Exercise of Varying Durations: No Acute Effects on Cognitive Performance in Adolescents

Participation in structured physical activity is assumed to have a positive effect on cognitive and academic performance. A single bout of moderate to vigorous exercise has been found to have a small acute positive effect on the cognitive performance of children and adolescents. However, the dose-response effects of exercise duration are largely unknown. Therefore, the current study examined the acute effects of moderate-to-vigorous exercise with a duration of either 10, 20, or 30 min on selective attention and working memory performance of young adolescents. One hundred and nineteen adolescents (11–14 years old) participated in a randomized, controlled crossover study. Adolescents were assigned to one of the three exercise durations, each paired with a sedentary control session of the same duration. Cognitive performance was measured before and immediately after the exercise and control condition. The Attention Network Test and n-back task were used to measure selective attention and working memory, respectively. There were no significant exercise effects on selective attention (i.e., alerting, orienting, or executive control) or working memory performance measured immediately after the exercise bouts. Furthermore, there were no differential effects of exercise duration. In sum, acute exercise bouts with a duration of 10, 20, or 30 min did not improve, but neither deteriorate cognitive performance of young adolescents compared to a sedentary control condition.

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title: Acute effects of moderate aerobic exercise on specific aspects of executive function in different age and fitness groups: A meta-analysis.
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title: Effects of physical activity on executive functions, attention and academic performance in preadolescent children: a meta-analysis.
abstract: The aim of this meta-analysis was to provide a systematic review of intervention studies that investigated the effects of physical activity on multiple domains of executive functions, attention and academic performance in preadolescent children (6-12 years of age). In addition, a systematic quantification of the effects of physical activity on these domains is provided.



Systematic review and meta-analysis.



Searches of electronic databases and examining relevant reviews between 2000 and April 2017 resulted in 31 intervention studies meeting the inclusion criteria. Four subdomains of executive functions (inhibition, working memory, cognitive flexibility and planning), three subdomains of attention (selective, divided and sustained) and three subdomains of academic performance (mathematics, spelling and reading) were distinguished. Effects for different study designs (acute physical activity or longitudinal physical activity programs), type of physical activity (aerobic or cognitively engaging) and duration of intervention were examined separately.



Acute physical activity has a positive effect on attention (g=0.43; 95% CI=0.09, 0.77; 6 studies), while longitudinal physical activity programs has a positive effect on executive functions (g=0.24; 95% CI=0.09, 0.39; 12 studies), attention (g=0.90; 95% CI=0.56, 1.24; 1 study) and academic performance (g=0.26; 95% CI=0.02, 0.49; 3 studies). The effects did depend on the subdomain.



Positive effects were found for physical activity on executive functions, attention and academic performance in preadolescent children. Largest effects are expected for interventions that aim for continuous regular physical activity over several weeks.

title: Effect of classroom-based physical activity interventions on academic and physical activity outcomes: a systematic review and meta-analysis
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title: Systematic review of the health benefits of physical activity and fitness in school-aged children and youth
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abstract: To determine the subjective responses of teachers and students to classroom exercise breaks, and how responses varied by duration.



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title: Physical Activity Opportunities during the School Day: Classroom Teachers' Perceptions of Using Activity Breaks in the Classroom.
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title: Implementation of school based physical activity interventions: a systematic review.
abstract: Implementation science is an emerging area in physical activity (PA) research. We sought to establish the current state of the evidence related to implementation of school-based PA models to explore 1) the relationship between implementation and health outcomes, and 2) factors that influence implementation.



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title: Differential effects of differing intensities of acute exercise on speed and accuracy of cognition: A meta-analytical investigation
abstract: The primary purpose of this study was to examine, using meta-analytical techniques, the differential effects of differing intensities of acute exercise on speed and accuracy of cognition. Overall, exercise demonstrated a small, significant mean effect size (g=0.14, p<0.01) on cognition. Examination of the comparison between speed and accuracy dependent variables showed that speed accounted for most of the effect. For speed, moderate intensity exercise demonstrated a significantly larger mean effect size than those for low and high intensities. For speed of processing during moderate intensity exercise, central executive tasks showed a larger effect size than recall and alertness/attention tasks; and mean effect size for counterbalanced or randomized studies was significantly greater than for studies in which a pre-exercise followed by during or post-exercise protocol was used. There was no significant difference between mean effect sizes when testing took place post-exercise compared to during exercise for speed but accuracy studies demonstrated a significantly larger mean effect size post-exercise. It was concluded that increased arousal during moderate intensity exercise resulted in faster speed of processing. The very limited effect on accuracy may be due to the failure to choose tests which are complex enough to measure exercise-induced changes in accuracy of performance.

title: The Acute Effects of Exercise Intensity on Inhibitory Cognitive Control in Adolescents
abstract: Adolescence is an important stage for brain maturation. There are many studies of exercise-cognition relations, but there is still a lack of knowledge about the impact of combining different intensities of exercise on adolescents’ cognitive responses. The main objective of this study was to analyze the effect of three physical education sessions (based on Zumba dance) of different intensities (no exercise, predominantly light intensity, and predominantly vigorous intensity) on the inhibition response (measured with the Stroop test) in adolescents. Forty-four adolescent students (age 16.39 ± 0.68) completed a Stroop test before and after the three different physical education sessions. The results show than the predominantly vigorous session represented the strongest stimulus to increase cognitive inhibitory control. This means that the cognitive effect of exercise can be conditioned by exercise intensity and implies the need to control exercise intensity in physical educational programs for adolescents.

