Patterns of physical activity in Portuguese adolescents. Evaluation during physical education classes through accelerometry

Objectives: The School Physical Education (SPE) is an excellent way to improve moderate and vigorous physical activity (MVPA). To improve health and fitness, the guidelines recommend that at least 50% of class time should be spent in MVPA, and few studies on this assumption have been conducted. In this way, the objective of this study was to quantifying the amount of MVPA obtained during a SPE class, according to age and gender. Methods: This study was conducted in 3 randomly selected Portuguese public schools. A random sample of 191 teenage volunteers aged between 12 to 17 years, composed by 98 males (14.51 ± 1.754 years) and 93 females (14.59 ± 1.831 years) were recruited. Accelerometer was used. Results: The mean time spent in MVPA during SPE class (MVPA/SPE) was 25.36 ± 15.69 minutes, which corresponds to 28.18% of the total time spent in SPE class. Males spend significantly more time in MVPA/SPE than females (28.95 vs. 21.58 minutes; p <0.05). As long the age increases, there is a time reduction spent in MVPA/SPE. Conclusion: The proportion of practice in MVPA during SPE class time (28.18%) fell short of the 50% recommended by guidelines to improve health. The SPE has an important role in increase daily MVPA, namely as long the age increases. Numerous possibilities exist for improving MVPA in SPE. Health-enhancing activity needs to be recognized as an important element of SPE classes.