PT - JOURNAL ARTICLE AU - Gennaro Boccia AU - Davide Dardanello AU - Nicoletta Rinaldo AU - Giuseppe Coratella AU - Federico Schena AU - Alberto Rainoldi TI - Electromyographic Manifestations of Fatigue Correlate With Pulmonary Function, 6-Minute Walk Test, and Time to Exhaustion in COPD AID - 10.4187/respcare.04138 DP - 2015 Sep 01 TA - Respiratory Care PG - 1295--1302 VI - 60 IP - 9 4099 - http://rc.rcjournal.com/content/60/9/1295.short 4100 - http://rc.rcjournal.com/content/60/9/1295.full AB - 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.