Original article
Inspiratory fraction as a marker of skeletal muscle dysfunction in patients with COPD
P. Cebolleroa, F. Zambom-Ferraresib, M. Hernándeza, J. Huetoa, J. Cascantea, M.M. Antonb,,
a Department of Pulmonary Medicine B, Complejo Hospitalario de Navarra, Spain
b Department of Health Sciences, Public University of Navarre, Spain
Received 18 April 2016, Accepted 21 July 2016

An inspiratory capacity to total lung capacity (IC/TLC) ratio of ≤25% has emerged as a better marker of mortality in chronic obstructive pulmonary disease (COPD) patients. The relationship among the IC/TLC ratio to lower extremity skeletal muscle function remains unknown.


Thirty-five men with moderate to severe COPD were divided into those with IC/TLC25% (n=16) and >25% (n=19). The subjects were tested for thigh muscle mass volume (MMT), maximal strength, power output of the lower extremities, and physical activity.


Total MMT in the IC/TLC<25% group was significantly lower (413.91±89.42cm3) (p<0.001) than in the IC/TLC>25% group (575.20±11.76cm3). In the IC/TLC25% group, maximal strength of the lower extremities and muscle peak power output of the lower extremities were 36–56% lower (p<0.01) than among the patients in the IC/TLC>25% group.


IC/TLC25% is associated with reduced maximal strength and peak power output of the lower extremities. IC/TLC25% may have an important clinical relevance as an index to determine peripheral muscle dysfunction.

Chronic obstructive pulmonary disease, Inspiratory fraction, Muscle mass, Muscle strength, Limb muscle dysfunction, Muscle power
Journal: Inspiratory fraction as a marker of skeletal muscle dysfunction in patients with COPD

This article belongs to the Journal: Pulmonology


  • Impact Factor: 1.560(2016)
  • 5-years Impact Factor: 1,100
  • SCImago Journal Rank (SJR):0,29
  • Source Normalized Impact per Paper (SNIP):0,685