ObjectivesTo evaluate the effect of a 20-week school-based physical activity intervention program on academic performance and selective attention among disadvantaged South African primary school children.DesignCluster randomized control trial.MethodsThe study cohort included 663 children from eight primary schools, aged 8–13 years. Data assessment took place between February 2015 and May 2016 following the implementation of a 20-week school-based physical activity program. The d2 test was employed to assess selective attention, while the averaged end-of-year school results (math, life skills, home language, and additional language) were used as an indicator of academic performance. Physical fitness was assessed using the 20-m shuttle run test (VO2 max) and grip strength tests. We controlled for cluster effects, baseline scores in selective attention or academic performance, and potential confounders, such as children’s age, gender, socioeconomic status, self-reported physical activity (as determined by a pre-tested questionnaire), body mass index, hemoglobin (as a proxy for anemia, as measured by blood sampling), and soil-transmitted helminth infections (as assessed by the Kato-Katz technique).ResultsOur multivariate analysis suggested that the physical activity intervention had a positive effect on academic performance (p = 0.032), while no effect was found on selective attention (concentration performance; p = 0.469; error percentage; p = 0.237). After controlling for potential confounders, the physical activity condition contributed to the maintenance of academic performance, whereas a decrease was observed in learners in the control condition. Furthermore, physically active and fit children tend to have better concentration performance (CP) than their less fit peers (self-reported activity; p<0.016, grip strength; p<0.009, VO2 max p>0.021).ConclusionA 20-week physical activity intervention contributes to the maintenance of academic performance among socioeconomically deprived school children in South Africa. School administrators should ensure that their school staff implements physical activity lessons, which are a compulsory component of the school by the curriculum.

BackgroundSocioeconomically deprived children are at increased risk of ill-health associated with sedentary behavior, malnutrition, and helminth infection. The resulting reduced physical fitness, growth retardation, and impaired cognitive abilities may impede children’s capacity to pay attention. The present study examines how socioeconomic status (SES), parasitic worm infections, stunting, food insecurity, and physical fitness are associated with selective attention and academic achievement in school-aged children.MethodologyThe study cohort included 835 children, aged 8–12 years, from eight primary schools in socioeconomically disadvantaged neighborhoods of Port Elizabeth, South Africa. The d2-test was utilized to assess selective attention. This is a paper and pencil letter-cancellation test consisting of randomly mixed letters d and p with one to four single and/or double quotation marks either over and/or under each letter. Children were invited to mark only the letters d that have double quotation marks. Cardiorespiratory fitness was assessed via the 20 m shuttle run test and muscle strength using the grip strength test. The Kato-Katz thick smear technique was employed to detect helminth eggs in stool samples. SES and food insecurity were determined with a pre-tested questionnaire, while end of year school results were used as an indicator of academic achievement.Principal findingsChildren infected with soil-transmitted helminths had lower selective attention, lower school grades (academic achievement scores), and lower grip strength (all p<0.05). In a multiple regression model, low selective attention was associated with soil-transmitted helminth infection (p<0.05) and low shuttle run performance (p<0.001), whereas higher academic achievement was observed in children without soil-transmitted helminth infection (p<0.001) and with higher shuttle run performance (p<0.05).Conclusions/SignificanceSoil-transmitted helminth infections and low physical fitness appear to hamper children’s capacity to pay attention and thereby impede their academic performance. Poor academic achievement will make it difficult for children to realize their full potential, perpetuating a vicious cycle of poverty and poor health.Trial registrationClinicalTrials.gov ISRCTN68411960

