The Effectiveness of a Whole System Approach to Improve Physical Activity of Children Aged 5 to 11 Years Living in Multi-ethnic and Socio-economically Deprived Communities: A Controlled Before and After Trial.

IntroductionWhole system approaches to public health challenges such as low physical activity levels have the potential to create sustained behaviour change at a population level and tackle health inequalities. However, there is currently little evidence of the nature or effectiveness of adopting whole system approaches. This study evaluated whether a whole system physical activity intervention (JU:MP), was effective at improving physical activity in five- to eleven-year-olds. MethodsA before and after controlled study with two-arms (JU:MP intervention and control), was conducted in Bradford, UK with data collected at baseline and 24-months follow-up. Habitual physical activity was measured via accelerometry. The primary outcome was difference in moderate-to-vigorous intensity physical activity (MVPA) between groups at 24-months. Secondary outcomes included: sedentary time (ST), counts per minute (CPM), BMI z-score, waist circumference, social, emotional and behavioural health, and quality-of-life. An exploratory analysis compared intervention effects between sub-groups. Results1,453 children were recruited. 330 children with valid wear-time at baseline and 24- months (JU:MP group n=175, control group n =155) were included in the final analysis of physical activity outcomes. The JU:MP group improved levels of MVPA (+4.99 minutes/day, (CI = 1.01, 8.96), standardised mean difference (SMD) = 0.29), ST ( -8.69 minutes/day, CI = -16.76, -0.61), SMD = -0.20) and CPM (+32.72, CI = 5.93, 59.53, SMD = 0.28) compared to controls. There were minor differences between groups in all secondary outcomes, favouring the JU:MP group. Exploratory sub-group analysis revealed that MVPA improved for boys (+7.34 minutes/days, CI = 0.70, 13.99, SMD = 0.36) and South Asian heritage children (+7.20 minutes/day, CI = 1.67, 12.72, SMD = 0.52) in the JU:MP group compared to the control group. Conclusion: whole system approaches hold considerable promise for addressing childrens levels of physical activity at scale, whilst also tackling inequalities. Key messagesO_ST_ABSWhat is already known on this topicC_ST_ABSThe physical activity levels of children are influenced by complex political, environmental and social systems. The World Health Organisation and the International Society of Physical Activity and Health both advocate for whole system change to support population level improvements in physical activity. What the study addsThis study provides evidence that improving population levels of physical activity in children can be achieved by taking a whole system approach. How this study might affect research practice or policyThis study can give confidence to policy makers and practitioners who are considering or continuing to take a whole system approach to improve physical activity for populations at greatest need.