Patients with idiopathic pulmonary fibrosis (IPF) experience a poor quality of life and reduced physical activity due to severe breathlessness and the associated pathophysiological consequences. The aim of our study was to investigate fitness indicators, quality of life, anxiety and depression in IPF patients during a four-week training and detraining period. A total of 13 IPF patients participated in the study. Measurements included anthropometric characteristics and cardio-pulmonary-metabolic-hemodynamic parameters before and after a six-minute walking test, as well as a quality of life, anxiety and depression questionnaire at three time points. Physical fitness status was significantly associated with quality of life, anxiety, depression, and cardio-pulmonary-metabolic-hemodynamic parameters and six-minute walking test-derived indices. In conclusion, our study has revealed bidirectional interrelationships between health status and training/detraining. It demonstrates that even brief remote training sessions can improve fatigue and functional status.