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Introduction: Physical activity (PA) promotion combined with multimicronutrient supplementation (MMNS) among school-age children may reduce fat mass accrual and increase muscle mass through different mechanisms and so benefit child health. This study determined the efficacy of combined interventions on body composition among South African schoolchildren and determined if micronutrients mediate these effects., Study Design: Longitudinal cluster randomized controlled trial of children followed from 2019 to 2021. Statistical analyses carried from 2022 to 2023., Setting/participants: A total of 1,304 children 6-12 years of age recruited from public schools in Gqeberha, South Africa., Intervention: Children were randomized by classes to either: (a) a physical activity group (PA); (b) a MMNS group; (c) a physical activity + multimicronutrient supplementation group (PA + MMNS); and (d) a placebo control group., Main Outcome Measures: Trajectories of overall and truncal fat free mass (FFM) and fat mass (FM) estimates in modeled at 9 and 21 months using latent growth curve models (LGCM). Changes in micronutrient concentrations at 9 months from baseline., Results: An increased FFM trajectory was found among children in the MMNS arm at 9 months (Beta 0.16, 95% CI = 0.12, 0.31). The PA and MMNS arms both had positive indirect effects on this trajectory at 9 months (Beta 0.66, 95% CI = 0.44, 0.88 and Beta 0.32 95% CI = 0.1 0.5, respectively) and similarly at 21 months when mediated by zinc concentration changes. A reduced FM trajectory was found among children in the PA promotion arm at 9 months when using this collection point as the referent intercept. This arm was inversely associated with the FM trajectory at 9 months when mediated by zinc changes., Conclusions: PA and MMNS promotion in school-based interventions directly contributed to reductions in FM and increased FFM among South African children and indirectly through changes in micronutrient status., Trial Registration: ISRCTN, ISRCTN29534081. Registered on August 9, 2018 Institutional review board: Ethikkommission Nordwest- und Zentralschweiz" (EKNZ, project number: Req-2018-00608). Date of approval: 2018., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Childhood hypertension drives hypertension in later life; hence, assessing blood pressure in children is an important measure to determine current and future cardiovascular health. There is, however, a paucity of childhood blood pressure data, particularly for sub-Saharan Africa. This study explores blood pressure and associations with age, sex, socioeconomic status, physical activity, fitness, and cardiovascular risk markers. In the 'Disease, Activity and Schoolchildren's Health' (DASH) study, a cross-sectional analysis was conducted in disadvantaged neighbourhoods in the Eastern Cape province of South Africa. Assessments included blood pressure, accelerometer-measured physical activity, physical fitness, and cardiovascular risk markers. The study consisted of 785 children (383 boys, 402 girls, M = 12.4±0.9 years). Overall, 18% of the children were classified as hypertensive, while 20% were either overweight/obese, and almost four out of ten children did not meet global daily physical activity recommendations. Hypertensive children were more likely to be overweight/obese, χ 2 (2,785) = 14.42, p < 0.01, but only if they did not meet physical activity recommendations, χ 2 (2,295) = 11.93, p < 0.01. Considering the moderating effect which sufficient activity has on the relationship between hypertension and body weight, more emphasis should be placed on early primary health intervention and education strategies.

Introduction: Regular physical activity is associated with multiple health benefits for children. Evidence from cross-sectional studies suggests that physical activity is positively associated with health-related quality of life (HRQoL). The promotion of physical activity, and hence HRQoL, through a school-based intervention is therefore an important endeavor, particularly in disadvantaged areas of low- and middle-income countries, including South Africa. Methods: We designed a multicomponent physical activity intervention that was implemented over a 20-week period in 2015 in eight disadvantaged primary schools of Port Elizabeth, South Africa. Overall, 758 children aged 8-13 years participated. HRQoL was measured with the 27-item KIDSCREEN questionnaire. Self-reported physical activity was assessed with a single item of the Health-Behavior of School-Aged Children test, and cardiorespiratory fitness with the 20-m shuttle run test. Post-intervention scores were predicted with mixed linear regression models, taking into consideration the clustered nature of the data. Results: Higher baseline levels as well as increasing levels of self-reported physical activity predicted all dimensions of children's HRQoL. Baseline levels and increases in cardiorespiratory fitness predicted children's self-perceived physical well-being (one of the HRQoL subscales). Participation in the multicomponent physical activity intervention did not affect children's HRQoL. Conclusion: Higher and increasing self-reported physical activity predict all assessed HRQoL dimensions, which underlines that the promotion of regular physical activity among children living in disadvantaged settings is an important public health measure. Policy makers should encourage schools to create physical activity friendly environments, while schools should implement regular physical education as proposed by the school curriculum., (Copyright © 2020 Gall, Walter, du Randt, Adams, Joubert, Müller, Nqweniso, Pühse, Seelig, Smith, Steinmann, Utzinger and Gerber.)

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.

Objectives: To 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., Design: Cluster randomized control trial., Methods: The 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)., Results: Our 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)., Conclusion: A 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., Competing Interests: The authors have declared that no competing interests exist.

