title: Taiji training improves knee extensor strength and force control in older adults.
abstract: The purpose of this study was to examine the effects of Taiji training on knee extensor strength and force control in older individuals. Twenty-six healthy older adults (71.9 +/- 1.8 years) participated in the study. Sixteen of the older adults (70.2 +/- 1.8 years) underwent Taiji training for 20 weeks (experimental group), whereas the other 10 (74.6 +/- 1.2 years) served as the control group. For both groups, strength and force control of the knee extensors was assessed twice with an isokinetic dynamometer. Strength was assessed with a maximum voluntary isometric contraction (MVC). Force control was measured as the standard deviation (SD) and coefficient of variation (CV) of force during a constant isometric knee extension task at 2%, 30%, 60%, and 90% MVC. For the experimental group, MVC significantly increased (19.5 +/- 4.9%) and the CV of force decreased (18.9 +/- 3.3%) following Taiji training. Improvements in the CV of force were primarily due to decreases in the SD of force (R(2) =.86) rather than increases in strength (R(2) =.12). Furthermore, decreases in SD of force were independent of improvements in strength. For the control group, strength, SD, and CV of force were not different for the 2 tests. The overall findings suggest that Taiji training improves knee extensor strength and force control in older adults.
authors.affiliation: University of Illinois at Urbana-Champaign, USA. evangelos.christou@colorado.edu
authors.forename: Evangelos A
authors.initials: EA
authors.lastname: Christou
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.forename: Karl S
authors.initials: KS
authors.lastname: Rosengren
mesh_terms: D000368:Aged / Q000502:physiology*; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D007717:Knee / Q000502:physiology*; D008297:Male; D009132:Muscles / Q000502:physiology; D026302:Tai Ji