Inclusion Criteria:  Patients aged 8-18 years with a diagnosis of cystic fibrosis (CF) Access to online exercise training Percent predicted of forced expiratory volume at one second (FEV1) > 40% in pulmonary function test  Exclusion Criteria:  Being diagnosed with acute pulmonary exacerbation at the time of study and / or within the last month. Being physically or perceptually competent to exercise Patients with allergic bronchopulmonary aspergillosis (ABPA) who were treated with systemic steroid therapy Having FEV1 %< 40% at pulmonary function test.