Child Health, Health Promotion, Physical Activity, Physical Fitness, Sedentary Behaviors, Sports
Conditions
Keywords
School-based intervention, Accelerometry, Physical activity, Sedentary behavior, Sports participation, Children
Brief summary
Study Rationale: Currently, a significant proportion of children in Chile do not meet recommended physical activity levels, which may adversely affect their health and development. The school environment provides an ideal setting to promote healthy habits. This study was designed to evaluate whether a school-based program incorporating physical activity, sports, and health education can improve physical fitness and increase the time children dedicate to physical activity practice. Objective: The primary objective of this study is to evaluate the impact of a two-year school-based intervention on physical activity levels, muscular fitness (measured by upper body, lower body, and abdominal muscular strength), and sports participation among Chilean schoolchildren. How the study works: This is a single-arm cluster intervention study incorporating a pre-post design. Participating schools were allocated in a specialized program focused on physical activity and the promotion of sports practice throughout two school years. What was measured: At baseline and after the two-year intervention, the following outcomes were assessed: Physical Activity Levels: Measured via accelerometry; Muscular Fitness: Assessed through muscular strength tests, including upper limb strength (handgrip strength using a dynamometer), lower limb strength (standing long jump test), and abdominal strength (60-second curl-up test). Sports Participation: Evaluated through self-reports of involvement in organized sports. Researchers compared pre- and post-intervention data between the intervention to determine if children in the special program showed significantly greater improvements compared to those in the standard routine.
Detailed description
This is a a single-arm school-based intervention study designed to address the growing concern about low levels of physical activity among schoolchildren. Currently, a significant proportion of children in Chile do not meet global physical activity recommendations, which can lead to long-term health problems. Since children spend a large part of their day at school, this environment offers a unique opportunity to promote healthier lifestyles and sustainable physical habits. The main objective of this intervention is to evaluate whether a comprehensive, two-year, multi-component program can effectively increase physical activity levels, improve physical fitness, and encourage sports participation. Unlike traditional programs that focus solely on physical education classes, this study uses a holistic approach based on three main pillars: Active Recess: Transforming school breaks into opportunities for movement through structured and supervised activities, thus reducing sedentary time during the school day. Enhanced Physical Education: Implementing high-engagement strategies within the existing curriculum to maximize benefits for students. Health Education: Involving the entire school community-including students, teachers, and families-through workshops that highlight the importance of an active life and the practice of organized sports. To ensure rigorous results, schools were randomly assigned to either an Intervention Group, which implemented the program over two school years (2024-2025). Children who did not participate in specific intervention activities continued their usual school routine and regular physical education classes; however, they were not considered a control group for analytical purposes. The program's effectiveness was evaluated through a pre-post analysis. Using high-precision tools such as ActiGraph accelerometers for objective movement tracking and standardized muscle strength tests, researchers monitored changes in children's physical health. Additionally, the study investigates the frequency of sports participation to verify whether a more active school environment leads to greater interest in organized sports. Ultimately, this study aims to provide evidence-based strategies that can be replicated in other schools in Chile and in similar contexts, contributing to the formation of a healthier and more active future generation.
Interventions
BEHAVIORALActive Schools Program
The intervention was conducted two to three times per week, depending on the specific schedule of each school. In addition to enhanced physical education classes, educational content related to the benefits of healthy behaviors was integrated across various academic subjects to increase students' awareness. During physical education classes, activities designed to maximize PA levels and improve muscular strength were implemented. Additionally, strategies to foster active recess were established, including the provision of equipment such as jump ropes, medicine balls, and resistance bands for recreational and playful activities. Specific areas were also organized for PA during breaks, featuring floor and wall markings for game and exercise stations, accompanied by instructional posters suggesting activities. These actions aimed to encourage movement and increase students' engagement in PA throughout the school day.
Children who did not participate in specific intervention activities continued their usual school routine and regular physical education classes, as mandated by the Ministry of Education of Chile; however, they were not considered a control group for analytical purposes.
Sponsors
Universidad de Santiago de Chile
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
9 Years to 11 Years
Healthy volunteers
Yes
Inclusion criteria
* Students enrolled in the third grade of elementary school at the selected schools. * Minimum enrollment period of at least one year at the current school. * Residing in the same municipality where the school is located. * Open to all students regardless of migration status.
Exclusion criteria
* Students following any type of restrictive diet related to previously diagnosed chronic diseases. * Diagnosis of chronic conditions that require dietary or physical limitations (e.g., diabetes, celiac disease, renal disease, among others).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change from Baseline in the levels of physical activity. | Baseline (Month 2-3) and End of Intervention (Month 27-30) | Average daily minutes spent at different levels of physical activity, objectively measured using ActiGraph accelerometers worn over 7 consecutive days. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change from Baseline in Upper Limb Strength | Baseline (Month 2-3) and End of Intervention (Month 27-30) | Handgrip strength (absolute strength) will be assessed using a Smedley-type handheld dynamometer, with results recorded in kilograms (kg). The participants will perform the test in a standing position with their arms extended alongside the body. Following a demonstration and a familiarization trial, two measurements will be taken for each hand, alternating between the right and left sides to allow for adequate recovery. The final score for each participant will be calculated as the mean of the two trials for each hand. |
| Change from Baseline in Sports Participation Frequency | Baseline (Month 2-3) and End of Intervention (Month 27-30) | Measured by the Physical Activity Questionnaire for Children (PAQ-C), a self-reported instrument designed to assess general levels of physical activity, with a particular focus on participation in sports and organized activities. The full title of the instrument is the Physical Activity Questionnaire for Children (PAQ-C). It consists of nine items scored on a 5-point Likert scale. The final score is the mean of these items, ranging from 1 to 5, where higher scores represent greater involvement in physical activity and sports. |
| Change from Baseline in Sedentary Behavior | Baseline (Month 2-3) and End of Intervention (Month 27-30). | Average daily minutes of sedentary behavior, measured objectively via ActiGraph accelerometry. |
| Change from Baseline in Lower Limb Strength | Baseline (Month 2-3) and End of Intervention (Month 27-30) | Evaluated using the standing long jump test, with results recorded in centimeters (cm). Participants will stand behind a starting line and perform a jump as far as possible, landing with both feet simultaneously. The distance is measured from the starting line to the heel of the foot that lands closest to the line. After a familiarization trial, two official attempts will be performed, and the final score will be recorded as the mean of the two trials. |
| Change from Baseline in Abdominal Muscle Strength | Baseline (Month 2-3) and End of Intervention (Month 27-30) | Measured using the 60-second curl-up test, recording the maximum number of correct repetitions performed within the time limit. Participants lie in a supine position with knees bent at 90 degrees and feet flat on the floor. On the signal 'Go', they perform as many controlled curl-ups as possible. The final result is recorded as the total number of successfully completed repetitions in one minute. |
Countries
Chile
Outcome results
None listed