Abstract:

Introduction:
It is usual to attribute to adolescence the physical, psychological, cognitive and sociocultural transformations that contribute to the formation of personality, and that expose adolescents to new life contexts that lead to the acquisition of behaviors, habits and lifestyle which are determinants of their health in adulthood. On the other hand, in the school environment, it is recommended that the youngsters study and achieve academic performance.

Objectives:
We aim to identify factors associated with the academic performance of adolescents, including sociodemographic, school and academic context variables, to analyze the influence that the lifestyles (physical activity, tobacco, drug and alcohol consumption, nutrition habits, leisure activities, hygiene and health promotion habits, risk and road safety behavior, sleep and rest habits) may have in the prediction of the quality of the academic performance of adolescents and to analyze the relationship these variables establish between themselves.

Participants and Methods:
A quantitative, cross-sectional, descriptive, correlational, explanatory, and retrospective study. The survey through questionnaire of direct administration and academic performance scale (Fermin, 2005) instruments were selected for the data collection. A non-probability sample of convenience consisting of 380 adolescents attending the 7th, 8th and 9th grades in the academic year 2011/2012, from a 2nd and 3rd cycle school of Viseu, Portugal, was used.

Results:
Girls, younger students, those living in rural areas, the higher socioeconomic status, those who have a parent with secondary or higher education are the ones classified as better students. They are also the adolescents with fewer years of education, those who never failed, those living closest to the school, and they spend less time traveling to school, to get the best academic performance. Also, they are the ones who collaborate on domestic activities, participate in sports / physical activity, do not smoke, do not drink, do not do drugs, do not consume stimulant drinks, have fit and healthy meals, who occupy less time per day on the computer, interactive games and tv, go out with friends moderately, usually have good quality sleep, who sleep more, that before sleep watch video, study, read, and do not use the computer, also have better school performance.

Conclusion:
The school performance was associated with sociodemographic, school and academic contextual variables, to the lifestyles and sleep habits. It is therefore concluded that the behavior of young people is crucial both for the maintenance of a healthy life as also reflected in cognitive development, concentration skills, memory, reasoning, communication, interaction, attitudes and values with direct implications on school performance and overall well-being of adolescents.

Keywords:

School performance, lifestyles, adolescence, sleep.