title: Tai chi practice reduces movement force variability for seniors.
abstract: BACKGROUND
  The purpose of this study was to examine whether Tai Chi practice can reduce the inconsistency of arm movement force output in older adults.
  
  
  METHODS
  Twenty seniors took part in the 8-week-long exercise intervention program (12 in Tai Chi practice, M = 79.3 years, SD = 2.4; and 8 in a locomotor activity group, walking or jogging, M = 79.5 years, SD = 1.9). Linear and curvilinear manual aiming movements were tested at the beginning (pretest), during 4th week (retest), and the end of the exercise program (post-test). The measure of vertical pressure on the surface of a tablet served as the dependent variable.
  
  
  RESULTS
  The findings suggest that the Tai Chi participants significantly reduce more pressure variability than the participants in locomotor activity group after 8 weeks of practice. Additionally, seniors produced higher pressure variability in the curvilinear task than in the linear task.
  
  
  CONCLUSIONS
  Evidence from this study proposes that Tai Chi practice may serve as a better real world exercise for reducing force variability in older adults' manual performance.
authors.affiliation: Department of Health and Human Performance, The University of Houston, Texas 77204-6321, USA. jyan@uh.edu
authors.forename: J H
authors.initials: JH
authors.lastname: Yan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001132:Arm / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007590:Jogging / Q000502:physiology; D008297:Male; D016139:Martial Arts / Q000502:physiology*; D009068:Movement / Q000502:physiology; D011312:Pressure; D011597:Psychomotor Performance / Q000502:physiology; D012815:Signal Processing, Computer-Assisted; D013314:Stress, Mechanical; D016138:Walking / Q000502:physiology