Changes in balance control during walking with exertion in adults with chronic obstructive pulmonary disease: Protocol for a pilot study

Introduction: The prevalence of accidental falls in people with Chronic Obstructive Pulmonary Disease (COPD) is higher than the general older population. Identified falls risks factors include poor balance control, increased gait variability and poor leg muscle strength from deconditioning. Exertional walking tasks form the basis of physical assessments, but changes in gait regularity during exertion has not been well researched.

Aim: This study examines changes in balance control (as measured by gait regularity and limits of stability) in adults with COPD during self-paced walking (6 Minute Walk Test) and externally paced walking with regular increases in pace (Incremental Shuttle Walking Test). Measures of exertion (Modified Borg Dyspnoea Scale, SPO2 and HR) will be recorded concurrent to each walking task. Hypothesis: It is hypothesised that as people with COPD increase their level of exertion during walking tasks their gait regularity decreases and immediately after exertional walking their balance control is worse.

Methods: Twenty people with COPD will be recruited from the University Exercise Clinic. Participants with stable COPD will perform both a 6 Minute Walk Test and an Incremental Shuttle Test one week apart in a randomised order with gait regularity and oxygen saturation recorded at one minute intervals. Both the walking tasks will be performed on a GAITRite sensor mat recording walking pattern and gait regularity. Before and after each walking task balance (Functional Reach) and perceived level of dyspnoea measures will be taken. Gait regularity will be analysed using linear regression modelling for within task and between task comparisons. A paired T test will be used to compare functional reach prior to and after each of the exertional tasks.

Discussion: This study will provide important information on safety or falls risk during common walking tasks used in the COPD population.