1. Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT 84148, U.S.A.
2. Department of Internal Medicine, University of Utah, Salt Lake City, UT 84132, U.S.A.
3. Geriatric Research, Education, and Clinical Center, VAMC, Salt Lake City, UT 84148, U.S.A.
4. Cleveland VA Medical Center, Cleveland, OH 44106, U.S.A.
5. Department of Neurology, University of Utah, Salt Lake City, UT 84132, U.S.A.
6. Department of Anesthesiology, University of Utah, Salt Lake City, UT 84132, U.S.A.
7. Department of Cardiology and Copenhagen Muscle Research Center, Copenhagen National Hospital, Copenhagen, Denmark
8. †University of Utah Center on Aging, Salt Lake City, UT 84132, U.S.A.