Predictors of Knee Extensor Strength in Patients with Chronic Obstructive Pulmonary Disease

Skeletal muscle weakness of the lower extremities is frequently observed in chronic obstructive pulmonary disease (COPD) patients when compared to healthy age matched controls. PURPOSE: To determine predictors of knee extensor strength in COPD patients. METHODS: Knee extensor strength was measured in 21 COPD patients using an isokinetic Kin-Com dynamometer at a speed of 60° per second. Pulmonary function testing was performed using a Medical Graphics Corporation 1085D plethysmograph. Thigh muscle volume and attenuation data were obtained through computed tomography. A stepwise multivariate linear regression analysis was employed to determine whether the forced expiratory volume in one second expressed as percent of the forced vital capacity (FEV1/FVC), thigh muscle volume, and/or thigh muscle attenuation (as a measure of fat infiltration) were significant predictors of knee extensor strength. RESULTS: Thigh muscle volume and FEV1/FVC accounted for 72.3% of the variance in knee extensor strength; with thigh muscle volume accounting for 62.0% of the variance in strength and FEV1/FVC accounting for 10.3% of the variance in strength. Thigh muscle attenuation was not a significant predictor of knee extensor strength, but exhibited a trend (p=0.09) towards significance after controlling for thigh muscle volume and FEV1/FVC. CONCLUSION: Thigh muscle volume was determined to be the most significant predictor of knee extensor strength in COPD patients, with the addition of the FEV1/FVC ratio increasing the accuracy of prediction. The information acquired through this study should be used as further supporting evidence that resistance training should be included in the treatment of COPD patients.

Grantor dc:publisher

Wake Forest University

Year dc:date.issued

2010

Author dc:creator

• Garris, Jennifer L.

• Chronic Obstructive Pulmonary Disease

Handle dc:identifier.uri

http://hdl.handle.net/10339/14838

OAI identifier oai:identifier

oai:wakespace.lib.wfu.edu:10339/14838