near-infrared spectroscopy was employed to monitor the level of oxygenated hemoglobin in the prefrontal cortex. The experimental group performed better in the behavioral task than the control group, as evidenced by a shorter response time and a higher correct rate. The functional near-infrared spectroscopy results suggested that the activation of the left dorsolateral prefrontal cortex was significantly higher in the experimental group than in the control group. In addition, correlation analyses showed that the enhancement of left dorsolateral prefrontal cortex activation was significantly correlated with decreasing response time and improving response accuracy in the N-back task. These findings suggest that the left dorsolateral prefrontal cortex is likely the neural substrate for improved working memory performance elicited by 12-wk open skill exercise.

Effects of lifestyle factors on leukocytes in cardiovascular health and disease

Exercise, stress, sleep and diet are four distinct but intertwined lifestyle factors that influence the cardiovascular system. Abundant epidemiological, clinical and preclinical studies have underscored the importance of managing stress, having good sleep hygiene and responsible eating habits and exercising regularly. We are born with a genetic blueprint that can protect us against or predispose us to a particular disease. However, lifestyle factors build upon and profoundly influence those predispositions. Studies in the past 10 years have shown that the immune system in general and leukocytes in particular are particularly susceptible to environmental perturbations. Lifestyle factors such as stress, sleep, diet and exercise affect leukocyte behaviour and function and thus the immune system at large. In this Review, we explore the various mechanisms by which lifestyle factors modulate haematopoiesis and leukocyte migration and function in the context of cardiovascular health. We pay particular attention to the role of the nervous system as the key executor that connects environmental influences to leukocyte behaviour.

Measuring Quantitative Cerebral Blood Flow in Healthy Children: A Systematic Review of Neuroimaging Techniques

Cerebral blood flow (CBF) is an important hemodynamic parameter to evaluate brain health. It can be obtained quantitatively using medical imaging modalities such as magnetic resonance imaging and positron emission tomography (PET). Although CBF in adults has been widely studied and linked with cerebrovascular and neurodegenerative diseases, CBF data in healthy children are sparse due to the challenges in pediatric neuroimaging. An understanding of the factors affecting pediatric CBF and its normal range is crucial to determine the optimal CBF measuring techniques in pediatric neuroradiology. This review focuses on pediatric CBF studies using neuroimaging techniques in 32 articles including 2668 normal subjects ranging from birth to 18 years old. A systematic literature search was conducted in PubMed, Embase, and Scopus and reported following the preferred reporting items for systematic reviews and meta-analyses (PRISMA). We identified factors (such as age, gender, mood, sedation, and fitness) that have significant effects on pediatric CBF quantification. We also investigated factors influencing the CBF measurements in infants. Based on this review, we recommend best practices to improve CBF measurements in pediatric neuroimaging. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.

Effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness: A multi-country cluster randomized controlled trial

PURPOSE

To examine the effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness in children aged 7-8 years.

METHODS

Twenty schools in 5 different European countries (2 second-grade classrooms per school) participated in a cluster randomized controlled trial (Sport at School trial). Participants were assigned to either a control group, which continued with their habitual physical education lessons, or to an intervention group, which replaced these lessons with a 1-year karate intervention (Karate Mind and Movement program). A total of 721 children (344 girls and 377 boys, 7.4 ± 0.5 years old, mean ± SD) completed the study, of which 333 and 388 were assigned to the control group and intervention group, respectively. Outcomes included academic performance (average grade), psychosocial functioning (Strengths and Difficulties Questionnaire for parents), and different markers of physical fitness (cardiorespiratory fitness, balance, and flexibility).

RESULTS

The intervention provided small but significant benefits compared to the control group for academic achievement (d = 0.16; p = 0.003), conduct problems (d = -0.28; p = 0.003), cardiorespiratory fitness (d = 0.36; p < 0.001), and balance (d = 0.24; p = 0.015). There was a trend towards significant benefits for flexibility (d = 0.24; p = 0.056). No significant benefits were observed for other variables, including psychosocial difficulties, emotional symptoms, hyperactivity/inattention, peer problems, or prosocial behaviour (all p > 0.05).

CONCLUSION

A 1-year school-based karate intervention was effective in improving academic achievement, conduct problems, and physical fitness in primary school children. The results support the inclusion of karate during physical education lessons.

Cerebral blood flow and cerebrovascular reactivity are modified by maturational stage and exercise training status during youth

NEW FINDINGS

What is the central question of this study? Gonadal hormones modulate cerebrovascular function while insulin-like growth factor 1 (IGF-1) facilitates exercise-mediated cerebral angiogenesis; puberty is a critical period of neurodevelopment alongside elevated gonadal hormone and IGF-1 activity: but whether exercise training across puberty enhances cerebrovascular function is unkown. What is the main finding and its importance? Cerebral blood flow is elevated in endurance trained adolescent males when compared to untrained counterparts. However, cerebrovascular reactivity to hypercapnia is faster in trained vs. untrained children, but not adolescents. Exercise-induced improvements in cerebrovascular function are attainable as early as the first decade of life.

ABSTRACT

Global cerebral blood flow (gCBF) and cerebrovascular reactivity to hypercapnia (CV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ ) are modulated by gonadal hormone activity, while insulin-like growth factor 1 facilitates exercise-mediated cerebral angiogenesis in adults. Whether critical periods of heightened hormonal and neural development during puberty represent an opportunity to further enhance gCBF andCV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ is currently unknown. Therefore, we used duplex ultrasound to assess gCBF andCV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ in n = 128 adolescents characterised as endurance-exercise trained (males: n = 30, females: n = 36) or untrained (males: n = 29, females: n = 33). Participants were further categorised as pre- (males: n = 35, females: n = 33) or post- (males: n = 24, females: n = 36) peak height velocity (PHV) to determine pubertal or 'maturity' status. Three-factor ANOVA was used to identify main and interaction effects of maturity status, biological sex and training status on gCBF andCV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ . Data are reported as group means (SD). Pre-PHV youth demonstrated elevated gCBF and slowerCV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ mean response times than post-PHV counterparts (both: P ≤ 0.001). gCBF was only elevated in post-PHV trained males when compared to untrained counterparts (634 (43) vs. 578 (46) ml min-1 ; P = 0.007). However,CV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ mean response time was faster in pre- (72 (20) vs. 95 (29) s; P ≤ 0.001), but not post-PHV (P = 0.721) trained youth when compared to untrained counterparts. Cardiorespiratory fitness was associated with gCBF in post-PHV youth (r2  = 0.19; P ≤ 0.001) andCV R C O 2 ${\mathrm{CV}}{{\mathrm{R}}_{{\mathrm{C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ mean response time in pre-PHV youth (r2  = 0.13; P = 0.014). Higher cardiorespiratory fitness during adolescence can elevate gCBF while exercise training during childhood primes the development of cerebrovascular function, highlighting the importance of exercise training during the early stages of life in shaping the cerebrovascular phenotype.

