Katja Jäger

Cognitively Engaging Chronic Physical Activity, But Not Aerobic Exercise, Affects Executive Functions in Primary School Children: A Group-Randomized Controlled Trial

Although the positive effects of different kinds of physical activity (PA) on cognitive functioning have already been demonstrated in a variety of studies, the role of cognitive engagement in promoting childrens executive functions is still unclear. The aim of the current study was therefore to investigate the effects of two qualitatively different chronic PA interventions on executive functions in primary school children. Children (N = 181) aged between 10 and 12 years were assigned to either a 6-week physical education program with a high level of physical exertion and high cognitive engagement (team games), a physical education program with high physical exertion but low cognitive engagement (aerobic exercise), or to a physical education program with both low physical exertion and low cognitive engagement (control condition). Executive functions (updating, inhibition, shifting) and aerobic fitness (multistage 20-m shuttle run test) were measured before and after the respective condition. Results revealed that both interventions (team games and aerobic exercise) have a positive impact on childrens aerobic fitness (4-5% increase in estimated VO2max). Importantly, an improvement in shifting performance was found only in the team games and not in the aerobic exercise or control condition. Thus, the inclusion of cognitive engagement in PA seems to be the most promising type of chronic intervention to enhance executive functions in children, providing further evidence for the importance of the qualitative aspects of PA.

Cognitive and physiological effects of an acute physical activity intervention in elementary school children

The aim of the present study was to investigate the effects of an acute physical activity intervention that included cognitive engagement on executive functions and on cortisol level in young elementary school children. Half of the 104 participating children (6–8 years old) attended a 20-min sport sequence, which included cognitively engaging and playful forms of physical activity. The other half was assigned to a resting control condition. Individual differences in childrens updating, inhibition, and shifting performance as well as salivary cortisol were assessed before (pre-test), immediately after (post-test), and 40 min after (follow-up) the intervention or control condition, respectively. Results revealed a significantly stronger improvement in inhibition in the experimental group compared to the control group, while it appeared that acute physical activity had no specific effect on updating and shifting. The intervention effect on inhibition leveled out 40 min after physical activity. Salivary cortisol increased significantly more in the experimental compared to the control group between post-test and follow-up and results support partly the assumed inverted U-shaped relationship between cortisol level and cognitive performance. In conclusion, results indicate that acute physical activity that includes cognitive engagement may have immediate positive effects on inhibition, but not necessarily on updating and shifting in elementary school children. This positive effect may partly be explained through cortisol elevation after acute physical activity.

Disentangling the relationship between children’s motor ability, executive function and academic achievement

Even though positive relations between children’s motor ability and their academic achievement are frequently reported, the underlying mechanisms are still unclear. Executive function has indeed been proposed, but hardly tested as a potential mediator. The aim of the present study was therefore to examine the mediating role of executive function in the relationship between motor ability and academic achievement, also investigating the individual contribution of specific motor abilities to the hypothesized mediated linkage to academic achievement. At intervals of ten weeks, 236 children aged between 10 and 12 years were tested in terms of their motor ability (t1: cardiovascular endurance, muscular strength, motor coordination), core executive functions (t2: updating, inhibition, shifting), and academic achievement (t3: mathematics, reading, spelling). Structural equation modelling revealed executive function to be a mediator in the relation between motor ability and academic achievement, represented by a significant indirect effect. In separate analyses, each of the three motor abilities were positively related to children’s academic achievement. However, only in the case of children’s motor coordination, the mediation by executive function accounted for a significance percentage of variance of academic achievement data. The results provide evidence in support of models that conceive executive function as a mechanism explaining the relationship that links children’s physical activity-related outcomes to academic achievement and strengthen the advocacy for quality physical activity not merely focused on health-related physical fitness outcomes, but also on motor skill development and learning.

Effekte unterschiedlicher einmaliger Sportinterventionen auf das Arbeitsgedächtnis von Primarschulkindern und der moderierende Effekt von Schulleistung

Korperliche Aktivitat scheint einen positiven Effekt auf die exekutiven Funktionen von Kindern zu haben. Unklar ist jedoch, ob verschiedene Arten von korperlicher Aktivitat die exekutiven Funktionen gleichermasen beeinflussen und ob alle Kinder gleichermasen profitieren. In der vorliegenden Studie wurden verschiedene 20-minutige Interventionen mit variierendem Anteil korperlicher und kognitiver Aktivierung durchgefuhrt. 217 Kinder wurden randomisiert einer von vier Gruppen zugeteilt. Vor und nach den Interventionen wurde die Arbeitsgedachtnisleistung gemessen. Uber die gesamte Stichprobe hinweg konnten keine Interventionseffekte festgestellt werden. Die Schulleistung der Kinder hatte jedoch einen moderierenden Effekt: Wahrend bei Kindern mit tieferer Schulleistung keine Effekte gefunden wurden, verbesserten sich die Kinder mit hoherer Schulleistung durch alle Interventionsbedingungen signifikant starker als durch die Kontrollbedingung. Die fehlenden Effekte in der Gesamtstichprobe werfen die Frage auf, ob es moglicherweise in einem naturlichen Setting und im Gruppenkontext schwieriger ist Effekte zu erzielen als in streng kontrollierten Laborsettings. Zudem weist der selektive Effekt auf das Arbeitsgedachtnis bei Kindern mit hoherer Schulleistung darauf hin, dass nicht alle Kinder gleichermasen von einer Intervention zu profitieren scheinen und moglicherweise individuelle Anpassungen notig sind, um einen allgemeineren positiven Effekt zu erzielen.