Exercise capacity in chronic heart failure patients is related to active gene transcription in skeletal muscle and not apoptosis.

Background: Muscle wasting partly explains exercise intolerance in chronic heart failure (CHF) patients. Skeletal muscle loss may result from apoptosis, and exercise training has been suggested to halt this process. The terminal deoxynucleotidyl transferase end-labeling (TUNEL) technique is frequently used to show apoptosis, but lacks specificity.