Exercise Reshapes the Brain: Molecular, Cellular, and Structural Changes Associated with Cognitive Improvements

Physical exercise is well known as a non-pharmacological and holistic therapy believed to prevent and mitigate numerous neurological conditions and alleviate ageing-related cognitive decline. To do so, exercise affects the central nervous system (CNS) at different levels. It changes brain physiology and structure, promoting cognitive improvements, which ultimately improves quality of life. Most of these effects are mediated by neurotrophins release, enhanced adult hippocampal neurogenesis, attenuation of neuroinflammation, modulation of cerebral blood flow, and structural reorganisation, besides to promote social interaction with beneficial cognitive outcomes. In this review, we discuss, based on experimental and human research, how exercise impacts the brain structure and function and how these changes contribute to cognitive improvements. Understanding the mechanisms by which exercise affects the brain is essential to understand the brain plasticity following exercise, guiding therapeutic approaches to improve the quality of life, especially in obesity, ageing, neurodegenerative disorders, and following traumatic brain injury.

Hippocampal Resting State Functional Connectivity Associated with Physical Activity in Periadolescent Children

Periadolescence is a neurodevelopmental period characterized by structural and functional brain changes that are associated with cognitive maturation. The development of the functional connectivity of the hippocampus contributes to cognitive maturation, especially memory processes. Notably, hippocampal development is influenced by lifestyle factors, including physical activity. Physical activity has been associated with individual variability in hippocampal functional connectivity. However, this relationship has not been characterized in a developmental cohort. In this study, we aimed to fill this gap by investigating the relationship between physical activity and the functional connectivity of the hippocampus in a cohort of periadolescents aged 8-13 years (N = 117). The participants completed a physical activity questionnaire, reporting the number of days per week they performed 60 min of physical activity; then, they completed a resting-state functional MRI scan. We observed that greater physical activity was significantly associated with differences in hippocampal functional connectivity in frontal and temporal regions. Greater physical activity was associated with decreased connectivity between the hippocampus and the right superior frontal gyrus and increased connectivity between the hippocampus and the left superior temporal sulcus. Capturing changes in hippocampal functional connectivity during key developmental periods may elucidate how lifestyle factors including physical activity influence brain network connectivity trajectories, cognitive development, and future disease risk.

Examining the relationship between aerobic fitness and cognitive control processes: An SFT and ERP study

Previous studies have demonstrated a positive relationship between aerobic fitness and cognitive control, the ability to inhibit distractions (conflict control) or impulsive actions (response inhibition). However, it is unknown whether these sub-processes and their underlying information processing capacity are differentially related to aerobic fitness. To address this question, we employed a go/no-go version of the redundant-target task, which was administered concurrently with the recording of event-related potentials (ERPs) and the use of a reaction-time based diagnostic tool known as system factorial technology (SFT). Our sample consisted of 46 young male adults with varying levels of aerobic fitness: the high-fit group (n = 23; aged 21.33 ± 2.44 years; VO2max 58.83 ± 6.93 ml/kg/min) and the low-fit group (n = 23; aged 22.30 ± 1.40 years; VO2max 41.90 ± 4.01 ml/kg/min). The results showed that the high-fit group exhibited a lower false-alarm rate compared to the low-fit group. However, there was no difference in processing speed between the two groups. The SFT analysis revealed that the high-fit group had more efficient information processing for earlier responses, but not later responses, compared to the low-fit group. Analysis of the ERPs indicated that the high-fit group had larger N2d amplitudes and shorter P3d latencies during conflict control compared to the low-fit group, while there were no such effects for the process of response inhibition. These findings suggest that aerobic fitness may be differentially related to the temporal dynamics and sub-processes of cognitive control.

Valuing embodiment: insights from dance practice among people living with dementia

There is a growing appreciation for the ability of person-centered arts-based approaches to extend multiple domains of brain health of people living with dementia. Dance is a multi-modal artistic engagement which has positive impacts on cognition, mobility and the emotional and social aspects of brain health. Although research into multiple domains of brain health among older adults and people living with dementia is promising, several gaps remain, specifically in understanding the benefits of co-creative and improvisational dance practices. Collaborative research between dancers, researchers, people living with dementia and care partners is needed to design and evaluate future research on dance and to determine relevance and usability. Furthermore, the respective praxes and experience of researchers, dance artists and people living with dementia contribute distinctly and uniquely to the identification and the assignment of value to dance in the context of the lives of people living with dementia. In this manuscript the author, a community-based dance artist, creative aging advocate and Atlantic Fellow for Equity in Brain Health, discusses current challenges and gaps in the understanding of the value of dance for and with people living with dementia and how transdisciplinary collaboration between neuroscientists, dance artists and people living with dementia can advance collective comprehension and implementation of dance practice.

The unique contribution of motor ability to visuospatial working memory in school-age children: Evidence from event-related potentials

This study investigated the unique contribution of motor ability to visuospatial working memory (VSWM) and neuroelectric activity in school-age children. Seventy-six children aged 8.7 ± 1.1 years participated in this cross-sectional study. We assessed aerobic fitness using the 20-m endurance shuttle run test, muscular fitness (endurance, power) using a standard test battery, and motor ability (manual dexterity, ball skills, and static and dynamic balance) using the Movement Assessment Battery for Children. A modified delayed match-to-sample test was used to assess VSWM and the P3 component of event-related potentials. Hierarchical regression analyses indicated that greater aerobic fitness was associated with smaller coefficient of variation of reaction time (p = .008), greater muscular fitness was associated with higher response accuracy (p = .022), greater motor ability was associated with higher response accuracy (p < .001) and increased P3 mean amplitude (p < .001) after controlling for age. Furthermore, the positive associations of motor ability with response accuracy (p = .001) were independent of muscular fitness. The findings from this study provide new insight into the differential associations between health-related fitness domains and VSWM, highlighting the influence of motor ability on brain health and cognitive development during childhood.

School-based physical activity interventions and language skills: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

School-based physical activity (PA) interventions have proven beneficial for improving cognitive performance and overall academic achievement, but their benefits on language skills remain unclear. We aimed to assess the effects of school-based PA interventions on language skills in children and adolescents.

DESIGN

Systematic review with meta-analysis.

METHODS

A systematic search was performed in PubMed, PsycINFO and Scopus until September 10th, 2022. We included randomized controlled trials (RCTs) that performed a school-based PA intervention in children/adolescents and that assessed language-related outcomes (i.e., reading, spelling, vocabulary, verbal fluency, comprehension and grammar) or language school grades. Random effect meta-analyses were conducted to pool study results.

RESULTS

Thirty-one studies (18,651 participants) were finally included. Significant benefits were observed for reading (standardized mean difference [SMD]: 0.15; 95% confidence interval [CI]: 0.08, 0.22), vocabulary (SMD: 0.71; 95%CI: 0.44, 0.97), and comprehension (SMD: 0.24; 95%CI: 0.09, 0.40), with a non-significant trend (p = 0.083) also observed for language school grades (SMD: 0.40; 95%CI: -0.05, 0.86). No significant benefits were observed for spelling or verbal fluency (both p > 0.05), and no meta-analysis could be performed for grammar skills. No consistent differences were observed between integrated (i.e., performing PA along with the academic content) and non-integrated PA interventions (e.g., extra physical education lessons).

CONCLUSIONS

School-based PA interventions appear as an effective strategy for improving different language-related skills, although further research is needed to determine how interventions' and participants' characteristics moderate these effects.

Does heart rate variability mediate the association between chronic stress, cardiorespiratory fitness, and working memory in young adults?

