%0 Journal Article %A Gennaro Boccia %A Davide Dardanello %A Nicoletta Rinaldo %A Giuseppe Coratella %A Federico Schena %A Alberto Rainoldi %T Electromyographic Manifestations of Fatigue Correlate With Pulmonary Function, 6-Minute Walk Test, and Time to Exhaustion in COPD %D 2015 %R 10.4187/respcare.04138 %J Respiratory Care %P 1295-1302 %V 60 %N 9 %X BACKGROUND: The aim of this study was to investigate whether electromyographic manifestations of fatigue and exercise tolerance were related to stage of disease in men with a COPD diagnosis.METHODS: Fourteen men with COPD with a diagnosis of mild to severe air flow obstruction were involved in 2 separate testing sessions. The first one consisted of a pulmonary function (FEV1 and FEV1/FVC) and an exercise tolerance assessment using the 6-min walk test. During the second session, a multichannel surface electromyography was recorded from vastus medialis and vastus lateralis muscles during an isometric knee extension at 70% of maximum voluntary contraction. The slope of muscle fiber conduction velocity during the contraction was calculated as the index of fatigue.RESULTS: Conduction velocity slope significantly correlated with FEV1 (vastus medialis: r = 0.86, P < .001; vastus lateralis: r = 0.68, P = .01), FEV1/FVC (vastus medialis: r = 0.70, P = .006), and 6-min walk test (vastus medialis: r = 0.72, P = .005; vastus lateralis: r = 0.80, P = .001).CONCLUSIONS: The electromyographic manifestations of fatigue during sustained quadriceps contraction significantly correlated with disease severity and exercise tolerance in moderate to severe COPD. %U https://rc.rcjournal.com/content/respcare/60/9/1295.full.pdf