Affiliations: The Harold and Inge Marcus Department of Industrial
and Manufacturing Engineering, The Pennsylvania State University, University
Park, PA, USA
Note: [] Address for correspondence: Denise H. Bauer, Ph.D., School of
Engineering Design, The Pennsylvania State University, 213 Hammond Bldg,
University Park, PA 16802, USA. Tel.: +1 785 766 3034; E-mail: [email protected]
Abstract: The load of student's backpacks has raised questions over the safety
and health of schoolchildren everywhere. The purpose of this study is to use
electromyography (EMG), posture evaluation, heart rate, and ratings of
perceived exertion and perceptions of pain to find an acceptable backpack load
limit for middle school students. Twenty middle school students aged 11 to 14
(10 female and 10 male) volunteered for the study. The subjects completed two
tests, standing stationary and walking on a treadmill, where they carried 5%
incremental loads from 0% body mass (BM) to 20% BM. The study indicated
that the Borg-CR10 ratings and trunk flexion angle for the walking trial
indicated a possible load limit of 10% BM due to the non-significant
difference between 0 and 10% BM and the significant difference between 10
and 15% BM.
Keywords: Child safety, electromyography (EMG), percent body mass