Young adulthood is a demanding development phase rendering individuals at risk for high levels of stress. While chronic stress may impair working memory maintenance, cardiorespiratory fitness is suggested to have a protective effect. Heart rate variability (HRV) contributes to this cognitive domain, but also retaliates to stress and aerobic exercise. Therefore, the present study investigated the mediating role of resting HRV on the association between chronic stress, cardiorespiratory fitness, and working memory maintenance in young healthy adults. Healthy participants (N = 115, 48% female) aged 18-35 years (M = 24.1, SD = 3.8) completed the Åstrand test on a bicycle ergometer to estimate maximal oxygen consumption [ V ̇ O 2 max $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\max } $$ (ml/min/kg)]. In addition, working memory maintenance was assessed using the modified Sternberg task with low (three items) and high cognitive load (six items). Using electrocardiography, HRV was recorded and the LF/HF ratio was extracted for mediation analyses. Path analysis revealed that cardiorespiratory fitness was significantly associated with accuracy on high cognitive load trials (β = 0.19, p = 0.035), but not on trials with low cognitive load. Perceived levels of chronic stress failed to show a significant association with working memory maintenance, independently of cognitive load. The pattern of results remained unchanged after introduction of HRV as a mediator (β = 0.18, p = 0.045). In conclusion, higher cardiorespiratory fitness is associated with better maintenance of verbal information in working memory. However, this association cannot be explained by vagal influences on memory processing driven by the autonomic nervous system.

Sport Participation and Academic Performance in Young Elite Athletes

Strong evidence supports physical activity and fitness levels being positively associated with cognitive performance and overall academic performance in youth. This also applies to sports participation. However, whether participation in sports at the elite level is associated with greater academic performance remains unknown. Thus, the present study aimed to compare the academic performance of young elite athletes to that of control students, as well as to analyze whether the type of sport mediates these results. Between 2010 and 2019, all students from the last Baccalaureate course of the Spanish Elite Sport High School-which also includes non-elite athletes and recreational athlete students, who were categorized as controls-participated in this study. Academic performance was assessed through both the grade point average of the two last Baccalaureate courses and through the average grades from the University Entrance Examinations. Athletes were categorized attending to different sport classifications. A total of 1126 adolescents (570 girls, 18.2 ± 0.6 years) participated in the study, of which 483 and 643 were categorized as elite athletes and control students, respectively. Elite athletes attained a lower overall academic performance than controls (p < 0.001), which was confirmed for both sexes (p < 0.001). These differences were separately confirmed for most academic subjects (p < 0.05), as well as when attending to different sport classifications (all p > 0.05). Young elite athletes attained a lower academic performance than their non-elite peers, regardless of their type of sport. These findings highlight the importance of programs aimed at facilitating dual careers among young elite athletes.

Effect of high-intensity interval training on hippocampal metabolism in older adolescents

Although well-evidenced in older adults, the effects of exercise on the hippocampus in youth are relatively unknown. This study examined the impact of a 6-month school-based physical activity intervention on hippocampal metabolism in adolescents using magnetic resonance spectroscopy. A subset of lower fit older adolescents [N = 56, 61% female, 16.1 ± 0.4 years] was included from four secondary schools (10 classes) in New South Wales, Australia, who were participating in a larger cluster randomized controlled trial. Participants were randomized to the Burn 2 Learn (B2L) intervention (five classes, 30 participants) or a control group (five classes, 26 participants). Changes in hippocampal metabolism were assessed using linear mixed models adjusted for clustering at the class level. We observed group-by-time effects for the B2L intervention on N-acetylaspartate (NAA) (+2.66 mmol/L, 95% CI 0.20 to 5.11, d = 0.66) and glutamate+glutamine (Glx) (+3.38 mmol/L, 95% CI 0.34 to 6.42, d = 0.67) in the left hippocampus. Increases in left hippocampal NAA and Glx concentrations were associated with improvements in cardiorespiratory fitness (NAA: r_s  = 0.52, p = .016; Glx: r_s  = 0.57, p = .007), lower body muscular fitness (NAA: r_s  = 0.49, p = .018; Glx: r_s  = 0.59, p = .003), and working memory (NAA: r_s  = 0.42, p = .032; Glx: r_s  = 0.43, p = .028) in the intervention group. Our findings suggest physical activity may improve hippocampal metabolism in lower fit older adolescents with implications for working memory. Further studies involving larger samples are needed to replicate our findings.

Relations between physical activity and hippocampal functional connectivity: Modulating role of mind wandering

Physical activity is critical for maintaining cognitive and brain health. Previous studies have indicated that the effect of physical activity on cognitive and brain function varies between individuals. The present study aimed to examine whether mind wandering modulated the relations between physical activity and resting-state hippocampal functional connectivity. A total of 99 healthy adults participated in neuroimaging data collection as well as reported their physical activity in the past week and their propensity to mind wandering during typical activities. The results indicated that mind wandering was negatively related to the resting-state functional connectivity between hippocampus and right inferior occipital gyrus. Additionally, for participants with higher level of mind wandering, physical activity was negatively related to hippocampal connectivity at left precuneus and right precentral gyrus. In contrast, such relations were positive at right medial frontal gyrus and bilateral precentral gyrus for participants with lower level of mind wandering. Altogether, these findings indicated that the relations between physical activity and hippocampal functional connectivity vary as a function of mind wandering level, suggesting that individual differences are important to consider when we aim to maintain or improve cognitive and brain health through increasing physical activity.

Regional cortical perfusion increases induced by a 6-month endurance training in young sedentary adults

Physical inactivity is documented as a health risk factor for chronic diseases, accelerated aging, and cognitive impairment. Physical exercise, on the other hand, plays an important role in healthy aging by promoting positive muscular, cardiovascular, and central nervous system adaptions. Prior studies on the effects of exercise training on cerebral perfusion have focused largely on elderly cohorts or patient cohorts, while perfusion effects of exercise training in young sedentary adults have not yet been fully assessed. Therefore, the present study examined the physiological consequence of a 6-month endurance exercise training on brain perfusion in 28 young sedentary adults randomly assigned to an intervention group (IG; regular physical exercise) or a control group (CG; without physical exercise). The IG performed an extensive running interval training three times per week over 6 months. Performance diagnostics and MRI were performed every 2 months, and training intensity was adapted individually. Brain perfusion measurements with pseudo-continuous arterial spin labeling were analyzed using the standard Oxford ASL pipeline. A significant interaction effect between group and time was found for right superior temporal gyrus (STG) perfusion, driven by an increase in the IG and a decrease in the CG. Furthermore, a significant time effect was observed in the right middle occipital region in the IG only. Perfusion increases in the right STG, in the ventral striatum, and in primary motor areas were significantly associated with increases in maximum oxygen uptake (VO_2max). Overall, this study identified region-specific increases in local perfusion in a cohort of young adults that partly correlated with individual performance increases, hence, suggesting exercise dose dependency. Respective adaptations in brain perfusion are discussed in the context of physical exercise-induced vascular plasticity.