title: Effects of acute bouts of physical activity on children's attention: a systematic review of the literature
abstract: The aim of this review was to describe the effects of acute bouts of physical activity on attention levels of children. A systematic review was performed of English studies from searches in PubMed, Sportdiscus and PsycINFO from 1990 to (May) 2014 according to the PRISMA statement. Only prospective studies of children aged 4-18 years old were included, detailing acute effects of physical activity bouts with the primary outcome attention.One reviewer extracted data on the study characteristics. Two reviewers conducted the methodological quality assessment independently using a criteria checklist, which was based on the Downs and Black checklist for non-randomised studies.Overall the evidence is thin and inconclusive. The methodological differences in study sample (size and age), study design and measurement of attention make it difficult to compare results.There is weak evidence for the effect of acute bouts of physical activity on attention. More experimental studies with a comparable methodology, especially in the school setting, are needed to strengthen this evidence.

title: Physical exercise and executive functions in preadolescent children, adolescents and young adults: a meta-analysis
abstract: The goal of this meta-analysis was to aggregate available empirical studies on the effects of physical exercise on executive functions in preadolescent children (6–12 years of age), adolescents (13–17 years of age) and young adults (18–35 years of age).  The electronic databases PubMed, EMBASE and SPORTDiscus were searched for relevant studies reporting on the effects of physical exercise on executive functions. Nineteen studies were selected.  There was a significant overall effect of acute physical exercise on executive functions (d=0.52, 95% CI 0.29 to 0.76, p<0.001). There were no significant differences between the three age groups (Q (2)=0.13, p=0.94). Furthermore, no significant overall effect of chronic physical exercise (d=0.14, 95%CI −0.04 to 0.32, p=0.19) on executive functions (Q (1)=5.08, p<0.05) was found. Meta-analytic effect sizes were calculated for the effects of acute physical exercise on the domain's inhibition/interference control (d=0.46, 95% CI 0.33 to 0.60, p<0.001) and working memory (d=0.05, 95% CI  −0.51 to 0.61, p=0.86) as well as for the effects of chronic physical exercise on planning (d=0.16, 95% CI 0.18 to 0.89, p=0.18).  Results suggest that acute physical exercise enhances executive functioning. The number of studies on chronic physical exercise is limited and it should be investigated whether chronic physical exercise shows effects on executive functions comparable to acute physical exercise. This is highly relevant in preadolescent children and adolescents, given the importance of well-developed executive functions for daily life functioning and the current increase in sedentary behaviour in these age groups.

title: The effect of acute physical exercise on cognitive function during development
abstract: Although accumulating research suggests that acute physical exercise ameliorates cognitive function in adults, little is known about the effects of acute exercise on cognition during development. We assessed simple reaction and choice response times in 7- and 10-year-old boys ( n  = 36 per age group). Half of the children completed 30 min of aerobic exercise, whilst the other half watched television. Each child was tested immediately prior to and immediately following the intervention. Compared to the control group, the children in the exercise condition showed a significant improvement on both tasks, with a better outcome for the choice compared to the simple task. These findings indicate that physical exercise also has an impact on cognitive functioning in children.

title: Effects of acute aerobic exercise on multiple aspects of executive function in preadolescent children
abstract: The current study assessed the effects of acute exercise on three core executive functions in preadolescents and controlled for the moderating role of age.  A true experimental design.  Thirty-four third-grade children and 53 fifth-grade preadolescents were randomly assigned into either an acute exercise group or a control group. The exercise protocol was designed for ecological validity and involved group jogging at moderate intensity for 30 min. Participants completed inhibition, working memory, and shifting-related executive function tasks prior to and following the treatment.  Acute exercise facilitated performance in three executive function tasks in children in both grade groups; nevertheless, better performance was observed among the fifth graders in inhibition and working memory, but not in shifting, when compared with the third graders.  These findings suggest that acute exercise benefited three primary aspects of executive function in general, regardless of the preadolescent age group, whereas the distinct components of executive function had different developmental trajectories.

title: Effects of varying type of exertion on children's attention capacity.
abstract: The aim of this investigation was to examine the potential influence of varying types of exertion on immediate attentional performance on 138 primary school boys and girls.



Subjects performed three different types of exertion [cognitive exertion (school curricular lesson), physical exertion (traditional physical education lesson), and mixed cognitive and physical exertion (coordinative physical education lesson)] at the same time of the school day for 3 wk. Before and immediately after each exertion session, subjects were administered the d2 Test of Attention.



Results showed that participants' attentional performances were significantly affected by exertion type (cognitive exertion vs physical exertion vs mixed cognitive and physical exertion; P < 0.05), by intervention (before vs after; P < 0.05), and by exertion type × intervention interactions (P < 0.01).



