## 4 Discussion
It is important to recognize that the duration of the intervention in this study (8 weeks) may not have been sufficient to elicit the full range of adaptations typically associated with improvements in motor qualities such as strength and endurance. While positive outcomes were observed within the available time frame, previous research suggests that longer intervention periods may be necessary to achieve more significant and lasting changes in these attributes [36]. Additionally, we may consider using more cognitive measurement tools, measuring the effect of the post-exercise intervention. The sample size and diversity are also limitations; regarding age, the sample was made up of secondary school students between 13 and 17 years old, selected from a single educational center in the city of Melilla. A randomization process was conducted at the class level to ensure the students were assigned to groups in a way that minimized selection bias. However, based on our knowledge, since late childhood and early adolescence cannot be defined by fixed chronological boundaries, childhood can be defined as the first birthday to the onset of adolescence (which requires the identification of the onset of sexual maturation) [55]. Adolescence is a difficult period to define and some suggest a range of 10-22 years in boys. The state of adolescence begins with the onset of normal puberty and ends with adult identity, roughly between 10-19 years of age [4]. However, significant interindividual variance exists for the level (magnitude of change), timing (onset of change) and tempo (rate of change) of biological maturation. The relative mismatch and wide variation in biological maturation between children of the same chronological age emphasizes the limitations in using chronological age as a determinant. Finally, causality versus correlation poses another challenge: while the study may demonstrate associations between physical activity and cognitive function, establishing causality may be difficult. This study reinforces the concept that physical fitness is closely associated with cognitive functions, specifically attention and concentration. This suggests that exercise interventions should be designed not only to improve physical health, but also to enhance cognitive performance in adolescents. By providing empirical evidence on the effects of specific exercise interventions (endurance and strength training) on both physical fitness and cognitive functions, the study supports the development of evidence-based practices in educational settings. This can inform educators and policymakers in the implementation of effective physical activity programs that address the developmental needs of adolescents. Moreover, the programs described in Tables 1 and 2 can be applied, as circuit-based organization has the potential to increase motor engagement time in physical education classes. The implications and strengths of the study are that the findings indicate that different types of exercise interventions may yield varied outcomes in terms of physical and cognitive benefits. This underscores the importance of tailoring interventions to meet the specific needs of different populations, taking into account factors such as age, fitness level and cognitive demands, and establishing different levels of execution and intensity, bringing physical activity closer to the students' concerns, including the game factors in the exercises. The implications of this research extend beyond physical education, encompassing fields such as psychology, neuroscience and public health. It encourages interdisciplinary collaboration to explore the multifaceted benefits of physical activity, promoting a comprehensive understanding of its impact on the overall well-being of students. In line with this, a significant strength of this study is its examination of both physical fitness and cognitive functions, offering a more holistic perspective of the benefits of exercise interventions.