Inclusion Criteria:  Be in the 8-16 age range To be diagnosed with cystic fibrosis according to the American Cystic Fibrosis Association consensus report criteria Having mild (FEV1 ≥ 70% predictive) lung disease according to the disease severity classification in the annual report of the American Cystic Fibrosis Society To be able to produce phlegm  Exclusion Criteria:  Contracture or deformity, History of diagnosed orthopedic problems affecting mobility or musculoskeletal surgery History of previous lung or liver transplant Have diagnosed vision, hearing, vestibular or neurological problems that may affect balance, History of hospitalization in the last 1 month Patients who have participated in any exercise training program in the last 6 months