Our findings suggest that varying types of exertion have different beneficial influences on schoolchildren's immediate cognitive performance.

title: Physical activity and mental performance in preadolescents: Effects of acute exercise on free-recall memory
abstract: The purpose of this study was to investigate the effects of physical activity on memory performance in preadolescents. Fifty-two students aged 11–12 years performed a test involving free-recall of items from a 20-item word list during three separate testing sessions at school. Two sessions directly followed physical education lessons (aerobic circuit training or team games) characterized by similar exercise intensities, but different cognitive and social interaction demands. A third, baseline session was not preceded by any lesson. For each session, the number of items recalled from the whole list and from its primacy and recency portions was recorded twice under conditions of immediate and delayed recall. Immediate recall scores in both primacy and recency portions were higher following the team games than in the baseline session, whereas delayed recall scores in the recency portion were higher after both team game and aerobic training. Results suggest that an acute bout of submaximal exercise, as performed by students during physical education class, may facilitate memory storage. The differential effects of qualitatively unique types of exercise on immediate and delayed recall suggest that memory storage processes may be facilitated not only by exercise-induced increases in physiological arousal, but also by the cognitive activation induced by cognitive exercise demands. Results are discussed highlighting the importance of relationships between acute exercise and memory storage for mental health promotion.

title: Investigating links between moderate-to-vigorous physical activity and cognitive performance in elementary school students
abstract: Research has noted both physical and psychological benefits when children participate in physical activity. Recent studies indicate there may also be academic benefits and students may be more efficient learners after physical activity. This study investigated the influence of moderate-to-vigorous physical activity (MVPA) on four cognitive processes: planning, attention, simultaneous processing, and successive processing.  Participants were two classes of fourth-grade students in Ontario ( n  = 40). Using a counterbalanced design, students in the two classes completed standardized tests for each cognitive process both after no physical activity and following it (20 min MVPA within a 45 min lesson).  The results indicate that performance on the planning test significantly improved after physical activity ( p  Planning is associated with problem solving skills and behaviour self-regulation. These skills may be improved in elementary school students immediately following physical activity.

title: A 30‐Minute Physical Education Program Improves Students' Executive Attention
abstract: Physical activity is not only beneficial to physical health but also to cognitive functions. In particular, executive functions that are closely related to learning achievement can be improved by acute and recurring physical activity. We examined the effects of a single 30-min physical education program in contrast to a 5-min movement break on working memory, cognitive flexibility, and inhibition of attention and behavioral tendencies of eighty-one 13- to 14-year-old students in grade 7 in Germany. Results indicate that the maintenance of on-task attention in the face of distraction was improved by an aerobic endurance exercise-based physical education program but not by a short aerobic movement break. This suggests that the duration of a school sports program is decisive for improving students' executive attention.

title: Maintenance of cognitive control during and after walking in preadolescent children.
abstract: The present study evaluated the effects of an acute bout of moderate-intensity treadmill walking on aspects of cognitive control underlying successful academic achievement.



The study used a within-subjects counterbalanced design with a sample of 36 preadolescent children. Cognitive performance was assessed using a modified flanker task and a modified spatial n-back task to assess inhibition and working memory, respectively.



No changes in task performance were observed while individuals were actively walking or at seated rest across both tasks. However, during the flanker task, increased response accuracy was observed after exercise relative to post-seated rest. Further observation revealed decrements to response accuracy after seated rest relative to baseline. No such effect was observed for the n-back task.



These findings suggest selective exercise-induced changes to cognitive control for aspects of inhibitory control and attention but not for working memory. Furthermore, the findings suggest that short bouts of exercise may be efficacious for maintaining cognitive performance, which may have implications for scholastic achievement.

title: Acute exercise facilitates brain function and cognition in children who need it most: An ERP study of individual differences in inhibitory control capacity
abstract: Highlights • Cognitive and ERP assessments were performed following exercise and seated rest.• The sample was bifurcated according to baseline inhibitory control performance.• Selective increases in accuracy and P3 amplitude were observed for lower-performers.• Generalized P3 latency and N2 amplitude changes were observed after exercise.

title: Effects of one versus two bouts of moderate intensity physical activity on selective attention during a school morning in Dutch primary schoolchildren: A randomized controlled trial.
abstract: Evidence suggests that physical activity is positively related to several aspects of cognitive functioning in children, among which is selective attention. To date, no information is available on the optimal frequency of physical activity on cognitive functioning in children. The current study examined the acute effects of one and two bouts of moderate-intensity physical activity on children's selective attention.



Randomized controlled trial (ISRCTN97975679).



Thirty boys and twenty-six girls, aged 10-13 years, were randomly assigned to three conditions: (A) sitting all morning working on simulated school tasks; (B) one 20-min physical activity bout after 90min; and (C) two 20-min physical activity bouts, i.e. at the start and after 90min. Selective attention was assessed at five time points during the morning (i.e. at baseline and after 20, 110, 130 and 220min), using the 'Sky Search' subtest of the 'Test of Selective Attention in Children'. We used GEE analysis to examine differences in Sky Search scores between the three experimental conditions, adjusting for school, baseline scores, self-reported screen time and time spent in sports.



Children who performed two 20-min bouts of moderate-intensity physical activity had significantly better Sky Search scores compared to children who performed one physical activity bout or remained seated the whole morning (B=-0.26; 95% CI=[-0.52; -0.00]).



Our findings support the importance of repeated physical activity during the school day for beneficial effects on selective attention in children.

title: Physical fitness, but not acute exercise modulates event-related potential indices for executive control in healthy adolescents
abstract: Physical activity and aerobic exercise in particular, promotes health and effective cognitive functioning. To elucidate mechanisms underlying the beneficial effects of physical fitness and acute exercise, behavioral and electrophysiological indices of task preparation and response inhibition as a part of executive functions were assessed in a modified version of an Eriksen flanker task subsequent to an acute bout of aerobic exercise and a period of rest, respectively. 35 higher- and lower-fit adolescents between 13 and 14 years of age participated in a controlled cross-over study design. Results indicate that higher-fit individuals show significantly greater CNV amplitudes, reflecting enhanced task preparation processes, as well as decreased amplitudes in N2, indexing more efficient executive control processes. P3 amplitudes associated with the allocation of attentional and memory control neither showed influences of physical fitness nor the acute bout of exercise. Furthermore, acute aerobic exercise was not related to any of the dependent measures. The current findings suggest that physical fitness, but not an acute bout of aerobic exercise enhances cognitive processing by increasing attentional allocation to stimulus encoding during task preparation.

