A Before-school Physical Activity Intervention Program to Improve Attention in Vulnerable Children: The Active-Start Trial
Phase: NA
Conditions: Physical Activity, Behavior, Child Behavior, Attention Deficit Hyperactivity Disorder
Sponsor: Universidad Santo Tomas

Scientific background: Despite public health concerns and the extensively documented 
health benefits of physical activity, a large proportion of Chilean children do not meet 
the physical activity recommendations (Aguilar-Farias et al., 2018). Since most children 
spend a majority of their waking hours at school, this environment is appropriate for the 
implementation of preventive interventions, particularly those that include activities 
promoting physical activity (Naylor & McKay, 2009). With the absence of 
opportunities for physical activity during the school day, before-school programs have 
become a popular option to help children increasing their physical activity levels 
(Stylianou, van der Mars, et al., 2016). Although several recent studies support a 
positive effect of before school-based physical activity on health (Westcott, Puhala, 
Colligan, Loud, & Cobbett, 2015), less literature has evaluate the cognitive outcomes 
(Stylianou, Kulinna, et al., 2016) such as attention capacity. Objective: To test the 
effectiveness of an 8-week before-school physical activity program to improve attention 
capacity, attention-deficit hyperactivity disorder and the different secondary outcomes 
among a group of socially disadvantaged Chilean children. Design: The Active-Start 
study is a non-blinded randomized controlled trial, conducted with children from three 
public schools classified as high vulnerable and located in a deprived area of Santiago 
(Chile). Methods: Preadolescents children between 8 to 10 years old,  will  be randomly  
assigned  to  a  8-weeks of  a before-school physical activity group or to a control (non-
exercise) group. Attention capacity, attention-deficit hyperactivity disorder, academic 
performance, body composition, physical fitness and social-behavioral outcomes will be 
assessed before and after the 8-week intervention. All students in fourth grade (aged 8–
10 years) within participating schools will be eligible for participation. Exclusion 
criteria included (1) children with some physical pathology or medical contraindication 

to perform physical exercise or (2) diagnosed with learning disabilities or mental 
disorders. 
 
REFERENCES 
Aguilar-Farias, N., Miranda-Marquez, S., Sadarangani, K. P., Martino-Fuentealba, P., 
Cristi-Montero, C., Carcamo-Oyarzun, J., Delgado-Floody, P., Chandia-Poblete, D., 
Mella-Garcia, C., Rodriguez-Rodriguez, F., Von Oetinger, A., Balboa-Castillo, T., 
Peña, S., Cuadrado, C., Bedregal, P., Celis-Morales, C., García-Hermoso, A., Cortinez-
& O'Ryan, A. (2018). Results from Chile’s 2018 Report Card on Physical Activity for 
Children and Youth. Journal of Physical Activity and Health, 15, 331-332.  
 
Naylor, P.-J., & McKay, H. A. (2009). Prevention in the first place: schools a setting for 
action on physical inactivity. British Journal of Sports Medicine, 43, 10-13.  
 
Stylianou, M., Kulinna, P. H., van der Mars, H., Mahar, M. T., Adams, M. A., & 
Amazeen, E. (2016). Before-school running/walking club: Effects on student on-task 
behavior. Preventive Medicine Reports, 3, 196-202.  
 
Stylianou, M., van der Mars, H., Kulinna, P. H., Adams, M. A., Mahar, M., & 
Amazeen, E. (2016). Before-school running/walking club and student physical activity 
levels: an efficacy study. Research Quarterly for Exercise and Sport, 87, 342-353.  
 
Westcott, W. L., Puhala, K., Colligan, A., Loud, R. L., & Cobbett, R. (2015). 
Physiological effects of the BOKS before-school physical activity program for 
preadolescent youth. Journal of Exercise, Sports & Orthopedics, 2, 1–7. 

 
Statistical Analysis Plan: the specific statistical methods that we hope to   apply for 
each analysis are; test of normality and homoscedasticity assumptions using Shapiro-
Wilk and Levene’s tests. Intervention effects will be estimated using mixed linear and 
logistic regression models, with adjustment for baseline outcomes, and potential 
covariates. The effect estimates for the quantitative outcome variables will be describe 
the difference between the mean change in the intervention group and the mean change 
in the control group. The effect estimates for binary outcome variables will be obtained 
from logistic regression models and will be presented as odds ratios with 95% CIs. 
Finally, regression mediation or moderation analyses will be conducted using the 
PROCESS macro 2.16 to test the mediation or moderation role of several potential 
covariates.