Respiratory physiotherapy as part of a pre-operative physical training program may reduce the risk of developing post-operative complications, improving post-operative results and optimizing physical conditions in patients with a diagnosis of non-small cell lung cancer (NSCLC) undergoing lung resection surgery. During the post-operative period, performing physical exercise has also been proved to increase the capacity for exercise, improve health-related quality of life and reduce the feeling of breathlessness. Fissios App is a tool created by thoracic surgeons, physiotherapists and a specialist doctor in physical medicine and rehabilitation, which has been satisfactorily implemented in thoracic surgery patients; this contains a program of standardized respiratory physiotherapy exercises with a defined time and number of repetitions. The aim is to compare the effectiveness of use of the Fissios App tool as a complement to a peri-operative respiratory physiotherapy program compared to just attendance at a face-to-face peri-operative respiratory physiotherapy program, to reduce the incidence of post-operative complications. It is expected to include 560 patients in the study. Subsequent to evaluation by the investigator and the acceptance of participant to take part in the study, the performing of peri-operative respiratory physiotherapy is prescribed. The participants will be randomly assigned to a study group that uses the tool as a complement to the respiratory physiotherapy program or a control group that should only attend face-to-face respiratory physiotherapy sessions. All the participants should attend face-to-face respiratory physiotherapy classes taught by physiotherapists at the place and time set out in each centre before and after surgery for at least 45 minutes and at least five sessions. Moreover, study group participants may use the Fissios App tool. Investigators should fill in the pre-operative, surgery and post-operative data for each patient on the Fissios Research platform.