title: Acute Effects of Classroom Exercise Breaks on Executive Function and Math Performance: A Dose–Response Study
abstract: The purpose of this study was to determine the acute dose–response relationship of classroom exercise breaks with executive function and math performance in 9- to 12-year-old children by comparing 5-min, 10-min, or 20-min classroom exercise breaks to 10 min of sedentary classroom activity.  This study used a within-subjects experimental design conducted in the spring of 2012. Ninety-six 4th- and 5th-grade students in 5 classrooms in South Carolina were randomized to receive each of 4 treatments: 5-min, 10-min, or 20-min exercise breaks or 10 min of a sedentary lesson led by research staff. Students completed the Trail-Making Test, an Operational Digit Recall test, and a math fluency test immediately before and after each condition. Planned linear contrasts were used to compare posttest scores between conditions using a repeated-measures mixed model, adjusted for gender, classroom, and the time-varying pretest scores. Potential effect modifiers were added as interaction terms.  Math scores were higher after the 10-min and 20-min exercise breaks compared with the sedentary condition (d = 0.24, p = .04, and d = 0.27, p = .02, respectively), and an interaction was observed with gender, IQ, aerobic fitness, and lower engagement in some of the conditions. There were no improvements in executive function tasks.  A 10-min and 20-min classroom exercise break moderately improved math performance in students compared with a seated classroom lesson.

title: Acute coordinative exercise improves attentional performance in adolescents
abstract: Teachers complain about growing concentration deficits and reduced attention in adolescents. Exercise has been shown to positively affect cognitive performance. Due to the neuronal connection between the cerebellum and the frontal cortex, we hypothesized that cognitive performance might be influenced by bilateral coordinative exercise (CE) and that its effect on cognition might be already visible after short bouts of exercise. One hundred and fifteen healthy adolescents aged 13-16 years of an elite performance school were randomly assigned to an experimental and a control group and tested using the d2-test, a test of attention and concentration. Both groups performed the d2-test after a regular school lesson (pre-test), after 10 min of coordinative exercise and of a normal sport lesson (NSL, control group), respectively (post-test). Exercise was controlled for heart rate (HR). CE and NSL enhanced the d2-test performance from pre- to post-test significantly. ANOVA revealed a significant group (CE, NSL) by performance interaction in the d2-test indicating a higher improvement of CE as compared to NSL. HR was not significantly different between the groups. CE was more effective in completing the concentration and attention task. With the HR being the same in both groups we assume that the coordinative character of the exercise might be responsible for the significant differences. CE might lead to a pre-activation of parts of the brain which are also responsible for mediating functions like attention. Thus, our results support the request for more acute CE in schools, even in elite performance schools.

title: Influence of acute and chronic physical activity on cognitive performance and saliva testosterone in preadolescent school children
abstract: We investigated whether the chronic physical activity participation had an impact on the acute effects of a short bout of 12 min of intensive physical activity on cognitive performance and testosterone concentration in primary school students ( n  = 42, mean age = 9.69, SD = .44; experimental group (EG), n  = 27; control group (CG), n  = 15). Furthermore, we looked for associations between testosterone concentration and cognitive performance. After the intervention, participants of the EG showed better cognitive performances as compared to the CG. We further observed a significant group (EG, CG) × test (pre, post) × activity level (high, low) interaction. Post hoc pairwise comparisons revealed that after acute physical activity the testosterone concentration was diminished only in habitually low active children. The results indicate that intensive physical activity only attenuates the reactivity of the hypothalamic-pituitary-gonadal axis in habitually low active preadolescents, but had a beneficial effect on cognitive performance for all participants independent of their physical activity level and testosterone.

title: A short physical activity break from cognitive tasks increases selective attention in primary school children aged 10–11
abstract: Importance Evidence for an acute effect of physical activity on cognitive performance within the school setting is limited. The purpose of this study was to gain insight into acute effects of a short physical activity bout on selective attention in primary school children, specifically in the school setting.  Hundred and twenty three 10–11 years old children, 49.6% girls, engaged in four experimental breaks in random order: 1 h of regular cognitive school tasks followed by a 15 min episode with the following conditions 1) ‘no break’ (continuing a cognitive task), 2) passive break (listening to a story), 3) moderate intensity physical activity break (jogging, passing, dribbling) and 4) vigorous intensity physical activity break (running, jumping, skipping). Selective attention in the classroom was assessed by the TEA-Ch test before and after the 15 min break in each condition.  After the passive break, the moderate intensity physical activity break and the vigorous intensity physical activity break attention scores were significantly better ( p  The results show a significant positive effect of both a passive break as well as a physical activity break on selective attention, with the largest effect of a moderate intensity physical activity break. This suggests that schools could implement a moderate intensity physical activity break during the school day to optimize attention levels and thereby improve school performance.

