title: Hip mechanics underlie lower extremity power training-induced increase in old adults' fast gait velocity: The Potsdam Gait Study (POGS).
abstract: Aging is associated with slowed gait and old compared with young adults generally walk with greater positive hip work (H1) and reduced positive ankle work (A2). The role of exercise interventions on old adults' gait mechanics that underlie training-induced improvements in gait velocity is unclear. We examined the effects of lower extremity power training and detraining on old adults' gait kinetics.
  
  
  
  As part of the Potsdam Gait Study (POGS), healthy old adults completed a no-intervention control period (69.1±4.4yrs, n=14) or a power training program followed by detraining (72.9±5.4yrs, n=15). We measured isokinetic knee extensor and plantarflexor power and measured hip, knee and ankle kinetics at habitual, fast and standardized walking speeds.
  
  
  
  Power training significantly increased isokinetic knee extensor power (25%), plantarflexor power (43%), and fast gait velocity (5.9%). Gait mechanics underlying the improved fast gait velocity included increases in hip angular impulse (29%) and H1 work (37%) and no changes in positive knee (K2) and A2 work. Detraining further improved fast gait velocity (4.7%) with reductions in H1 (-35%), and increases in K2 (36%) and A2 (7%).
  
  
  
  Power training increased fast gait velocity in healthy old adults by increasing the reliance on hip muscle function and thus further strengthened the age-related distal-to-proximal shift in muscle function.
authors.affiliation: University of Groningen, University Medical Center Groningen, Center for Human Movement Sciences, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands. Electronic address: c.m.i.beijersbergen@umcg.nl.
authors.forename: Chantal M I
authors.initials: CMI
authors.lastname: Beijersbergen
authors.affiliation: University of Potsdam, Division of Training and Movement Sciences, Am Neuen Palais 10, D-14469 Potsdam, Germany.
authors.forename: Urs
authors.initials: U
authors.lastname: Granacher
authors.affiliation: University of Groningen, University Medical Center Groningen, Center for Human Movement Sciences, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands; University of Potsdam, Division of Training and Movement Sciences, Am Neuen Palais 10, D-14469 Potsdam, Germany.
authors.forename: Martijn
authors.initials: M
authors.lastname: Gäbler
authors.affiliation: East Carolina University, Department of Kinesiology, 332-B Ward Sports Medicine Building, Greenville, NC 27858, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: DeVita
authors.affiliation: University of Groningen, University Medical Center Groningen, Center for Human Movement Sciences, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands.
authors.forename: Tibor
authors.initials: T
authors.lastname: Hortobágyi
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology; D001696:Biomechanical Phenomena; D005081:Exercise Therapy; D005260:Female; D005684:Gait; D006615:Hip / Q000502:physiology*; D006801:Humans; D035002:Lower Extremity / Q000502:physiology*; D008297:Male; D051346:Mobility Limitation; D055070:Resistance Training; D016138:Walking
keywords: Biomechanics; Detraining; Exercise; Muscle; Walking