title: Effects of 2 Years of Exercise on Gait Impairment in People With Parkinson Disease: The PRET-PD Randomized Trial.
abstract: OBJECTIVE
  This study presents a secondary analysis from the Progressive Resistance Exercise Training in Parkinson Disease (PRET-PD) trial investigating the effects of progressive resistance exercise (PRE) and a Parkinson disease (PD)-specific multimodal exercise program, modified Fitness Counts (mFC), on spatial, temporal, and stability-related gait impairments in people with PD.
  
  
  METHODS
  Forty-eight people with PD were randomized to participate in PRE or mFC 2 times a week for 24 months; 38 completed the study. Gait velocity, stride length, cadence, and double-support time were measured under 4 walking conditions (off-/on-medication, comfortable/fast speed). Ankle strength was also measured off- and on-medication. Twenty-four healthy controls provided comparison data at one time point.
  
  
  RESULTS
  At 24 months, there were no significant differences between exercise groups. Both groups improved fast gait velocity off-medication, cadence in all conditions, and plantarflexion strength off-/on-medication. Both groups with PD had more gait measures that approximated the healthy controls at 24 months than at baseline. Plantarflexion strength was significantly associated with gait velocity and stride length in people with PD at baseline and 24 months, but changes in strength were not associated with changes in gait.
  
  
  CONCLUSIONS
  Twenty-four months of PRE and mFC were associated with improved off-medication fast gait velocity and improved cadence in all conditions, which is important because temporal gait measures can be resistant to medications. Spatial and stability-related measures were resistant to long-term improvements, but did not decline over 24 months. Strength gains did not appear to transfer to gait.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A161).
authors.affiliation: Center for Education in Health Sciences (M.R.R.) and Physical Therapy and Human Movement Science (F.J.D., C.P., D.M.C.), Northwestern University, Chicago, Illinois; Physical Therapy Program, Midwestern University, Downer's Grove, Illinois (J.P.); Department of Rehabilitation Services, University of Illinois Hospital and Health Science System, Chicago (J.A.R.); Department of Kinesiology and Nutrition, University of Illinois at Chicago (L.C.G.); Department of Applied Physiology and Kinesiology, University of Florida, Gainesville (D.E.V.); Division of Geriatric Medicine, University of Colorado School of Medicine, Aurora (W.M.K.); and Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois (C.L.C.).
authors.forename: Miriam R
authors.initials: MR
authors.lastname: Rafferty
authors.forename: Janey
authors.initials: J
authors.lastname: Prodoehl
authors.forename: Julie A
authors.initials: JA
authors.lastname: Robichaud
authors.forename: Fabian J
authors.initials: FJ
authors.lastname: David
authors.forename: Cynthia
authors.initials: C
authors.lastname: Poon
authors.forename: Lisa C
authors.initials: LC
authors.lastname: Goelz
authors.forename: David E
authors.initials: DE
authors.lastname: Vaillancourt
authors.forename: Wendy M
authors.initials: WM
authors.lastname: Kohrt
authors.forename: Cynthia L
authors.initials: CL
authors.lastname: Comella
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Corcos
mesh_terms: D000368:Aged; D005081:Exercise Therapy; D020233:Gait Disorders, Neurologic / Q000628:therapy*; D006801:Humans; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications / Q000534:rehabilitation*; D011446:Prospective Studies; D055070:Resistance Training