title: Steroid hormones in the saliva of adolescents after different exercise intensities and their influence on working memory in a school setting
abstract: Little is known, about the influence of different exercise intensities on cognition, the concentration of steroid hormones (SHs), and their interaction in adolescents. Sixty high school students from the 9th grade were randomly assigned to two experimental (EG 1, EG 2) and a control group (CG). Saliva collection took place after a normal school lesson (t1) and after a 12-min resting control or exercise (t2) in a defined heart rate (HR) interval (EG 1: 50-65% HR max, n=18; EG 2: 70-85% HR max, n=20; CG: no intervention, n=21). Saliva was analyzed for T and C. Cognitive performance was assessed using a working memory task (Letter Digit Span; LDS), which took place after t1 and t2. Repeated measure ANOVAs revealed a significant group by test interaction, indicating an increase of C and T level only for EG 2. Results for LDS showed a significant improvement due to exercise when groups were split into low and high performer at pre-test with a higher improvement of the low performers. In addition, post-test T levels negatively correlated with changes in LDS performance in EG 2. The results indicate that the concentrations of C and T are intensity dependent, and that exercise improves working memory in low performing adolescents. Only increased T, however, seems to be related to pre-to-post-test changes in working memory by having a detrimental effect on performance.

title: The effects of a mid-morning bout of exercise on adolescents' cognitive function
abstract: The aim of the present study was to examine the effects of a mid-morning bout of exercise on adolescents' cognitive function in a randomised crossover design where each participant completed two experimental trials. Forty-five adolescents (13.3 ± 0.3 years old), undertook a bout of exercise (ten repeats of level one of the multi-stage fitness test, 30 s rest between repeats; exercise trial) or continued to rest (resting trial). A battery of cognitive function tests assessing visuo-motor speed, executive function and working memory (visual search test, Stroop test and Sternberg paradigm, respectively) was completed 30 min before and 45 min following the exercise. Average heart rate during exercise was 172 ± 17 beats min − 1 . On the visual search test, there was a greater improvement in response times across the morning on the exercise trial ( t  = 2.6, p  = 0.009). However, this improvement in response times was combined with a greater decrease in accuracy on the exercise trial ( z  = 2.0, p  = 0.044). On the Sternberg paradigm there was a greater improvement in response times across the morning following exercise when compared to resting ( t  = 2.6, p  = 0.010). The mid-morning bout of exercise did not affect Stroop test performance. These improvements in response times are most likely the result of a general speeding up of responses across several cognitive domains, because response times were improved similarly across two different domains and across all test complexity levels, rather than being restricted to the specific high cognitive load levels. Accordingly, exercise in school settings may help to improve cognitive function in adolescents during the school morning.

title: Sprint-based exercise and cognitive function in adolescents
abstract: Moderate intensity exercise has been shown to enhance cognition in an adolescent population, yet the effect of high-intensity sprint-based exercise remains unknown and was therefore examined in the present study. Following ethical approval and familiarisation, 44 adolescents (12.6 ± 0.6 y) completed an exercise (E) and resting (R) trial in a counter-balanced, randomised crossover design. The exercise trial comprised of 10 × 10 s running sprints, interspersed by 50 s active recovery (walking). A battery of cognitive function tests (Stroop, Digit Symbol Substitution (DSST) and Corsi blocks tests) were completed 30 min pre-exercise, immediately post-exercise and 45 min post-exercise. Data were analysed using mixed effect models with repeated measures. Response times on the simple level of the Stroop test were significantly quicker 45 min following sprint-based exercise (R: 818 ± 33 ms, E: 772 ± 26 ms; p = 0.027) and response times on the complex level of the Stroop test were quicker immediately following the sprint-based exercise (R: 1095 ± 36 ms, E: 1043 ± 37 ms; p = 0.038), while accuracy was maintained. Sprint-based exercise had no immediate or delayed effects on the number of items recalled on the Corsi blocks test (p = 0.289) or substitutions made during the DSST (p = 0.689). The effect of high intensity sprint-based exercise on adolescents' cognitive function was dependant on the component of cognitive function examined. Executive function was enhanced following exercise, demonstrated by improved response times on the Stroop test, whilst visuo-spatial memory and general psycho-motor speed were unaffected. These data support the inclusion of high-intensity sprint-based exercise for adolescents during the school day to enhance cognition.

title: The impact of 10‐minute activity breaks outside the classroom on male students’ on‐task behaviour and sustained attention: a randomised crossover design
abstract: The aim was to evaluate the impact of a brief activity bout outside the classroom on boys’ attention and on‐task behaviour in the classroom setting.

title: Acute classroom exercise breaks improve on-task behavior in 4th and 5th grade students: A dose-response
abstract: This study was the first to directly compare the acute effects of 5, 10, and 20 min of classroom exercise breaks on on-task behavior.  In this within-subject experiment, 96 4th and 5th grade students, in 5 classroom groups, participated in each of four conditions: 10 min of sedentary classroom activity and 5, 10, 20 min of classroom exercise breaks led by research staff. On-task behavior was directly and systematically observed from videotapes before and after each condition. The post-test time-on-task scores were compared using a repeated measures mixed ANCOVA, adjusted for age, classroom, and the time-varying pre-test time-on-task.  Time-on-task was significantly higher in students after 10 min of classroom exercise breaks compared to a sedentary attention control (87.6% vs 77.1%, d = .45, p = .004).  Ten minutes of classroom exercise breaks improved on-task behavior in children.

title: Dose-response relation between exercise duration and cognition.
abstract: The study aimed to provide evidence-based recommendations for the prescription of a single session of exercise to improve cognitive performance. In particular, the purpose was to determine the dose-response relation between exercise duration and cognitive performance for a moderate-intensity session of aerobic exercise.



