Open AccessFatigability of Lower Limb Muscles during Walking in Chronic Obstructive Pulmonary Disease
Author(s) -
Nicole Marquis,
Laurent J. Bouyer,
Richard Debigaré,
Louis Laviolette,
Cynthia Brouillard,
Didier Saey,
François Maltais
Publication year - 2007
Publication title -
clinical and investigative medicine
Language(s) - English
Resource type - Journals
eISSN - 1488-2353
pISSN - 0147-958X
DOI - 10.25011/cim.v30i3.1748
Subject(s) - medicine , copd , muscle fatigue , pulmonary disease , lower limb , physical medicine and rehabilitation , electromyography , tibialis anterior muscle , leg muscle , physical therapy , vastus medialis , cardiology , skeletal muscle , surgery
Background: Patients with chronic obstructive pulmonary disease (COPD) perceive much less quadriceps fatigue during walking compare to cycling. Whether other lower limb muscles could develop fatigue during walking is unknown. The purpose of this study was to assess the electrical activity of five lower limb muscles during a 6-minute walking test in 11 healthy subjects and in 10 patients with COPD matched for age and activity level.
Methods: Surface electromyographic (EMG) data were recorded in five muscle groups (soleus, gastrocnemius (GM), tibialis anterior, vastus lateralis and rectus femoris) of the right leg during the walking test. The EMG median frequency of all contractions at minute 2 and 6 were averaged for each muscle group. Ventilation, oxygen consumption and CO2 production were also continuously measured throughout the test.
Results: Although the walking distance (494 ± 116 vs. 625 ± 50 m; P < 0.01) and the walking speed (1.7 ± 0.4 vs. 2.1 ± 1.2 m·s-1; P < 0.01) were reduced in COPD compared with controls, patients worked at a higher percentage of their estimated maximum voluntary ventilation during the test (118 ± 32 % vs. 51 ± 14 %; P < 0.01). The time course of the EMG median frequency from minute 2 to 6 differed between patients with COPD and healthy controls for the soleus, GM and tibialis anterior suggesting the occurrence of a muscle fatiguing profile in COPD.
Conclusions: Evidences of a fatiguing profile was found in three lower limb muscle groups during walking in COPD despite a slower walking speed compared to healthy controls.