Study design The study will employ a parallel design for 6 months including 144 patients (72 patients/group). Patients will be randomized to intervention or control group. The intervention comprises supplemental oxygen to be used during physical activity for 6 months. The control group will receive the same physical activity instructions as the intervention group during the 6 months, but they will not be able to use supplemental oxygen during physical activity.
The study will be a prospective, randomized, single-blind multi-centre intervention study with an intention to treat design (last value carry over). Inclusion will continue until 144 patients have fulfilled the 6 months. Patients will be tested at baseline and after 6 months. There will also be a follow-up after 12 months comprising questionnaires. The study will include centers in Sweden Norway, Finland, and Estonia.
