Table 1.

Inclusion criteria and exclusion criteria of the BEGYN study.

Inclusion criteria	Exclusion criteria
Female sex Age ≥ 18 years Invasive, non-metastatic breast cancer Sufficient language skills to fill the questionnaires and to write an activity diary Sufficient technical skills or support for using a smart phone and fitness tracker Given written informed consent	Any antineoplastic treatment or invasive procedures (e.g., surgery for venous port) prior to baseline measurement Life expectancy < 12 months Non-invasive disease (e.g., carcinoma in situ) Previous or current history of other neoplasia Inability to perform a spiroergometry on a tread mill Pregnant or nursing women