Introduction: Respiratory system and respiration are some of the most important physiological mechanisms of the human body. Smoking and consumption of tobacco, both through active and passive smoking, is one of the leading public health problems today, especially among young people. Anatomical characteristics of the respiratory system knowledge is a prerequisite for good reading and testing of that system. The best known and most widely used method of testing lung function is called spirometry. In a short time, the results of spirometry in a simple way give an insight look into the results of the lung function of the subjects. Subjects and methods: The study included a total of 100 respondents, juniors, cadets and pioneers of the Osijek Football Club and the Osijek Women's Football Club, as well as adolescents from the Local Communities of the City of Osijek, of the same age, who do not play sports. The first part of the study included a short questionnaire with general, demographic indicators filled out by the subjects themselves while the second part was a lung function test with a MicroLab 3300 Spirometer Mk4 spirometer. Results: The study was conducted on a sample of a total of 100 respondents girls (17%) and boys (83%), The most common age of respondents is between 17 and 18 years (63%). 24% of respondents were 16 years old, while the smallest number of respondents was 19 years old and older (13%). 51% of respondents in the observed sample are involved in sports, while 49% of respondents are not involved in sports. 39% of respondents said they are smokers, while 61% of them are non-smokers. The average height of the subjects was 177.98 centimeters, while the average absolute spirometric values were 4.30 (VC), and 4.25 (FEV1). Statistical analysis based on the results of the study found that there are no statistically significant differences in spirometric measurements between smokers and non-smokers adolescents, as well as between athletes and non-athletes, according to research objectives. Conclusion: Playing sports certainly has a positive effect on lung function, but it is also a worrying number of young people who are not physically active. Pulmonary function is a variable that can be influenced and it is unquestionable to conclude that tobacco products should be bypassed in a wide arc, and children should enroll in sports activities as much as possible. At least we should encourage youngs to engage in physical activity and stay outdoors as much as possible, to leave a healthy and physically active generation behind us.