1 The Muscle Morphology, Mechanics, and Performance Laboratory, Geriatrics and Extended Care Service, Veterans Affairs Medical Center Washington, DC, USA ; Research Service, Veterans Affairs Medical Center Washington, DC, USA ; Department of Exercise Science, School of Public Health and Health Services, The George Washington University Washington, DC, USA.
2 Research Service, Veterans Affairs Medical Center Washington, DC, USA.
3 Physical Therapy, Physical Medicine and Rehabilitation Service, Veterans Affairs Medical Center Washington, DC, USA.
4 Department of Exercise Science, School of Public Health and Health Services, The George Washington University Washington, DC, USA.
5 The Muscle Morphology, Mechanics, and Performance Laboratory, Geriatrics and Extended Care Service, Veterans Affairs Medical Center Washington, DC, USA ; Department of Medicine, School of Medicine and Health Sciences, The George Washington University Washington, DC, USA.