Dataset Information

Chronic obstructive pulmonary disease patients increase medio-lateral stability and limit changes in antero-posterior stability to curb energy expenditure.

ABSTRACT:

Background

A relationship exists between step width and energy expenditure, yet the contribution of dynamic stability to energy expenditure is not completely understood. Chronic obstructive pulmonary disease (COPD) patients' energy expenditure is increased due to airway obstruction. Further, they have a higher prevalence of falls and balance deficits compared to controls.

Research question

Is dynamic stability different between COPD patients and controls; and is the association between dynamic stability and energy expenditure different between groups?

Methods

Seventeen COPD patients (64.3?±?7.6years) and 23 controls (59.9?±?6.6years) walked on a treadmill at three speeds: self-selected walking speed (SSWS), -20%SSWS, and +20%SSWS. Mean and variability (standard deviation) of the anterior-posterior (AP) and medio-lateral (ML) margins of stability (MOS) were compared between groups and speed conditions, while controlling for covariates. Additionally, their association to metabolic power was examined.

Results

The association between stability and power did not significantly differ between groups. However, increased metabolic power was associated with decreased MOS AP mean (p?SignificancePatients with COPD operate at the upper limit of their metabolic reserve due to an increased cost of breathing. To compensate for their lack of stability, they walked with larger margins of stability in the ML direction, instead of changing the stability margins in the AP direction, due to its association with energy expenditure.

SUBMITTER: Fallahtafti F

PROVIDER: S-EPMC6889081 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Publications

Chronic obstructive pulmonary disease patients increase medio-lateral stability and limit changes in antero-posterior stability to curb energy expenditure.

Fallahtafti Farahnaz F Curtze Carolin C Samson Kaeli K Yentes Jennifer M JM

Gait & posture 20191021

<h4>Background</h4>A relationship exists between step width and energy expenditure, yet the contribution of dynamic stability to energy expenditure is not completely understood. Chronic obstructive pulmonary disease (COPD) patients' energy expenditure is increased due to airway obstruction. Further, they have a higher prevalence of falls and balance deficits compared to controls.<h4>Research question</h4>Is dynamic stability different between COPD patients and controls; and is the association be ...[more]

PMID: 31683184

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Dataset Information

Chronic obstructive pulmonary disease patients increase medio-lateral stability and limit changes in antero-posterior stability to curb energy expenditure.

Background

Research question

Methods

Results

Publications

Chronic obstructive pulmonary disease patients increase medio-lateral stability and limit changes in antero-posterior stability to curb energy expenditure.

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