Validation of an Intermittent Shuttle Walking Protocol in Patients With COPD

Summary

In the UK, field-based walking is prescribed in the pulmonary rehabilitation (PR) setting as a convenient, less resource-intensive, and highly responsive exercise modality in COPD patients. However, endurance time during the implementation of field-based walking protocols, such as the endurance shuttle walking (ESW) protocol, is limited to only a few minutes secondary to intense exertional symptoms. It therefore seems sensible to develop an intermittent field-based walking protocol that would prolong endurance time and walking distance compared to the commonly implemented in the PR setting continuous ESW protocol. The aim of this study is three-fold: 1) to identify whether an intermittent shuttle walking protocol significantly prolongs walking distance compared to the widely implemented continuous ESW protocol in the PR setting in patients with advanced COPD; 2) to investigate the test re-test reliability of the distance walked during the intermittent shuttle walking protocol; and 3) to explore patients' and health care professionals' experiences of implementing the intermittent walking protocol and the perceived factors affecting the implementation of these protocols in the PR setting.

The study hypothesis is that the intermittent shuttle walking protocol would be associated with lower dynamic hyperinflation and breathlessness, thereby facilitating an increase in walking distance compared to the continuous ESW protocol.

The same group of patients with advanced COPD will initially perform an incremental shuttle walk test (ISWT) (visit 1) to establish peak walking speed and subsequently patients will perform the continuous ESW protocol (visit 2) at a walking speed corresponding to 85% of peak walking speed to the limit of tolerance. On two additional visits (visits 3 and 4) patients will perform two intermittent shuttle walking protocols to the limit of tolerance by alternating 1-min walking bouts at a walking speed corresponding to 85% peak walking speed (equivalent to the ESW protocol) with 1-min rest periods in between walking bouts to establish the reproducibility of this protocol. Focus group interviews with patients and healthcare professionals will be conducted to explore perceptions of undertaking and implementing, respectively the intermittent walking protocol.

Conditions

• Chronic Obstructive Pulmonary Disease

Interventions

OTHER

Incremental shuttle walking protocol (ISWT)

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.

OTHER

Endurance shuttle walking (ESW) protocol

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.

OTHER

First Intermittent shuttle walking protocol

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.

OTHER

Second Intermittent shuttle walking protocol

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.

OTHER

Focus group study

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.

Sponsors & Collaborators

• Royal Victoria Infirmary

  collaborator OTHER

• Northumbria University

  lead OTHER

Study Design

Allocation

NA

Purpose

BASIC_SCIENCE

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

40 Years

Max Age

75 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2020-10-01

Primary Completion

2022-05-31

Completion

2022-09-30