A Sustainable Swedish School Intervention with Extra Aerobic Exercise—Its Organization and Effects on Physical Fitness and Academic Achievement

A large majority of Swedish children do not reach the recommended daily activity level. Some, but not all, studies show that extra physical activity may have positive effects on children’s school performance, physical fitness and health. The present purpose was to offer pupils from the 7th to the 8th grade extra aerobic exercise led by physical education teachers and to evaluate the effects on aerobic fitness, muscle strength, school grades and health. The hypothesis was that extra aerobic exercise would improve physical fitness, school grades and health. In the two-year project, 122 pupils aged 13–14 years from three schools constituted an aerobic group with 30 min extra exercise sessions (≥70% maximal heart rate) twice weekly. A control group of 26 pupils was included. All 148 pupils also had regular 60 min physical education lessons (2/week). A moderate to large significant effect size (via partial eta-squared) of the interaction effect for the aerobic group compared to the control group over time was generally seen for aerobic fitness, the muscle strength test with push-ups, school grades in Swedish, English and physical education, and in average school grade for four school subjects combined, thus also including mathematics. Within the aerobic group, significant improvements were also shown for aerobic fitness, endurance and strength of abdominal and leg muscles, and the total physical test index during the two-year project. The control group showed no corresponding improvement in these parameters. Improvements in school grades were generally seen among both sexes in the aerobic group, whereas improvements in physical capacity were distinctly more pronounced among boys and seldom among girls. A similar pattern with significant improvement in several school grades was noted in all three intervention schools, although one of the schools had a distinctly larger proportion of children who immigrated to Sweden. The aerobic group showed significantly higher ratings (with a small to moderate effect size) on several questions about physical self-perception than the control group at the end of the 8th grade. This teacher-led school intervention generated a sustainable project with improvements in physical fitness and school grades. The project might act as an inspiration for other schools to increase physical activity to improve physical fitness and possibly school grades.

Exercise types and working memory components during development

Working memory is crucial to learning and academic success. Exercise has been found to benefit working memory in late life, but its effects during cognitive development are less clear. Building on findings that working memory is supported by the motor system, we highlight the sensitivity of different working memory components to acute and long-term exercise in children and adolescents. We also consider how the specific skill demands of endurance and coordinative exercise influence this sensitivity. Distinct effects of these exercise types are further linked with neurocognitive and neuroendocrine pathways. Our review suggests long-term rather than acute benefits of exercise for children and adolescents' working memory, which are more pronounced and specific for exercise with high coordinative demands.

Aerobic fitness mediates the intervention effects of a school-based physical activity intervention on academic performance. The school in Motion study - A cluster randomized controlled trial

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Physical activity is associated with increased aerobic fitness and academic performance.

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Little is known on mechanism of physical activity effects on academic performance.

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We performed a cluster randomized controlled trial.

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Aerobic fitness mediated the intervention effect on academic performance.

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Activity increasing aerobic fitness is a strategy to improve academic performance.

Little information exists on the mechanism of how physical activity interventions effects academic performance. We examined whether the effects of a school-based physical activity intervention on academic performance were mediated by aerobic fitness. The School in Motion study was a nine-month cluster randomized controlled trial between September 2017 and June 2018. Students from 30 Norwegian lower secondary schools (N = 2,084, mean age [SD] = 14 [0.3] years) were randomly assigned into three groups: the Physically Active Learning (PAL) intervention (n = 10), the Don’t Worry—Be Happy (DWBH) intervention (n = 10), or control (n = 10). Aerobic fitness was assessed by the Andersen test and academic performance by national tests in reading and numeracy. Mediation was assessed according to the causal steps approach using linear mixed models. In the PAL intervention, aerobic fitness partially mediated the intervention effect on numeracy by 28% from a total effect of 1.73 points (95% CI: 1.13 to 2.33) to a natural direct effect of 1.24 points (95% CI: 0.58 to 1.91), and fully mediated the intervention effect on reading, with the total effect of 0.89 points (95% CI: 0.15 to 1.62) reduced to the natural direct effect of 0.40 points (95% CI: −0.48 to 1.28). Aerobic fitness did not mediate the effects on academic performance in the DWBH intervention. As aerobic fitness mediated the intervention effect on academic performance in one intervention, physical activity of an intensity that increases aerobic fitness is one strategy to improve academic performance among adolescents.

Interrelations of Physical Fitness and Cognitive Functions in German Schoolchildren

This study investigated the relationship between different levels of physical fitness and cognitive functions in boys and girls. Schoolchildren from a comprehensive school in Germany (n = 211, 39% girls, 5th and 6th grade) attended regular or sport-focused classes with different numbers of physical education (PE) classes per week (3 vs. 5-6 h). Performance of physical fitness was tested according to endurance, strength, speed, coordination and flexibility. Four computerized instruments (switch task, 2-back task, Corsi block-tapping task and flanker task) were used to test cognitive functions. Additional predictors, sex, age, PE class, Body Mass Index and physical activity, were included in analyses. The results showed that physical fitness was associated with improved attention and memory functions in children, although the associations were mostly small. After Bonferroni correction, mainly coordination was related to improved cognition. Physical activity, i.e., step counts, PE class and sex were associated with specific cognitive outcomes. These findings may be important for effective health promotion, and supporting children's education in the school environment. Sex-specific physical activities in school could potentially lead to greater cognitive benefits in children. Randomized trials are needed to replicate these results.

Measuring resting cerebral haemodynamics using MRI arterial spin labelling and transcranial Doppler ultrasound: Comparison in younger and older adults

INTRODUCTION

Resting cerebral blood flow (CBF) and perfusion measures have been used to determine brain health. Studies showing variation in resting CBF with age and fitness level using different imaging approaches have produced mixed findings. We assess the degree to which resting CBF measures through transcranial Doppler (TCD) and arterial spin labeling (ASL) MRI provide complementary information in older and younger, fit and unfit cohorts.

METHODS

Thirty-five healthy volunteers (20 younger: 24 ± 7y; 15 older: 66 ± 7y) completed two experimental sessions (TCD/MRI). Aging and fitness effects within and between imaging modalities were assessed.

RESULTS

Middle cerebral artery blood velocity (MCAv, TCD) was lower and transit time (MRI) slower in older compared with younger participants (p < .05). The younger group had higher gray matter cerebral perfusion (MRI) than the older group, albeit not significantly (p = .13). Surprisingly, fitness effects in the younger group (decrease/increase in MCAv/transit time with fitness, respectively) opposed the older group (increase/decrease in MCAv/transit time). Whole cohort transit times correlated with MCAv (r=-0.63; p < .05), whereas tissue perfusion did not correlate with TCD measures.

CONCLUSION

TCD and MRI modalities provide complementary resting CBF measures, with similar effects across the whole cohort and between subgroups (age/fitness) if metrics are comparable (e.g., velocity [TCD] versus transit time [MRI]).

