1. From the Physiology and Biophysics Unit (M.K., S.K., A.G., P.L., C.A., W.A.L.), University of Muenster, Germany; Mayo Foundation (M.M.R.), Rochester, Minn; Institute of Clinical Biochemistry and Pathobiochemistry (E.B.), University of Wurzburg, Germany; and Muscle Research Unit (C.G.d.R.), Bosch Institute, University of Sydney, Australia.