The study comprises 2 phases. Phase 1: Cross-sectional study investigated the duration of moderate to vigorous physical activity (MVPA) time and the total of sleep time (TST), describing and identifying factors related to duration of MVPA time and TST. Phase 2: Conduct an intervention to evaluate the effectiveness and factors related to physical activity and sleep time average day of secondary school students in Ho Chi Minh City.

Detailed of 2 phases in this study below:

Phase 1: Cross - sectional study

A cross-sectional study was conducted in 12 schools, with 2 classes selected from each school (one from grades 6-7 and one from grades 8-9). The study included a total of 948 participants with complete data for analysis (achieving the minimum sample size of 942 students). At this phase, objectives were: 1) To determine the average daily duration of MVPA and TST. 2) To investigate the association between MVPA and TST and various factors (student, family, and environmental). The sequence of activities was as follows:

1. Research team contacted the school administration to send research questionnaires and informed consent forms to students and parents of the selected classes.
2. On the survey day, researchers collected consent forms and instructed students to complete a self-management questionnaire about personal characteristics, family background, physical activity environment, and sleep habits. Afterwards, researchers guided consenting students in wearing Actigraph GT9X accelerometers, providing them with log sheets to record daily wear times.
3. After 7 consecutive days of accelerometer wear, the research team returns to the schools to collect the devices from the school health offices. Data from the accelerometers were included in the analysis only if students have worn the device for at least four days, including at least one weekend day.
4. Student physical activity and sleep data extracted using ActiLife software. The extracted parameters included: time spent in moderate-intensity physical activity (MPA), vigorous-intensity physical activity (VPA), moderate-to-vigorous physical activity (MVPA), total sleep time (TST), sleep efficiency (SE), wake after sleep onset (WASO), time in bed (TIB), and number of days with accelerometer wear.
5. Following data extraction and accelerometer recalibration, the research team continues to conduct surveys at the remaining schools as planned until the target sample size is reached.
6. Upon completion of data collection, data from all 12 schools is consolidated into a unified dataset. Response rates are calculated, and data cleaning is conducted. Subsequently, data analysis is performed to meet the objectives of Phase 1.

Phase 2: Interventional study

Students from classes of 8 schools in all 12 participating schools were selected from Phase 1. They were divided into intervention and control groups, each comprising 4 schools. The research team implemented intervention activities in the intervention group and evaluated the intervention's effectiveness after 1 and 6 months in both groups to compare changes. The objectives of Phase 2 included: 1) To compare changes in MVPA duration between the intervention and control groups before and after the intervention; 2) To compare changes in sleep quality between the intervention and control groups before and after the intervention. For the intervention group activities, the research team focused on counseling, health education, and guidance on developing plans to improve physical activity in students. The investigators implemented interventions in the following groups:

1. Students: all students from the 4 schools and students who participated in Phase 1
2. Parents
3. School administrators Besides that, 4 remaining schools in the control group continued their regular academic activities without any additional interventions related to physical activity or sleep.

The researcher assessed the changes in MVPA and sleep quality between the intervention and control groups after 1 and 6 month Actigraph using.

Inclusion criteria:

1. For school: All public secondary schools located in the district of Ho Chi Minh city.
2. For student: Students (aged 10 - 16) attending grades 6, 7, 8, and 9 in public secondary schools located in the districts of Ho Chi Minh City.

Exclusion criteria:

1. For school: All public secondary schools located in the district of Ho Chi Minh city. do not cooperate in the research.
2. For student: Students or parents of students do not agreement to participate in the study.