Resumo. Biophysical capabilities are inherent in human beings, among which physical strength is the prime foundationthat contributes towards the integral growth of other abilities. An important element of musclestrength in students is the development of the nervous system. In case the formation of myelin sheaths onnerve fibers is absent or incomplete, fast reactions and movements that require skill cannot be performedsuccessfully, and high levels of strength and power are impossible. This study aims to compare the prevailingdata on physical strength in students aged between 11 and 14 years old, both participating and notparticipating in extracurricular exercise programs. The study was based on descriptive and analyticalcharacteristics, observed in Treze Tílias – Santa Catarina. To determine the strength of the students thefollowing tests were taken: abdominal strength/resistance, test of explosive force in the lower limbs andalso in the upper limbs. Pearson statistical test with reliability interval of p<0,05 was used to observe ifthere is a difference between the test and retest. The result of the female evaluations showed better strengthperformance in all three tests for active girls, unlike the boys. The active boys obtained better results onlyin the horizontal jumps. The results showed that there are differences between the groups investigated andthat the active girls had better developmental/results than the inactive girls, which showed superiority inonly one of the strengths examined.