FN1 and chronic obstructive pulmonary disease: Exercise training induced a diverse protein expression between the two cohorts in ECMs regulating tissue structure (collagens: up-regulated only in COPD), myogenesis (SPARC: up-regulated only in healthy), necroptosis (tenascin C: up-regulated only in COPD), adherence to muscle-cell precursors (Fibronectin: up-regulated only in healthy) and tissue integrity (biglycan: down-regulated only in COPD).