Changes in cerebral perfusion following a 12-month exercise and diet intervention

Overweight and obesity may damage the cerebrovascular architecture, resulting in a significant reduction in cerebral blood flow. To date, there have been few randomized clinical trials (RCT) examining whether obesity-related reductions in cerebral blood flow could be modified by weight loss. Further, it is unknown whether the behavioral intervention strategy for weight loss (i.e., diet alone or diet combined with exercise) differentially influences cerebral blood flow in adults with overweight or obesity. The primary aim of this study was to determine whether a 12-month RCT of exercise and diet increases cerebral blood flow in 125 midlife (Mean age ± SD = 44.63 ± 8.36 years) adults with overweight and obesity. Further, we evaluated whether weight loss via diet combined with aerobic exercise has an added effect on changes in cerebral blood flow compared to weight loss via diet alone and whether there were regionally specific effects of the type of behavioral intervention on cerebral blood flow patterns. Consistent with our predictions, a 12-month diet and exercise program resulting in 10% weight loss increased cerebral blood flow. These effects were widespread and extended throughout frontal, parietal, and subcortical regions. Further, there was some regional specificity of effects for both diet-only and diet combined with exercise. Our results demonstrate that weight-related reductions in cerebral blood flow can be modified by 10% weight loss over the course of 12 months and that interventions involving exercise exposure may provide unique effects on cerebral blood flow compared to interventions involving only diet.

Working memory network plasticity after exercise intervention detected by task and resting-state functional MRI

The current study examined the effects of an 11-week exercise intervention on brain activity during a working memory (WM) task and resting-state functional network connectivity in deaf children. Twenty-six deaf children were randomly assigned to either an 11-week exercise intervention or control conditions. Before and after the exercise intervention, all participants were scanned with functional magnetic resonance imaging (fMRI) during N-back task performance and a resting state. The behavioural results showed that the exercise intervention improved WM performance. Task activation analyses showed an increase in the parietal, occipital, and temporal gyri and hippocampus and hippocampus (HIP). In addition, WM performance improvements were associated with greater activation in the left HIP region. Resting-state functional connectivity (Rs-FC) between HIP and certain other brain areas shown a significant interaction of group (exercise versus no exercise) and time (pre- and postintervention). Moreover, connectivity between the left HIP and left middle frontal gyrus was related to improved WM performance. These data extend current knowledge by indicating that an exercise intervention can improve WM in deaf children, and these enhancements may be related to the WM network plasticity changes induced by exercise.

Effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness: A multi-country cluster randomized controlled trial

PURPOSE

To examine the effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness in children aged 7-8 years.

METHODS

Twenty schools in 5 different European countries (2 second-grade classrooms per school) participated in a cluster randomized controlled trial (Sport at School trial). Participants were assigned to either a control group, which continued with their habitual physical education lessons, or to an intervention group, which replaced these lessons with a 1-year karate intervention (Karate Mind and Movement program). A total of 721 children (344 girls and 377 boys, 7.4 ± 0.5 years old, mean ± standard deviation) completed the study, of which 333 and 388 were assigned to the control group and intervention group, respectively. Outcomes included academic performance (average grade), psychosocial functioning (Strengths and Difficulties Questionnaire for parents), and different markers of physical fitness (cardiorespiratory fitness, balance, and flexibility).

RESULTS

The intervention provided small but significant benefits compared to the control group for academic achievement (d = 0.16; p = 0.003), conduct problems (d = -0.28; p = 0.003), cardiorespiratory fitness (d = 0.36; p < 0.001), and balance (d = 0.24; p = 0.015). There was a trend towards significant benefits for flexibility (d = 0.24; p = 0.056). No significant benefits were observed for other variables, including psychosocial difficulties, emotional symptoms, hyperactivity/inattention, peer problems, or prosocial behavior (all p > 0.05).

CONCLUSION

A 1-year school-based karate intervention was effective in improving academic achievement, conduct problems, and physical fitness in primary school children. The results support the inclusion of karate during physical education lessons.

Effects of Physical Exercise Interventions on Spatial Orientation in Children and Adolescents: A Systematic Scoping Review

Background: Regular physical exercise plays an integral part in the psychomotor and psychosocial development of children and adolescents, with complex motor and cognitive processes closely linked. Spatial abilities, one aspect of cognitive functioning start to evolve from earliest childhood and reach adult-like levels by early adolescence. As they have been associated with good spatial orientation, wayfinding, map-reading skills, problem solving or analyzing spatial information, these skills facilitate independence and autonomy while growing up. Despite promising results, only few studies investigate this relation between physical exercise and spatial abilities. To use this benefit and develop purposive physical exercise interventions, it is essential to summarize the current evidence. Objectives: This literature review aims to systematically summarize findings regarding the impact of physical exercise interventions on spatial abilities in healthy children and adolescents and identify knowledge gaps. Methods: A systematic search of the literature according to the PRISMA guidelines was conducted on the databases Pubmed, Web of Science, Cochrane Library, SportDiscus, and PsycInfo from their inception date till March 2021. Additionally, Google Scholar and refence lists of relevant publications were searched. A descriptive analysis of results was conducted. Results: The literature search identified a total of N = 1,215 records, 11 of which met the inclusion criteria and were analyzed in this review. A total of 621 participants aged 4 to 15 years participated in the studies. Exercise interventions included sport-specific activities, motor-coordinative exercises, high-intensity functional training or spatial orientation/navigation training. Five studies evaluated training effects on mental rotation performance (i.e., Mental Rotation Test), four studies investigated visuo-spatial working memory function/spatial memory (i.e., Corsi Block Test, Virtual Reality Morris Water Maze) and two studies tested spatial orientation capacity (i.e., Orientation-Running Test). Overall, results show a potential for improvement of spatial abilities through physical exercise interventions. However, keeping the diversity of study designs, populations and outcomes in mind, findings need to be interpreted with care. Conclusions: Despite growing interest on the effects of physical exercise interventions on spatial abilities and promising findings of available studies, evidence to date remains limited. Future research is needed to establish how spatial ability development of healthy children and adolescents can be positively supported.

Aerobic exercise, cardiorespiratory fitness, and the human hippocampus

The hippocampus is particularly susceptible to neurodegeneration. Physical activity, specifically increasing cardiorespiratory fitness via aerobic exercise, shows promise as a potential method for mitigating hippocampal decline in humans. Numerous studies have now investigated associations between the structure and function of the hippocampus and engagement in physical activity. Still, there remains continued debate and confusion about the relationship between physical activity and the human hippocampus. In this review, we describe the current state of the physical activity and exercise literature as it pertains to the structure and function of the human hippocampus, focusing on four magnetic resonance imaging measures: volume, diffusion tensor imaging, resting-state functional connectivity, and perfusion. We conclude that, despite significant heterogeneity in study methods, populations of interest, and scope, there are consistent positive findings, suggesting a promising role for physical activity in promoting hippocampal structure and function throughout the lifespan.

Understanding the role of aerobic fitness, spatial learning, and hippocampal subfields in adolescent males

Physical exercise during adolescence, a critical developmental window, can facilitate neurogenesis in the dentate gyrus and astrogliogenesis in Cornu Ammonis (CA) hippocampal subfields of rats, and which have been associated with improved hippocampal dependent memory performance. Recent translational studies in humans also suggest that aerobic fitness is associated with hippocampal volume and better spatial memory during adolescence. However, associations between fitness, hippocampal subfield morphology, and learning capabilities in human adolescents remain largely unknown. Employing a translational study design in 34 adolescent males, we explored the relationship between aerobic fitness, hippocampal subfield volumes, and both spatial and verbal memory. Aerobic fitness, assessed by peak oxygen utilization on a high-intensity exercise test (VO2 peak), was positively associated with the volumetric enlargement of the hippocampal head, and the CA1 head region specifically. Larger CA1 volumes were also associated with spatial learning on a Virtual Morris Water Maze task and verbal learning on the Rey Auditory Verbal Learning Test, but not recall memory. In line with previous animal work, the current findings lend support for the long-axis specialization of the hippocampus in the areas of exercise and learning during adolescence.

