Test-retest reliability of linear and nonlinear measures of postural stability during visual deprivation in healthy subjects.

[Purpose] The purpose of this study is to evaluate the reliability of linear and nonlinear measures of the center of pressure (COP) during visual deprivation. [Subjects and Methods] Fifteen young adults participated in this study. COP signals were recorded in two conditions: eyes open and eyes closed.

Reliability of SEMG measurements for trunk muscles during lifting variable loads in healthy subjects.

Objective: The reliability of surface electromyography (SEMG) derived parameters is of high importance, but there is distinct lack of studies concerning the reliability during dynamic contractions. Particularly, the similarity index reliability has not been investigated during functional task yet. The purpose of this study was to evaluate the reliability of trunk muscle activities measured by means of surface electromyography during lifting tasks over repeated trials within a day.