Twenty-six healthy young men participated in a reading control treatment and three exercise treatments presented in a random order. The exercise treatments were designed on the basis of the American College of Sports Medicine guidelines and consisted of a 5-min warm-up, a 5-min cooldown, and cycling at moderate intensity (approximately 65% HR reserve) for 10, 20, or 45 min. The Stroop test was administrated after completion of each assigned treatment.



Exercise at moderate intensity for 20 min resulted in significantly better cognitive performance, as assessed by shorter response time and higher accuracy. This result was found regardless of the type of cognitive function assessed. In addition, a curvilinear dose-response relation between exercise duration and cognitive performance was observed.



An exercise session consisting of a 5-min warm-up, 20 min of moderate-intensity exercise, and a 5-min cooldown improves cognition, whereas shorter or longer durations of moderate exercise have negligible benefits. This study provides the foundation for the prescription of a single session of moderate exercise to facilitate cognitive function in healthy younger adults.

title: The role of selective attention on academic foundations: A cognitive neuroscience perspective
abstract: To the extent that selective attention skills are relevant for academic foundations and amenable to training, they represent an important focus for the field of education. Here, drawing on research on the neurobiology of attention, we review hypothesized links between selective attention and processing across three domains important to early academic skills. First, we provide a brief review of the neural bases of selective attention, emphasizing the effects of selective attention on neural processing, as well as the neural systems important to deploying selective attention and managing response conflict. Second, we examine the developmental time course of selective attention. It is argued that developmental differences in selective attention are related to the neural systems important for deploying selective attention and managing response conflict. In contrast, once effectively deployed, selective attention acts through very similar neural mechanisms across ages. In the third section, we relate the processes of selective attention to three domains important to academic foundations: language, literacy, and mathematics. Fourth, drawing on recent literatures on the effects of video-game play and mind-brain training on selective attention, we discuss the possibility of training selective attention. The final section examines the application of these principles to educationally-focused attention-training programs for children.

title: Visuospatial working memory and mathematical ability at different ages throughout primary school
abstract: In this study, three aims were addressed: (1) validating a visuospatial working memory task in Math Garden, an adaptive online tool in which item difficulty and person ability are determined on the fly, (2) investigating the contribution of different item characteristics to the difficulty of the visuospatial working memory items, and (3) investigating relations between visuospatial working memory and various math domains at different ages. The method was validated by showing that item ratings were stable and grade differences in ability were significant. Regression analyses on the item level showed that not only sequence length, but also other characteristics, such as type of task (forward or backward), explained variance in item difficulty. Finally, regression analyses on the child level showed that visuospatial working memory and mathematics were significantly related: especially for addition and subtraction in the lower grades. For multiplication and division this relationship was weaker and without age trend.

title: Working memory: looking back and looking forward
abstract: The concept of working memory proposes that a dedicated system maintains and stores information in the short term, and that this system underlies human thought processes. Current views of working memory involve a central executive and two storage systems: the phonological loop and the visuospatial sketchpad. Although this basic model was first proposed 30 years ago, it has continued to develop and to stimulate research and debate. The model and the most recent results are reviewed in this article.

title: The multistage 20 metre shuttle run test for aerobic fitness.
abstract: A maximal multistage 20 m shuttle run test was designed to determine the maximal aerobic power of schoolchildren, healthy adults attending fitness class and athletes performing in sports with frequent stops and starts (e.g. basketball, fencing and so on). Subjects run back and forth on a 20 m course and must touch the 20 m line; at the same time a sound signal is emitted from a prerecorded tape. Frequency of the sound signals is increased 0.5 km h-1 each minute from a starting speed of 8.5 km h-1. When the subject can no longer follow the pace, the last stage number announced is used to predict maximal oxygen uptake (VO2max) (Y, ml kg-1 min-1) from the speed (X, km h-1) corresponding to that stage (speed = 8 + 0.5 stage no.) and age (A, year): Y = 31.025 + 3.238 X - 3.248A + 0.1536AX, r = 0.71 with 188 boys and girls aged 8-19 years. To obtain this regression, the test was performed individually. Right upon termination VO2 was measured with four 20 s samples and VO2max was estimated by retroextrapolating the O2 recovery curve at time zero of recovery. For adults, similar measurements indicated that the same equation could be used keeping age constant at 18 (r = 0.90, n = 77 men and women 18-50 years old). Test-retest reliability coefficients were 0.89 for children (139 boys and girls 6-16 years old) and 0.95 for adults (81 men and women, 20-45 years old).(ABSTRACT TRUNCATED AT 250 WORDS)

title: The Relation of Brain Oscillations to Attentional Networks
abstract: Previous studies have suggested the relation of particular frequency bands such as theta (4–8 Hz), alpha (8–14 Hz), beta (14–30 Hz), or gamma (>30 Hz) to cognitive functions. However, there has been controversy over which bands are specifically related to attention. We used the attention network test to separate three anatomically defined brain networks that carry out the functions of alerting, orienting, and executive control of attention. High-density scalp electrical recording was performed to record synchronous oscillatory activity and power spectrum analyses based on functional magnetic resonance imaging constrained dipole modeling were conducted for each attentional network. We found that each attentional network has a distinct set of oscillations related to its activity. The alerting network showed a specific decrease in theta-, alpha-, and beta-band activity 200–450 ms after a warning signal. The orienting network showed an increase in gamma-band activity at ∼200 ms after a spatial cue, indicating the location of a target. The executive control network revealed a complex pattern when a target was surrounded with incongruent flankers compared with congruent flankers. There was an early (<400 ms) increase in gamma-band activity, a later (>400 ms) decrease in beta- and low gamma-band activity after the target onset, and a decrease of all frequency bands before response followed by an increase after the response. These data demonstrate that attention is not related to any single frequency band but that each network has a distinct oscillatory activity and time course.