Do Intervention Studies to Promote Physical Activity and Reduce Sedentary Behavior in Children and Adolescents Take Sex/Gender Into Account? A Systematic Review

BACKGROUND

Physical inactivity is often reported in youth and differs among boys and girls. The aim of this study is to assess sex/gender considerations in intervention studies promoting physical activity and reducing sedentary behavior in youth using a sex/gender checklist.

METHODS

A systematic search was conducted in August 2018 to identify all relevant controlled trials. Studies screened must have reported a quantified measure of physical activity and/or sedentary behavior, and identified participants by sex/gender at baseline. For evaluation of the sex/gender consideration, the authors used a sex/gender checklist developed by expert consensus.

RESULTS

The authors reviewed sex/gender considerations in all aspects of intervention development, implementation, and evaluation in 217 studies. Sex/gender aspects were only rudimentarily taken into account, most frequently during statistical analyses, such as stratification or interaction analysis.

CONCLUSIONS

Sex/gender effects are not sufficiently reported. To develop guidelines that are more inclusive of all girls and boys, future interventions need to document sex/gender differences and similarities, and explore whether sex/gender influences different phases of intervention programs. The newly developed sex/gender checklist can hereby be used as a tool and guidance to adequately consider sex/gender in the several steps of intervention planning, implementation, and evaluation.

Multimodal Imaging Brain Markers in Early Adolescence Are Linked with a Physically Active Lifestyle

The World Health Organization promotes physical exercise and a healthy lifestyle as means to improve youth development. However, relationships between physical lifestyle and human brain development are not fully understood. Here, we asked whether a human brain-physical latent mode of covariation underpins the relationship between physical activity, fitness, and physical health measures with multimodal neuroimaging markers. In 50 12-year old school pupils (26 females), we acquired multimodal whole-brain MRI, characterizing brain structure, microstructure, function, myelin content, and blood perfusion. We also acquired physical variables measuring objective fitness levels, 7 d physical activity, body mass index, heart rate, and blood pressure. Using canonical correlation analysis, we unravel a latent mode of brain-physical covariation, independent of demographics, school, or socioeconomic status. We show that MRI metrics with greater involvement in this mode also showed spatially extended patterns across the brain. Specifically, global patterns of greater gray matter perfusion, volume, cortical surface area, greater white matter extra-neurite density, and resting state networks activity covaried positively with measures reflecting a physically active phenotype (high fit, low sedentary individuals). Showing that a physically active lifestyle is linked with systems-level brain MRI metrics, these results suggest widespread associations relating to several biological processes. These results support the notion of close brain-body relationships and underline the importance of investigating modifiable lifestyle factors not only for physical health but also for brain health early in adolescence.SIGNIFICANCE STATEMENT An active lifestyle is key for healthy development. In this work, we answer the following question: How do brain neuroimaging markers relate with young adolescents' level of physical activity, fitness, and physical health? Combining advanced whole-brain multimodal MRI metrics with computational approaches, we show a robust relationship between physically active lifestyles and spatially extended, multimodal brain imaging-derived phenotypes. Suggesting a wider effect on brain neuroimaging metrics than previously thought, this work underlies the importance of studying physical lifestyle, as well as other brain-body relationships in an effort to foster brain health at this crucial stage in development.

Immediate effects of a single session of physical exercise on cognition and cerebral blood flow: A randomized controlled study of older adults

BACKGROUND

Regular physical activity is beneficial for cognitive performance in older age. A single bout of aerobic physical exercise can transiently improve cognitive performance. Researchers have advanced improvements in cerebral circulation as a mediator of long-term effects of aerobic physical exercise on cognition, but the immediate effects of exercise on cognition and cerebral perfusion are not well characterized and the effects in older adults are largely unknown.

METHODS

Forty-nine older adults were randomized to a 30-min aerobic exercise at moderate intensity or relaxation. Groups were matched on age and cardiovascular fitness (VO2 max). Average Grey Matter Blood Flow (GMBF), measured by a pulsed arterial-spin labeling (pASL) magnetic resonance imaging (MRI) acquisition, and working memory performance, measured by figurative n-back tasks with increasing loads were assessed before and 7 min after exercising/resting.

RESULTS

Accuracy on the n-back task increased from before to after exercising/resting regardless of the type of activity. GMBF decreased after exercise, relative to the control (resting) group. In the exercise group, higher n-back performance after exercise was associated with lower GMBF in the right hippocampus, left medial frontal cortex and right orbitofrontal cortex, and higher cardiovascular fitness was associated with lower GMBF.

CONCLUSION

The decrease of GMBF reported in younger adults shortly after exercise also occurs in older adults and relates to cardiovascular fitness, potentially supporting the link between cardiovascular fitness and cerebrovascular reactivity in older age.

Cardiovascular fitness and structural brain integrity: an update on current evidence

An aging global population and accompanying increases in the prevalence of age-related disorders are leading to greater financial, social, and health burdens. Aging-related dementias are one such category of age-related disorders that are associated with progressive loss of physical and cognitive integrity. One proposed preventative measure against risk of aging-related dementia is improving cardiovascular fitness, which may help reverse or buffer age-related brain atrophy associated with worse aging-related outcomes and cognitive decline. However, research into the beneficial potential of cardiovascular fitness has suffered from extreme heterogeneity in study design methodology leading to a lack of cohesion in the field and undermining any potential causal evidence that may exist. In addition, cardiovascular fitness and exercise are often conflated, leading to a lack of clarity in results. Here, I review recent literature on cardiovascular fitness, brain structure, and aging with the following goals: (a) to disentangle and lay out recent findings specific to aging, cardiovascular fitness, and brain structure, and (b) to ascertain the extent to which causal evidence actually exists. I suggest that, while there is some preliminary evidence for a link between cardiovascular fitness and brain structure in older adults, more research is still needed before definitive causal conclusions can be drawn. I conclude with a discussion of existing gaps in the field and suggestions for how they may be addressed by future research.

The "Fat but Fit" paradox in the academic context: relationship between physical fitness and weight status with adolescents' academic achievement

The present study aimed to analyze the relationship between obesity and different physical fitness markers with academic achievement in adolescents, as well as to check if the "Fat but Fit paradox" is applicable in this context. A total of 188 participants (83 boys) ranging from 12 to 18 years (14.51 ± 1.29 years) underwent a series of fitness tests, and were categorized as "fit" or "unfit" attending to their estimated cardiorespiratory fitness (above or below 42 and 35 ml·kg^-1·min^-1 for boys and girls, respectively). Participants were also categorized according to their body mass index as having overweight/obesity or not. A variety of fitness markers (i.e., cardiorespiratory fitness, lower-body power, sprint time, and flexibility) were positively associated with academic achievement (all p < 0.05), but no associations were found for upper-body power, upper-limb coordination or agility. Both being fit (β = 0.652, 95% confidence interval: 0.001-1.302) and normoweight (β = 1.085, 0.171-1.999) were positively associated with academic achievement. A higher academic achievement (p = 0.021) was found for fit and normoweight individuals compared to unfit and overweight/obese ones, but no differences were found for the remaining subgroups. These findings suggest that an optimal physical fitness might attenuate the negative consequences induced by obesity on academic achievement.

