The control group did not use any of the research mobile applications, but were measured at pre, post and post 2. They continued attending physical education classes normally and practicing their sports activities.

The adolescents who used this application were required to record their weekly workouts. To do this, before starting the workout, they entered the application, selected "walking" and started the record. The application included different warnings and alerts to encourage the practice of physical activity. Each week they had to make a weekly report with the distance covered.

The adolescents who used this application were required to record their weekly workouts. To do this, before starting the workout, they entered the application, selected "walking" and started the record. The application included different warnings and alerts to encourage the practice of physical activity. Each week they had to make a weekly report with the distance covered.

The adolescents who used this application were required to record their weekly workouts. To do this, before starting the workout, they entered the application, selected "walking" and started the record. The application included different warnings and alerts to encourage the practice of physical activity. Each week they had to make a weekly report with the distance covered.

Before starting the intervention, a total of 465 adolescents participated in pretest measurements (T1).

Researchers in charge of explaining how the apps worked were not involved in the measurements or subsequent analysis, as they knew which student belonged to each App and control group. Once each app had been described and its use explained, a training plan was drawn up to be followed during the period of mandatory use.

The adolescents were motivated to utilize the app for a duration of ten weeks, aiming for a minimum usage of three times per week.

After the mandatory intervention with the mobile apps, post-test measurements were carried out (T2). Then, a period of 10 weeks was provided in which the use of the app was neither mandatory nor promoted from the physical education subject, after which the post-test 2 measurements (T3) were taken.

The Physical Activity Questionnaire for Adolescents will be used to establish the level of sports practice of the adolescents. This questionnaire includes eleven questions related to the practice of physical activity in school, after school, household chores and travel. The questionnaire makes it possible to classify adolescents as inactive or active (light, moderate or vigorous intensity).

The 20-m shuttle run test evaluates maximal aerobic capacity by means of an incremental 20-meter out-and-back test. The initial speed of the test is 8.5 km/h and is increased every minute by an audible signal. The test ends when the subject stops or fails to reach the reference line two consecutive times. The speed recorded is the speed reached in the last stage that the subject is able to complete. Through the equations of Leger et al. the reference value of the subject's VO2 max. is obtained.

The countermovement jump test (CMJ) will be used to measure this variable. This test provides information on the explosive strength of the lower body. The CMJ is a vertical jump that begins with the subject in a standing position, followed by knee flexion to a position of approximately 90 degrees, and a rapid extension of the knees to perform a jump in which the maximum height is reached. It should be noted that there is no stop in the knee flexion position since the intention is to take advantage of the explosive elastic reflex energy of the movement. The subjects will perform two repetitions of the jump 2 minutes apart. A MuscleLab force platform (Ergotest Innovation S.A., Norway) will be used to record the data, which will measure the time of flight from the time the subject takes off from the platform to the time the subject re-enters contact with the platform.