title: Testing the Efficiency and Independence of Attentional Networks
abstract: In recent years, three attentional networks have been defined in anatomical and functional terms. These functions involve alerting, orienting, and executive attention. Reaction time measures can be used to quantify the processing efficiency within each of these three networks. The Attention Network Test (ANT) is designed to evaluate alerting, orienting, and executive attention within a single 30-min testing session that can be easily performed by children, patients, and monkeys. A study with 40 normal adult subjects indicates that the ANT produces reliable single subject estimates of alerting, orienting, and executive function, and further suggests that the efficiencies of these three networks are uncorrelated. There are, however, some interactions in which alerting and orienting can modulate the degree of interference from flankers. This procedure may prove to be convenient and useful in evaluating attentional abnormalities associated with cases of brain injury, stroke, schizophrenia, and attention-deficit disorder. The ANT may also serve as an activation task for neuroimaging studies and as a phenotype for the study of the influence of genes on attentional networks.

title: The effect of acute treadmill walking on cognitive control and academic achievement in preadolescent children
abstract: The effect of an acute bout of moderate treadmill walking on behavioral and neuroelectric indexes of the cognitive control of attention and applied aspects of cognition involved in school-based academic performance were assessed. A within-subjects design included 20 preadolescent participants (age=9.5+/-0.5 years; eight female) to assess exercise-induced changes in performance during a modified flanker task and the Wide Range Achievement Test 3. The resting session consisted of cognitive testing followed by a cardiorespiratory fitness assessment to determine aerobic fitness. The exercise session consisted of 20 min of walking on a motor-driven treadmill at 60% of estimated maximum heart rate followed by cognitive testing once heart rate returned to within 10% of pre-exercise levels. Results indicated an improvement in response accuracy, larger P3 amplitude, and better performance on the academic achievement test following aerobic exercise relative to the resting session. Collectively, these findings indicate that single, acute bouts of moderately-intense aerobic exercise (i.e. walking) may improve the cognitive control of attention in preadolescent children, and further support the use of moderate acute exercise as a contributing factor for increasing attention and academic performance. These data suggest that single bouts of exercise affect specific underlying processes that support cognitive health and may be necessary for effective functioning across the lifespan.

title: The effects of acute exercise on cognitive performance: A meta-analysis
abstract: There is a substantial body of literature related to the effects of a single session of exercise on cognitive performance. The premise underlying this research is that physiological changes in response to exercise have implications for cognitive function. This literature has been reviewed both narratively and meta-analytically and, although the research findings are mixed, researchers have generally concluded that there is a small positive effect. The purpose of this meta-analysis was to provide an updated comprehensive analysis of the extant literature on acute exercise and cognitive performance and to explore the effects of moderators that have implications for mechanisms of the effects. Searches of electronic databases and examinations of reference lists from relevant studies resulted in 79 studies meeting inclusion criteria. Consistent with past findings, analyses indicated that the overall effect was positive and small (g=0.097 n=1034). Positive and small effects were also found in all three acute exercise paradigms: during exercise (g=0.101; 95% confidence interval [CI]; 0.041-0.160), immediately following exercise (g=0.108; 95% CI; 0.069-0.147), and after a delay (g=0.103; 95% CI; 0.035-0.170). Examination of potential moderators indicated that exercise duration, exercise intensity, type of cognitive performance assessed, and participant fitness were significant moderators. In conclusion, the effects of acute exercise on cognitive performance are generally small; however, larger effects are possible for particular cognitive outcomes and when specific exercise parameters are used.

title: Executive function during and after acute moderate aerobic exercise in adolescents
abstract: In two experiments, we investigated the effects of acute moderate-intensity exercise on aspects of executive function in adolescents.  An experimental design was used.  Fifty-five Japanese adolescents (Experiment 1: N ¼ 28; Experiment 2: N ¼ 27) performed a modified flanker task and a modified n-back task to assess inhibitory control and working memory before, during, and after walking on a treadmill at moderate intensity (Experiment 1: 60% maximal heart rate; Experiment 2: 70% maximal heart rate). In a separate session, the same testing sequence was administered while participants sat in a chair.  The results revealed that reaction time for working memory increased during exercise in both experiments, while response accuracy decreased during exercise only at 70% maximal heart rate. Moderate intensity exercise had no substantial effect on inhibition control. Following cessation of the exercise, no effects were observed for either executive function assessment.  These results indicate that moderate intensity exercise selectively affects executive function in adolescents. Further, during physical activity, adolescents maintain inhibitory control, but their working memory declines. Further research is required to reveal the mechanisms underlying this phenomenon and to expand beyond the laboratory setting to the areas of sports and physical activities of daily living.

