Effect of Active Period Length of Firefighters on Respiratory and Climbing

The goal of this observational cross-sectional study is to examine the effect of the active period of firefighters in the units on respiratory functions and stair climbing performance. In the relevant fire department, aged between 18 and 64, who do not have a psychological, cognitive or emotional problem, a chronic heart or lung disease that would prevent them from participating who have been active for at least two years, will be included. The main questions it aims to answer are: * What is the effect of the active period of firefighters on respiratory functions? * What is the relationship between the length of active period of firefighters in the profession and their stair climbing performance? Participants sociodemographic characteristics will be questioned by using the Demographic Data Form. * Pulmonary function test and respiratory muscle strength measurement will be performed with the Pony Fx pulmonary function test device. * The Cornell Musculoskeletal Disorders Questionnaire will be used to evaluate musculoskeletal disorders. * The 6 Minute Walk Test will be performed to evaluate exercise capacity. * Stair Climbing Test will be applied to evaluate stair climbing performance.