School is an ideal setting to promote and increase physical activity (PA) in children. However, implementation of school-based PA programmes seems difficult, in particular due to schools’ focus on academic performance and a lack of involvement of school staff in program development. The potential cognitive and academic benefits of PA might increase chances of successful implementation. Therefore, the aim of this qualitative study was: (1) to explore the perceptions of teachers and principals with regard to implementation of additional PA aimed at improving cognitive and academic performance, and (2) to identify characteristics of PA programmes that according to them are feasible in daily school practice. Twenty-six face-to-face semi-structured interviews were conducted with primary school teachers (grades 5 and 6) and principals in The Netherlands, and analysed using inductive content analysis. Teachers and principals expressed their willingness to implement additional PA if it benefits learning. Time constraints appeared to be a major barrier, and strongly influenced participants’ perceptions of feasible PA programmes. Teachers and principals emphasised that additional PA needs to be short, executed in the classroom, and provided in “ready-to-use” materials, i.e., that require no or little preparation time (e.g., a movie clip). Future research is needed to strengthen the evidence on the effects of PA for academic purposes, and should examine the forms of PA that are both effective as well as feasible in the school setting.

Omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA) supplementation in the cardiovascular field is effective if a certain Omega-3 index (O3I) is achieved or the daily n-3 LCPUFA dose is high enough. Whether this applies to studies on cognition in children and adolescents is unclear. The aims of the current review were to investigate whether: (1) a certain O3I level and (2) a minimum daily n-3 LCPUFA dose are required to improve cognition in 4–25 year olds. Web of Science and PubMed were searched. Inclusion criteria: placebo controlled randomized controlled trial; participants 4–25 years; supplementation with docosahexaenoic acid (DHA) and/or eicosapentaenoic acid (EPA); assessing cognition; in English and ≥10 participants per treatment arm. Thirty-three studies were included, 21 in typically developing participants, 12 in those with a disorder. A positive effect on cognitive measures was more likely in studies with an increase in O3I to >6%. Half of the studies in typically developing children with daily supplementation dose ≥450 mg DHA + EPA showed improved cognition. For children with a disorder no cut-off value was found. In conclusion, daily supplementation of ≥450 mg DHA + EPA per day and an increase in the O3I to >6% makes it more likely to show efficacy on cognition in children and adolescents.

The current study examined the associations between active commuting to school, cognitive performance, and academic achievement in Dutch adolescents. In addition, it was explored whether these associations were moderated by sex and mediated by depressive symptoms. Students in grades 7 and 9 (N = 270; mean age 13.4 years; 53% boys) were included. Active commuting to school was measured objectively by an ActivPAL3™ accelerometer. Cognitive performance was measured by the d2 Test of attention (key components of executive functioning) and the Symbol Digit Modalities Test (information-processing speed). Academic achievement was determined by the mean of the school grades obtained in Dutch, mathematics and English. Depressive symptoms were self-reported. Active commuting to school constituted 28% of the total amount of time spent moving per week. Active commuting to school was not significantly associated with cognitive performance and academic achievement, overall. However, active commuting to school was positively associated with performance on the d2 Test of attention in girls (β = .17, p = .037), but not in boys (β = −.03, p = .660). The associations were not mediated by depressive symptoms. The associations between active commuting to school and cognitive performance and academic achievement are weak and might be moderated by sex, while the greatest benefits on cognition due to active commuting to school might be with regard to executive functioning. Future studies might make use of experimental designs, because causal relations between active commuting to school and cognitive performance or academic achievement would provide important implications for both education and public health.

Recent evidence on the relationship between omega-3 long chain polyunsaturated fatty acid (n-3 LCPUFA) supplementation and cardiovascular health suggests that n-3 LCPUFA may no longer be efficacious. This review summarises the randomised controlled trials (RCTs) that assess the effect of n-3 LCPUFA supplementation on cardiovascular mortality. It appears that in the RCTs that showed no effect of n-3 LCPUFA on cardiovascular mortality, the dose of n-3 LCPUFA (in particular docosahexaenoic acid (DHA)) and hence the n-3 LCPUFA status, may not have been sufficiently high to demonstrate the efficacy, and/or the baseline n-3 LCPUFA status was already too high. The intention-to-treat analysis (ITT) is the gold standard for analysing RCTs and ITT is used for drug intervention trials where exposure to the drug versus no drug exposure provides two clearly distinct groups to determine the efficacy of the drug being studied. This differs in nutrition trials as often the nutrient of interest being studied is already being consumed by both groups (placebo and active) and therefore a true placebo group with absolutely no intake of the nutrient being studied is highly unlikely. Therefore, in n-3 LCPUFA supplementation trials, as there is no clear distinction between the two groups (placebo and n-3 LCPUFA), a per-protocol analysis (comparison of groups that includes only those participants that fully completed the original intervention allocation) should be conducted in addition to ITT analysis. Furthermore, blood analysis pre- and post-supplementation should be conducted to ensure that: (1) that the baseline n-3 status is not too high, in order to alleviate a potential ceiling effect; and (2) that the dose is high enough and hence the increase in omega-3 status will be high enough in order to assess the efficacy of n-3 LCPUFA supplementation.

Unhealthy lifestyles in early childhood are a major global health challenge. These lifestyles often persist from generation to generation and contribute to a vicious cycle of health-related and social problems. This design article presents a study evaluating the effects of two novel healthy school interventions. The main outcome measure will be changes in children’s body mass index (BMI). In addition, lifestyle behaviours, academic achievement, child well-being, socio-economic differences, and societal costs will be examined. In close collaboration with various stakeholders, a quasi-experimental study was developed, for which children of four intervention schools (n = 1200) in the southern part of the Netherlands are compared with children of four control schools (n = 1200) in the same region. The interventions started in November 2015. In two of the four intervention schools, a whole-school approach named ‘The Healthy Primary School of the Future’, is implemented with the aim of improving physical activity and dietary behaviour. For this intervention, pupils are offered an extended curriculum, including a healthy lunch, more physical exercises, and social and educational activities, next to the regular school curriculum. In the two other intervention schools, a physical-activity school approach called ‘The Physical Activity School’, is implemented, which is essentially similar to the other intervention, except that no lunch is provided. The interventions proceed during a period of 4 years. Apart from the effectiveness of both interventions, the process, the cost-effectiveness, and the expected legal implications are studied. Data collection is conducted within the school system. The baseline measurements started in September 2015 and yearly follow-up measurements are taking place until 2019. A whole-school approach is a new concept in the Netherlands. Due to its innovative, multifaceted nature and sound scientific foundation, these integrated programmes have the potential to form a template for primary schools worldwide. The effects of this approach may extend further than the outcomes associated with well-being and academic achievement, potentially impacting legal and cultural aspects in our society. The study protocol was registered in the database ClinicalTrials.gov on 14-06-2016 with the reference number NCT02800616 .