The six-minute walk test (6MWT) is a well established field exercise test to assess the functional exercise capacity in chronic obstructive pulmonary disease (COPD). The objective of this study is to assess the impact of walking behind the patient on 6MWT distance in patients with COPD.

In a single-center, randomized crossover study, the investigators aim to elucidate whether there is a difference in the 6MWT distance when the assessor walks behind the patient compared to the patient walking alone.

Patients with COPD referred for pulmonary rehabilitation will be invited to perform an accompanied 6MWT (assessor walks behind the patient) and unaccompanied 6MWT (assessor does not walk behind the patient) in random order.

The tests will be performed at the end of a pulmonary rehabilitation program, after patients are familiarised with the 6MWT testing procedure and learning effects can be excluded.

Inclusion Criteria:

• Patients with a diagnosis of COPD according to GOLD II-IV (FEV1/FVC < 0.7, FEV1%Norm < 80%)

Exclusion Criteria:

• Inability to perform a 6MWT when arriving at the clinic (e.g., lower limb joint surgery within preceding 3 months, unstable cardiac disease, predominant neurological limitations)
• Inability to understand the instructions of the 6MWT, either of language or cognitive reasons