Cardiorespiratory fitness is associated with increased middle cerebral arterial compliance and decreased cerebral blood flow in young healthy adults: A pulsed ASL MRI study

Cardiorespiratory fitness is thought to have beneficial effects on systemic vascular health, in part, by decreasing arterial stiffness. However, in the absence of non-invasive methods, it remains unknown whether this effect extends to the cerebrovasculature. The present study uses a novel pulsed arterial spin labelling (pASL) technique to explore the relationship between cardiorespiratory fitness and arterial compliance of the middle cerebral arteries (MCAC). Other markers of cerebrovascular health, including resting cerebral blood flow (CBF) and cerebrovascular reactivity to CO2 (CVRCO2) were also investigated. Eleven healthy males aged 21 ± 2 years with varying levels of cardiorespiratory fitness (maximal oxygen uptake (V · O2MAX) 38-76 ml/min/kg) underwent MRI scanning at 3 Tesla. Higher V · O2MAX was associated with greater MCAC (R2 = 0.64, p < 0.01) and lower resting grey matter CBF (R2 = 0.75, p < 0.01). However, V · O2MAX was not predictive of global grey matter BOLD-based CVR (R2 = 0.47, p = 0.17) or CBF-based CVR (R2 = 0.19, p = 0.21). The current experiment builds upon the established benefits of exercise on arterial compliance in the systemic vasculature, by showing that increased cardiorespiratory fitness is associated with greater cerebral arterial compliance in early adulthood.

Physical Fitness, Selective Attention and Academic Performance in a Pre-Adolescent Sample

The purpose of the current study is to analyze the relationships between physical fitness, selective attention, and academic performance in pre-teens. The sample here consists of 135 participants between the ages of 10 and 12 (M = 11.05; SD = 0.61), with 39.26% female (n = 53) and 60.74% male (n = 82) participants. Horizontal and vertical jump distances, speed, and cardio-respiratory fitness were evaluated to assess physical fitness. The d2 Test of Attention was used to evaluate selective attention. In addition, data were obtained regarding participant academic performance by analyzing the academic performance. The results show significant relationships between the measures analyzed, highlighting positive associations between physical fitness, cognitive functioning, and academic performance. Thus, participants who were fitter scored better on tests of attention (Z₁₃₃ = −4.07; p < 0.00007, Cohen’s d = 0.75, 95% CI (0.39, 1.11)) and concentration (t₁₃₃ = −3.84; p < 0.0007, Cohen’s d = 0.69, 95% CI (0.33, 1.05)), as well as having higher academic performance (Z₁₃₃ = −2.84; p < 0.0035, Cohen’s d = 0.39, 95% CI (0.04, 0.75)). Cardiorespiratory fitness was the measure of physical fitness that best explained these relationships. The results suggest that maintaining and improving the physical fitness of children and adolescents may help their brain function develop better.

The Roles of Physical Activity, Exercise, and Fitness in Promoting Resilience During Adolescence: Effects on Mental Well-Being and Brain Development

Adolescence is a critical yet vulnerable period for developing behaviors important for mental well-being. The existing literature suggests that physical activity (PA), exercise, and aerobic fitness promote well-being and reduce risk of mental health problems. In this review, we focus on PA, exercise, and fitness as modifiable resilience factors that may help promote self-regulation via strengthening of top-down control of bottom-up processes in the brain, thereby acting as a buffer against mental health problems during this period of vulnerability. First, we briefly review the link between PA, exercise, and aerobic fitness with mental well-being and reduced mental health problems in adolescence. Then we present how impairments in self-regulation, which involves top-down control to modulate bottom-up processes, are common across a wide range of mental health disorders. Finally, we use the extant neuroimaging literature to highlight how neural systems underlying top-down control continue to develop across adolescence, and propose that PA, exercise, and aerobic fitness may facilitate resilience through strengthening individual brain regions as well as large-scale neural circuits to improve emotional and behavioral regulation. Future neuroimaging studies assessing the effects of PA, exercise, and aerobic fitness at various developmental stages in each sex and studies considering the characteristics (e.g., frequency, intensity, type) and social context of PA and exercise are vital to better understand both macro- and microscale mechanisms by which these behaviors and attributes may facilitate mental health resilience during adolescent development.

Assessment of the Effects of Aerobic Fitness on Cerebrovascular Function in Young Adults Using Multiple Inversion Time Arterial Spin Labeling MRI

This cross-sectional study investigated the effects of aerobic fitness on cerebrovascular function in the healthy brain. Gray matter cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) were quantified in a sample of young adults within a normal fitness range. Based on existing Transcranial Doppler ultrasound and fMRI evidence, we predicted a positive relationship between fitness and resting gray matter CBF and CVR. Exploratory hypotheses that higher V . O2peak would be associated with higher GM volume and cognitive performance were also investigated. 20 adults underwent a V . O2peak test and a battery of cognitive tests. All subjects also underwent an MRI scan where multiple inversion time (MTI) pulsed arterial spin labeling (PASL) was used to quantify resting CBF and CVR to 5% CO2. Region of interest analysis showed a non-significant inverse correlation between whole-brain gray matter CBF and V . O2peak; r = -0.4, p = 0.08, corrected p (p') = 0.16 and a significant positive correlation between V . O2peak and whole-brain averaged gray matter CVR; r = 0.62, p = 0.003, p' = 0.006. Voxel-wise analysis revealed a significant inverse association between V . O2peak and resting CBF in the left and right thalamus, brainstem, right lateral occipital cortex, left intra-calcarine cortex and cerebellum. The results of this study suggest that aerobic fitness is associated with lower baseline CBF and greater CVR in young adults.

Effectiveness of Active Learning that Combines Physical Activity and Math in Schoolchildren: A Systematic Review

BACKGROUND

Despite increased interest in combining learning and physical activity (PA), the academic and PA benefits of active learning are uncertain.

METHODS

A systematic search of 5 databases for studies combining learning math with PA in primary/elementary schools was conducted. Academic benefit was evaluated by pre-post intervention math scores compared to a control group. Effect sizes (ES) were extracted/calculated when possible. Due to study heterogeneity, meta-analysis was not conducted.

RESULTS

Six randomized controlled trials and 5 quasi-experimental studies evaluating 4082 participants (53% girls; mean age 7.5-11.1 years) were eligible. Math scores were significantly better in the intervention group in 6 of 11 studies on at least 1 test (ES: 0.42-4.7; p ≤ .03). Other math tests either were not all statistically significant (2 studies) or the benefit varied across grades (1 study). No studies reported a decline in math scores. Of studies measuring PA with accelerometers, 4 of 5 reported significantly greater PA in the intervention group during the intervention (p < .05) or across the school day (p < .01).

CONCLUSIONS

Undertaking PA while learning was largely equivocal for math scores but showed promising results for increasing daily PA, without detrimental effects on math performance. The need for more rigorous studies with comprehensive assessment of academic performance and PA is highlighted.

