Study: NCT04326855

Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: Incremental shuttle walking protocol (ISWT)
Description: Patients will perform an incremental shuttle walk test to the limit of tolerance to establish peak walking speed. The test will be developed in a 10-m course corridor, and it will be externally-paced via a recorded metronome that gives a signal for each stride. The walking pace will be increased every minute and the test will be terminated when the individual is no longer able to keep up the pace. Pulmonary variables will be recorded breath-by-breath. Cardiac output will be assessed every min. Arterial oxygen saturation will be measured by a pulse oximeter. Patients will score the intensity of their breathlessness and leg discomfort using the 1-10 Borg's scale every minute.

Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: Endurance shuttle walking (ESW) protocol
Description: Subsequently, during the second visit all patients will perform the continuous endurance shuttle walk (ESW) protocol to the limit of tolerance at a walking speed corresponding to 85% of VO2 peak derived by the ISWT (visit 1). During the ESW protocol patients will receive standardized instructions to walk for as long as possible although there will be a predetermined 6 minute maximum point. No further encouragement will be provided during the exercise performance. The test will be terminated when the individual is no longer able to keep up the pace or stops due to intolerable exertional symptoms. Gas exchange and cardiorespiratory variables will be assessed as per visit 1.

Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: First Intermittent shuttle walking protocol
Description: All patients will perform an intermittent shuttle walking protocols to the limit of tolerance (visit 3) by alternating 1-min walking bouts sustained at a walking speed equivalent to 85% peak (equivalent to the continuous ESW protocol) with 1-min rest periods.The test will be terminated when the individual is no longer able to keep up the pace or stops due to intolerable exertional symptoms although there will be a predetermined 20 minute maximum point.Gas exchange and cardiorespiratory variables will be assessed as per visit 1.

Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: Second Intermittent shuttle walking protocol
Description: To obtain test re-test reliability in terms of distance walked, of cardiorespiratory and symptoms responses this intermittent shuttle walking protocol will be repeated on a different day (visit 4). The test will be terminated when the individual is no longer able to keep up the pace or stops due to intolerable exertional symptoms although there will be a predetermined 20 minute maximum point. Gas exchange and cardiorespiratory variables will be assessed as per visit 1.

Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: Focus group study
Description: Semi-structured interviews to explore patients' preferences of undertaking the intermittent or continuous ESW protocols and healthcare professionals' perceived factors affecting the implementation of these protocols in the PR setting. These semi-structured interviews consist of questions in some degree predetermined order but still ensures flexibility in the way issues are addressed to the patients. Conversation is sustained in an informal tone and lasts for about an hour. Participants are allowed for an open response in their own words.