The study investigated whether typical psychological, physiological, and neurophysiological changes from a single exercise are affected by one's beliefs and expectations. Seventy-six participants were randomly assigned to four groups and saw different multimedia presentations suggesting that the subsequent exercise (moderate 30 min cycling) would result in more or less health benefits (induced expectations). Additionally, we assessed habitual expectations reflecting previous experience and beliefs regarding exercise benefits. Participants with more positive habitual expectations consistently demonstrated both greater psychological benefits (more enjoyment, mood increase, and anxiety reduction) and greater increase of alpha-2 power, assessed with electroencephalography. Manipulating participants' expectations also resulted in largely greater increases of alpha-2 power, but not in more psychological exercise benefits. On the physiological level, participants decreased their blood pressure after exercising, but this was independent of their expectations. These results indicate that habitual expectations in particular affect exercise-induced psychological and neurophysiological changes in a self-fulfilling manner.

Objective: The present research introduces an extended conceptualisation of self-concordance, which is considered an attribute not only of goals, but also of goal intentions. Based on a corresponding operationalisation, we investigate the interplay of both intention strength and intention self-concordance in the prediction of physical activity., Design: Data were taken from a longitudinal study of 134 obese people who were asked to fill out a questionnaire three times every six months., Main Measures: Physical activity and intention self-concordance were measured by validated scales. Intentions strength was assessed by an item typically employed in the extant literature., Results: Logistic regression analyses and path analyses showed both intention strength and self-concordance to be significant predictors of changes in physical activity over time. Additional analyses found self-efficacy to be a significant predictor of intention strength and self-concordance; for outcome expectations this was not the case., Conclusions: Findings support the idea that intention strength and self-concordance are two critical facets of a goal intention that need to be considered in the prediction of physical activity participation. Whereas intention strength refers to the degree of determination with which a goal intention is adopted, self-concordance rather captures the quality of this intention.

Objective: The study aimed at uncovering the correlates of reduced exercise in depressive patients. On the basis of the Health Action Process Approach (Schwarzer, 2011 ), we hypothesised that reduced exercise in depressive patients can be explained by motivational deficits and volitional deficits., Design: A longitudinal sample of 56 clinically depressive outpatients was compared to a sample of 56 parallelised non-depressive controls., Main Outcome Measures: Self-reported intention, exercise, and motivational and volitional HAPA variables were measured with self-report questionnaires at baseline and four-week follow-up., Results: Depressive patients showed a motivational deficit: they had significantly reduced intentions to exercise compared to non-depressive participants, and they suffered from reduced self-efficacy and increased negative outcome expectations. No differences were found with regard to positive outcome expectations. Depressive patients also showed a volitional deficit: depressive high-intenders were less capable of transforming their intention into action than non-depressive high-intenders. They produced less action plans, had less maintenance self-efficacy and were more easily distracted by barriers., Conclusion: The lower level of exercise among depressive patients is partly due to motivational, partly to volitional deficits. Interventions should be stage-matched and should focus on pessimistic beliefs (negative outcome expectations, self-efficacy) and planning deficits in depression.

Objective: To investigate how the effects of a group-based intervention program (MoVo-LISA) on exercise behaviour were mediated by cognitive variables. Different causal models mapping the short-term (adoption) and long-term (maintenance) intervention effects were tested using path analyses., Design: N = 220 in-patients of a rehabilitation clinic were assigned to an usual care or intervention group (quasi-experimental design). Questionnaire-based assessment was conducted at baseline; discharge; and at six weeks, six months and 12 months post discharge., Measures: The potential mediator variables were outcome expectations, self-efficacy, strength of goal intention (intention strength), self-concordance, action planning and barrier management., Results: Observed intervention effects on exercise behaviour (p < 0.05) were mediated by intention strength at the adoption and maintenance stages, by action planning only at the adoption, and by barrier management only at the maintenance stage. Self-efficacy and outcome expectations were only indirectly involved in these mediations by affecting intention strength and self-concordance., Conclusion: This is the first study to track the cognitive mediation processes of intervention effects on exercise behaviour over a long time-period by differentiating the adoption and maintenance stages of behaviour change. The findings emphasise the importance of deconstructing intervention effects (modifiability vs. predictive power of a mediator) to develop more effective interventions.

Background: Little is known about the long-term effects of group intervention programs targeting physical exercise. This paper reports on the effectiveness of MoVo-LISA, a theory-based (MoVo-concept) standardized intervention program. Participants are taught cognitive-behavioral strategies of goal-setting, action planning, barrier management, and self-monitoring., Methods: N = 220 in-patients of an orthopedic rehabilitation clinic were assigned to the usual care group (UCG) or the intervention group (IG) (quasi-experimental design). Assessments were conducted at 5 time points., Results: At 12-month follow-up, level of exercise in the IG was 28.5 min/week higher than in the UCG (P = .05). Moreover, 50% of the IG was exercising for at least 60 min/week, but only 33% of the UCG (P = .01). During the 12 months after clinic discharge, patients of the IG reported the same low pain experience that they had reached at the end of the clinic stay, whereas UCG patients' pain experience slowly reincreased., Conclusions: Results provide evidence that intervention programs based on the MoVo concept lead to long-term improvement in exercise behavior and health status.