Accepted for Publication: August 3, 2012.
Published Online: November 5, 2012. doi:10.1001/jamaneurol.2013.646
Author Contributions:Study concept and design: Shulman, Katzel, Ivey, Sorkin, Smith, and Macko. Acquisition of data: Shulman, Katzel, Ivey, Anderson, Weiner, and Macko. Analysis and interpretation of data: Shulman, Katzel, Ivey, Sorkin, Favors, Anderson, Smith, Reich, and Macko. Drafting of the manuscript: Shulman, Katzel, Sorkin, Favors, and Macko. Critical revision of the manuscript for important intellectual content: Katzel, Ivey, Sorkin, Anderson, Smith, Reich, Weiner, and Macko. Statistical analysis: Sorkin and Favors. Obtained funding: Shulman, Katzel, and Macko. Administrative, technical, and material support: Shulman, Katzel, Ivey, Sorkin, Smith, Weiner, and Macko. Study supervision: Shulman, Katzel, and Ivey.
Conflict of Interest Disclosures: This study was funded by the Michael J. Fox Foundation for Parkinson's Research. Dr Shulman serves as Editor-in-Chief of the American Academy of Neurology's Neurology Now Patient Book Series, receives royalties from Johns Hopkins University Press, and receives research support from the National Institutes of Health (NIH; grant U01AR057967-01), the Michael J. Fox Foundation, Teva Pharmaceuticals, and the Rosalyn Newman Foundation. Dr Katzel serves as site visitor for the Association for the Accreditation of Human Research Protection Programs and receives research support from NIH grants P30 AG028747-01, K30HL04518, 1R01HL095136-01, RO1 AG034161, and RO1 DK090401-01A1, the Department of Veterans Affairs (VA), and the Michael J Fox Foundation. Dr Ivey receives government research support through VA Rehabilitation Research and Development on 2 VA Merit Awards. Dr Sorkin receives research support from the Baltimore VA Medical Center Geriatric Research Educational and Clinical Center, the Claude D. Pepper Older Americans Independence Center (grant 5T32AG000219-18), and the Michael J. Fox Foundation. Dr Anderson receives research support from the Department of VA (merit grant E7158R) and the Michael J. Fox Foundation and is a consultant for Guidepoint Global, HD Drugworks, the Huntington's Disease Society of America, Neurosearch Sweden, Lundbeck Pharmaceuticals, and the CHDI Foundation. She received speaking fees from the University of Illinois at Chicago. She served as a consultant for Bradley vs CSX, Gilmore vs Charlotte Hall, and Rosenberry vs Patel and serves as a section editor for Current Treatment Options in Neurology. Dr Smith received research support from the Michael J. Fox Foundation. Dr Reich receives research support from Chiltern and the National Institute of Neurological Disorders and Stroke and receives royalties from Informa. Dr Weiner receives research support from EMD Serono, Abbott Laboratories, and the NIH. He receives royalties from Lippincott, Elsevier, and Demos. He served on advisory boards for Santhera, Rexahn, and Shiongi Pharma. Dr Macko receives research support from the Baltimore VA Medical Center, Geriatric Research Educational and Clinical Center, the Claude D. Pepper Older Americans Independence Center, and the Michael J. Fox Foundation.
Funding/Support: This study was supported by a grant from the Michael J. Fox Foundation (to Dr Shulman). Additional resources were provided by the Baltimore VA Medical Center, Geriatric Research Education and Clinical Center, the National Institute on Aging Claude D. Pepper Older Americans Independence Center (grant P30-AG028747), and the VA Office of Rehabilitation Research and Development Center for Excellence in Exercise and Robotics for Neurological Disorders (to Dr Katzel).
Additional Contributions: We thank of Terra Hill (study coordinator); Jessica Hammers, Timothy Dehahn, Adam Swartzendruber, Kate Fiske, and William Scott (exercise physiologists); and Cherika Greene (administrative assistant) for their important contributions.