RESUMEN
Obesity is expected to increase in the Kingdom of Saudi Arabia (KSA). Therefore, the objective of this study was to determine the physical activity, sleep patterns and diet habits as well as the prevalence of obesity among adolescents from Ha'il City. A cross-sectional study was conducted with 1598 adolescent students (663 males and 935 females) aged 12−15 years who were randomly selected from different schools in Ha'il. Body mass index (BMI) was used to classify participants as underweight, normal weight, overweight and obese (class and class II). Moreover, physical activity, sleep patterns and diet habits were recorded. The prevalence of obesity was 52.1%. Obesity is significantly more prevalent in females compared to males (62.9% vs. 36.59%, p < 0.001). Moreover, students in the third grade are the most obese in comparison with the first and the second educational level (p < 0.001). Additionally, students aged 15 years old are the most obese compared to 12 years, 13 years and 14 years (p < 0.001). Additionally, the results showed that students who suffer from obesity eat food when they feel higher stress and tension scores and that they do not eat their meals regularly. Additionally, 79% of those who eat fried food daily are obese. It was reported that 61.1% of students in this study were physically inactive. Furthermore, 58.4% of students have a higher proportion of insufficient sleeping duration (>7 h per night) (p < 0.001). This increased rate of obesity is higher in females compared to males and it was related to inactivity as well as perturbed sleep and eating habits. Therefore, we recommend an obesity prevention program including health education in Ha'il City, KSA.