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Date of Award


Degree Type

Thesis (On-Campus Access Only)

Degree Name

Master of Physical Therapy (MPT)

First Advisor

John Medeiros, PhD, PT

Second Advisor

Jay Salzman, BS, PT


Postural stability is the ability to keep the center of body mass within a controlled base of support. Postural sway, a measurable characteristic of postural stability, is the result of continuous dynamic muscular adjustments by the body to maintain standing balance in a stable upright position. Healthy individuals can normally maintain their balance with little difficulty. it has been reported that postural sway can be decreased by physical activity. The purpose of this study was to compare postural sway of active martial arts students with postural sway of healthy active non-martial artists. Twenty subjects were chosen from two Aikido martial arts schools and compared with a group of twenty randomly recruited age and activity-matched subjects who had no martial arts training. Postural sway was measured using the AT-1 Ataxiameter System (AT-1) testing unit consisting of two footplates, a computer, color monitor, integrated software system, and an adjustable tilt platform. A two-factor balanced analysis of variance (ANOVA) was used to compare mean postural sway dispersions recorded for martial artists and the normal healthy group. No significance was found between the two groups for all eight balance tests (p=0.119). The non-martial artists demonstrated lower mean postural sway dispersion scores in all balance tests. Also there was no reduction in postural sway due to increased years of martial arts training. There were a number of limitations present in this study. For example, sample size was limited; the subjects for each group were chosen by convenience; subjects were tested with bare feet, which possibly forced them to favor uncontrolled weight shifts onto either forefoot or heel; and testing for all subjects was done at random times.


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