Background: Physical activity (PA) plays a vital role in both physical and mental development of adolescents. This study aims to determine adolescent physical activity status and several related factors and to preliminarily evaluate its effect on the development of adolescent height and weight.

Materials and Methods: This analytical cross-sectional study involved 932 students, chosen by the multi-stage sampling method. The data were collected by a structured questionnaire referenced from GSHS and YRBS questionnaires and the measurement of height and weight.

Results: Physical inactivity among adolescents accounted for 71.1% (95% CI: 68.1 - 74.0), in which female adolescents is higher than male adolescents (77.4% vs 60.6%). For every one-day increase of meeting the PA recommendation, there is a growth in adolescent height and weight corresponding to 0.41 (cm) (95% CI: 0.14-0.68) and 0.37 (kg) (95% CI: 0.14- 0.61), respectively. Gender and received the parent concerns were two factors which are most effective to physical inactivity in adolescents.

Conclusions: Lack of PA still being an alarming concern, especially among adolescent girls. Physical inactivity could affect the development of height and weight during adolescence. Taking more robust measures must be needed to improve PA for adolescents.