title: Exercise and Cognitive Function: Time Course of the Effects
abstract: Previous research has indicated a variable effect of exercise on adolescents’ cognitive function. However, comparisons between studies are difficult to make due to differences in: the mode, intensity and duration of exercise employed; the components of cognitive function measured (and the tests used to assess them); and the timing of the cognitive function tests in relation to the exercise. Therefore, the aim of the present study was to assess the time course (10 and 60min post-exercise) of the effects of 15min intermittent exercise on cognitive function in adolescents. 45 adolescents were recruited to participate in the study and completed two main trials (exercise and resting) in a counterbalanced crossover design. Participants completed 15min of intermittent exercise (in cycles of 1 min exercise, 30s rest). A battery of computer based cognitive function tests (Stroop test, Sternberg paradigm and visual search test) were completed 30 min preand 10 and 60min post-exercise (to assess attention, working memory and perception respectively).The findings of the present study indicate that on the baseline level of the Stroop test, 10min following exercise response times were slower than at any other time point on either trial (trial by session time interaction, p = 0.0308). However, this slowing of responses also tended to produce enhanced accuracy 10min post-exercise on the baseline level of the Stroop test (trial by session time interaction, p = 0.0780). Similarly, on the complex level of the visual search test there was a slowing of response times 10 min post-exercise (trial by session time interaction, p = 0.0199). However, this was not coupled with an improvement in accuracy (trial by session time interaction, p = 0.2349). The mid-morning bout of exercise did not affect response times or accuracy across the morning on the Sternberg paradigm. In conclusion, the findings of the present study suggest an equivocal effect of exercise on adolescents' cognitive function. The midmorning bout of exercise appears to cause a speed-accuracy trade off immediately following exercise on the Stroop test (participants become slower but more accurate), whilst slowing response times on the visual search test and having no effect on performance on the Sternberg paradigm. Furthermore, this work highlights the importance of the timing of the cognitive function tests relative to the exercise and the components of cognitive function examined in future studies. Adolescents, cognitive function, exercise.

title: Improving fluid intelligence with training on working memory
abstract: Fluid intelligence (Gf) refers to the ability to reason and to solve new problems independently of previously acquired knowledge. Gf is critical for a wide variety of cognitive tasks, and it is considered one of the most important factors in learning. Moreover, Gf is closely related to professional and educational success, especially in complex and demanding environments. Although performance on tests of Gf can be improved through direct practice on the tests themselves, there is no evidence that training on any other regimen yields increased Gf in adults. Furthermore, there is a long history of research into cognitive training showing that, although performance on trained tasks can increase dramatically, transfer of this learning to other tasks remains poor. Here, we present evidence for transfer from training on a demanding working memory task to measures of Gf. This transfer results even though the trained task is entirely different from the intelligence test itself. Furthermore, we demonstrate that the extent of gain in intelligence critically depends on the amount of training: the more training, the more improvement in Gf. That is, the training effect is dosage-dependent. Thus, in contrast to many previous studies, we conclude that it is possible to improve Gf without practicing the testing tasks themselves, opening a wide range of applications.

title: Systematic review of acute physically active learning and classroom movement breaks on children’s physical activity, cognition, academic performance and classroom behaviour: understanding critical design features
abstract: To examine the impact of acute classroom movement break (CMB) and physically active learning (PAL) interventions on physical activity (PA), cognition, academic performance and classroom behaviour.  Data sources PubMed, EBSCO, Academic Search Complete, Education Resources Information Center, PsycINFO, SPORTDiscus, SCOPUS and Web of Science.   Ten PAL and eight CMB studies were identified from 2929 potentially relevant articles. Risk of bias scores ranged from 33% to 64.3%. Variation in study designs drove specific, but differing, outcomes. Three studies assessed PA using objective measures. Interventions replaced sedentary time with either light PA or moderate-to-vigorous PA dependent on design characteristics (mode, duration and intensity). Only one study factored individual PA outcomes into analyses. Classroom behaviour improved after longer moderate-to-vigorous (>10 min), or shorter more intense (5 min), CMB/PAL bouts (9 out of 11 interventions). There was no support for enhanced cognition or academic performance due to limited repeated studies.  Low-to-medium quality designs predominate in investigations of the acute impacts of CMB and PAL on PA, cognition, academic performance and classroom behaviour. Variable quality in experimental designs, outcome measures and intervention characteristics impact outcomes making conclusions problematic. CMB and PAL increased PA and enhanced time on task. To improve confidence in study outcomes, future investigations should combine examples of good practice observed in current studies. PROSPERO registration number CRD42017070981.

title: Estimated energy expenditures for school-based policies and active living.
abstract: Despite overwhelming evidence of the health benefits of physical activity, most American youth are not meeting the 60 minutes per day recommendation for moderate- to vigorous-intensity physical activity (MVPA). Policy changes have the potential to bring about substantial increases in physical activity in youth, within school and community settings.



The purpose of this study was to quantify the increase in energy expenditure for school-based policies and built environment changes.



Scientific literature reviews were consulted, and more than 300 published studies (1995-2011) in English were identified based on titles and abstracts. After an initial screening, 85 articles were included. Study quality was assessed, and the impact of various strategies for increasing physical activity in youth was estimated from objective measurements/direct observation.



Within school settings, the average minutes of MVPA gained per school day for studies in each intervention category were as follows: mandatory physical education (23 minutes); classroom activity breaks (19 minutes); afterschool activity programs (10 minutes); standardized physical education curricula (6 minutes more than traditional physical education); modified playgrounds (6 minutes); and modified recess (5 minutes more than traditional recess). Within community settings, significant MVPA was associated with active commuting (16 minutes) and park renovations (12 minutes), but proximity to parks had a small effect (1 minute). No conclusions could be drawn regarding joint-use agreements, because of a lack of studies quantifying their impact on energy expenditure.



Of the various policies and built environment changes examined, the largest effects were seen with mandatory physical education, classroom activity breaks, and active commuting to school. Policymakers can use this information along with estimates of the cost, feasibility, and population reach, to identify the best options for increasing physical activity in youth.