The durability of membrane electrode assemblies (MEAs) with varying amounts of Pt loading on the cathode of polymer electrolyte membrane fuel cells was investigated using load cycling as an accelerated degradation test (ADT). The single-cell performance of the MEA as determined by the ADT declined by approximately 34, 48, and 78%, when cathode Pt loading in the MEA was reduced to 0.3, 0.2, and 0.1 mg cm(-2), respectively. The increase in MEA performance declined at higher cathode Pt loading conditions, and the degradation rate of MEA performance was also diminished. To characterize the electrochemical and structural properties of the MEAs, cyclic voltammograms, electrochemical impedance spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and field-emission scanning electron microscopy were utilized before and after ADT. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.