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Date of Award


Degree Type

Thesis (On-Campus Access Only)

Degree Name

Master of Physical Therapy (MPT)

First Advisor

Lori Avedisian, MS, PT

Second Advisor

Alta Hansen, PhD, PT


The integrated electromyographic (IEMG) activity of the erector spinae (ES) muscles and the subjective comfort levels were monitored during static sitting in two types of chairs - a conventional office chair (COC) and a semi kneeling chair or back chair (BC). IMEG readings were taken at 4, 8, and 12 minute intervals at the thrid through fifth lumbar vertebrae (L3-L5) levels of the left ES of 20 healthy adults. A questionnaire to determine subjective comfort levels in regards to the neck, back and legs was given to each subject following completion of the IEMG readings. A paired t-test and Newman-Keuls post hoc analysis were used to compare IEMG levels for both chairs. Results showed a significant difference in IEMG levels for both chairs between the 4 , 8 and 12 minute intervals, and a significant difference between the two chairs at the twelve minute interval, with the BC showing lower IEMG levels than the COC . The COC was judged to be more comfortable and desirable to sit on than the BC based on subjective data obtained from the questionnaire.


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