Physical Fitness Level Is Related to Attention and Concentration in Adolescents

The main goal of this study was to analyze the relationships among physical fitness, selective attention and concentration in a group of 210 teenagers (43.81% male, 56.19% female) from the city of Málaga (Spain), aged between 11 and 15 years old (M = 13.27, SD = 1.80) that participated in the study. D2 attention test was used in order to analyze selective attention and concentration. Physical fitness was evaluated using the horizontal jump test, the Course Navette test and the 5 × 10 meters speed test. The analysis taken indicated a significant relationship among the physical fitness level, the attention and the concentration, as in the general sample as looking at gender. Linear regression tests performed showed that oxygen consumption is the best predictor of attentional parameters. Cluster analysis shows two groups characterized by a greater or lower physical fitness level. So, the highest physical fitness level group scores better in the attention (e.g., boys: p < 0.001, d' Cohen = 1.01, 95% CI [0.57, 1.44]; girls: p < 0.01, d' Cohen = 0.61, 95% CI [0.24, 0.98]) and the concentration tests (e.g., boys: p < 0.001, d' Cohen = 0.89, 95% CI [0.46, 1.32]; girls: p < 0.01, d' Cohen = 0.58, 95% CI [0.21, 0.95]). Results indicate that physical fitness analysis can be used as a tool for observing differences in the attention and concentration level of the analyzed adolescents, suggesting that a physical performance improvement could be an adequate procedure to develop some cognitive functions during adolescence.

Early exercise induces long-lasting morphological changes in cortical and hippocampal neurons throughout of a sedentary period of rats

Life experiences at early ages, such as physical activity in childhood and adolescence, can result in long-lasting brain effects able to reduce future risk of brain disorders and to enhance lifelong brain functions. However, how early physical exercise promotes these effects remains unclear. A possible hypothesis is that physical exercise increases the expression of neurotrophic factors and stimulates neuronal growth, resulting in a neural reserve to be used at later ages. Basing our study on this hypothesis, we evaluated the absolute number and morphology of neuronal cells, as well as the expression of growth, proliferation and survival proteins (BDNF, Akt, mTOR, p70S6K, ERK and CREB) in the cerebral cortex and hippocampal formation throughout of a sedentary period of rats who were physically active during youth. To do this, male Wistar rats were submitted to an aerobic exercise protocol from the 21^st to the 60^th postnatal days (P21–P60), and evaluated at 0 (P60), 30 (P90) and 60 (P120) days after the last exercise session. Results showed that juvenile exercise increased, and maintained elevated, the number of cortical and hippocampal neuronal cells and dendritic arborization, when evaluated at the above post-exercise ages. Hippocampal BDNF levels and cortical mTOR expression were found to be increased at P60, but were restored to control levels at P90 and P120. Overall, these findings indicate that, despite the short-term effects on growth and survival proteins, early exercise induces long-lasting morphological changes in cortical and hippocampal neurons even during a sedentary period of rats.

How Lifestyle Factors Affect Cognitive and Executive Function and the Ability to Learn in Children

In today's research environment, children's diet, physical activity, and other lifestyle factors are commonly studied in the context of health, independent of their effect on cognition and learning. Moreover, there is little overlap between the two literatures, although it is reasonable to expect that the lifestyle factors explored in the health-focused research are intertwined with cognition and learning processes. This thematic review provides an overview of knowledge connecting the selected lifestyle factors of diet, physical activity, and sleep hygiene to children's cognition and learning. Research from studies of diet and nutrition, physical activity and fitness, sleep, and broader influences of cultural and socioeconomic factors related to health and learning, were summarized to offer examples of research that integrate lifestyle factors and cognition with learning. The literature review demonstrates that the associations and causal relationships between these factors are vastly understudied. As a result, current knowledge on predictors of optimal cognition and learning is incomplete, and likely lacks understanding of many critical facts and relationships, their interactions, and the nature of their relationships, such as there being mediating or confounding factors that could provide important knowledge to increase the efficacy of learning-focused interventions. This review provides information focused on studies in children. Although basic research in cells or animal studies are available and indicate a number of possible physiological pathways, inclusion of those data would distract from the fact that there is a significant gap in knowledge on lifestyle factors and optimal learning in children. In a climate where childcare and school feeding policies are continuously discussed, this thematic review aims to provide an impulse for discussion and a call for more holistic approaches to support child development.

Effects of Exercise on Cognitive Performance in Children and Adolescents with ADHD: Potential Mechanisms and Evidence-based Recommendations

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder with a complex symptomatology, and core symptoms as well as functional impairment often persist into adulthood. Recent investigations estimate the worldwide prevalence of ADHD in children and adolescents to be ~7%, which is a substantial increase compared to a decade ago. Conventional treatment most often includes pharmacotherapy with central nervous stimulants, but the number of non-responders and adverse effects call for treatment alternatives. Exercise has been suggested as a safe and low-cost adjunctive therapy for ADHD and is reported to be accompanied by positive effects on several aspects of cognitive functions in the general child population. Here we review existing evidence that exercise affects cognitive functions in children with and without ADHD and present likely neurophysiological mechanisms of action. We find well-described associations between physical activity and ADHD, as well as causal evidence in the form of small to moderate beneficial effects following acute aerobic exercise on executive functions in children with ADHD. Despite large heterogeneity, meta-analyses find small positive effects of exercise in population-based control (PBC) children, and our extracted effect sizes from long-term interventions suggest consistent positive effects in children and adolescents with ADHD. Paucity of studies probing the effect of different exercise parameters impedes finite conclusions in this regard. Large-scale clinical trials with appropriately timed exercise are needed. In summary, the existing preliminary evidence suggests that exercise can improve cognitive performance intimately linked to ADHD presentations in children with and without an ADHD diagnosis. Based on the findings from both PBC and ADHD children, we cautiously provide recommendations for parameters of exercise.

Difference of brain-derived neurotrophic factor expression and pyramid cell count during mastication of food with varying hardness

Previous studies suggested that mastication activity can affect learning and memory function. However, most were focused on mastication impaired models by providing long-term soft diet. The effects of chewing food with various hardness, especially during the growth period, remain unknown.

OBJECTIVE

To analyze the difference of hippocampus function and morphology, as characterized by pyramidal cell count and BDNF expression in different mastication activities.

MATERIALS AND METHODS

28-day old, post-weaned, male-Wistar rats were randomly divided into three groups (n=7); the first (K0) was fed a standard diet using pellets as the control, the second (K1) was fed soft food and the third (K2) was fed hard food. After eight weeks, the rats were decapitated, their brains were removed and placed on histological plates made to count the pyramid cells and quantify BDNF expression in the hippocampus. Data collected were compared using one-way ANOVA.

RESULTS

Results confirmed the pyramid cell count (K0=169.14±27.25; K1=130.14±29.32; K2=128.14±39.02) and BDNF expression (K0=85.27±19.78; K1=49.57±20.90; K2=36.86±28.97) of the K0 group to be significantly higher than that of K1 and K2 groups (p<0.05); no significant difference in the pyramidal cell count and BNDF expression was found between K1 and K2 groups (p>0.05).

CONCLUSION

A standard diet leads to the optimum effect on hippocampus morphology. Food consistency must be appropriately suited to each development stage, in this case, hippocampus development in post-weaned period.