Background:In low-and middle-income countries, infectious diseases remain a key public health issue. Additionally, non-communicable diseases are a rapidly growing public health problem that impose a considerable burden on population health. One way to address this dual disease burden, is to incorporate (lifestyle) health promotion measures within the education sector. In the planned study, we will (i) assess and compare physical activity, physical fitness, micronutrient status, body composition, infections with soil-transmitted helminths, Schistosoma mansoni, malaria, inflammatory and cardiovascular health risk markers, cognitive function, healthrelated quality of life, and sleep in schoolchildren in Côte d'Ivoire, South Africa and Tanzania. We will (ii) determine the bi-and multivariate associations between these variables and (iii) examine the effects of a school-based health intervention that consists of physical activity, multi-micronutrient supplementation, or both. Methods: Assuming that no interaction occurs between the two interventions (physical activity and multimicronutrient supplementation), the study is designed as a cluster-randomised, placebo-controlled trial with a 2 × 2 factorial design. Data will be obtained at three time points: at baseline and at 9 months and 21 months after the baseline assessment. In each country, 1320 primary schoolchildren from grades 1-4 will be recruited. In each school, classes will be randomly assigned to one of four interventions: (i) physical activity; (ii) multi-micronutrient supplementation; (iii) physical activity plus multi-micronutrient supplementation; and (iv) no intervention, which will serve as the control. A placebo product will be given to all children who do not receive multi-micronutrient supplementation. After obtaining written informed consent from the parents/guardians, the children will be (Continued on next page)

People from low- and middle-income countries still face challenges stemming from parasitic infections. Additionally, non-communicable diseases (NCDs) and their risk factors are rapidly increasing, which puts South African children at an elevated risk of a dual disease burden, with negative consequences for child development and wellbeing. Contrastingly, regular physical activity (PA) is associated with decreased cardiovascular disease (CVD) risk. Therefore, the objective of this study was to examine whether PA is associated with the double infection-CVD phenotype burden in South African schoolchildren. 801 children (402 boys, 399 girls; mean age 9.5 years) from eight schools from disadvantaged neighbourhoods were included. Data assessment took place between February and March 2015 in Port Elizabeth, South Africa. Children who achieved PA recommendations (physically active on 6-7 days/week for at least 60 min), who were active, but below recommended standards (2-5 physically active days/week), or who were insufficiently active on almost all days (0-1 physically active days/week) were compared with regard to systolic and diastolic blood pressure, body mass index (BMI), percent body fat, and infection with soil-transmitted helminths. Moderate and high self-reported PA levels were associated with lower BMI, lower body fat, and lower risk of being hypertensive. Conversely, children with high self-reported PA were more likely to be infected with soil-transmitted helminths than peers with low PA levels. Promoting PA in disadvantaged areas is worthwhile to prevent NCD later in life, but should be combined with regular anthelminthic treatment to comprehensively improve children's health and wellbeing.

Obesity-related conditions impose a considerable and growing burden on low- and middle-income countries, including South Africa. We aimed to assess the effect of twice a 10-week multidimensional, school-based physical activity intervention on children’s health in Port Elizabeth, South Africa. A cluster-randomised controlled trial was implemented from February 2015 to May 2016 in grade 4 classes in eight disadvantaged primary schools. Interventions consisted of physical education lessons, moving-to-music classes, in-class activity breaks and school infrastructure enhancement to promote physical activity. Primary outcomes included cardiorespiratory fitness, body mass index (BMI) and skinfold thickness. Explanatory variables were socioeconomic status, self-reported physical activity, stunting, anaemia and parasite infections. Complete data were available from 746 children. A significantly lower increase in the mean BMI Z-score (estimate of difference in mean change: −0.17; 95% confidence interval (CI): −0.24 to −0.09; p < 0.001) and reduced increase in the mean skinfold thickness (difference in mean change: −1.06; 95% CI: −1.83 to −0.29; p = 0.007) was observed in intervention schools. No significant group difference occurred in the mean change of cardiorespiratory fitness (p > 0.05). These findings show that a multidimensional, school-based physical activity intervention can reduce the increase in specific cardiovascular risk factors. However, a longer and more intensive intervention might be necessary to improve cardiorespiratory fitness.