Effects of strap support in a hand-held device on the muscular activity in female workers assessed by electromyography and subjective rating

Abstract

The present study evaluates the potential mitigation of physical workload when using strap support for a portable device. The experiments were designed as consecutive sessions over a 2-h period. Electromyogram signals were recorded from four muscles of six subjects. The perceived level of fatigue on the whole body as well as in the shoulder, arm, lower back and legs was assessed using Borg's CR-10 scale. All subjects were tested under eight experimental conditions. Results indicated that the biceps brachii muscle displayed significantly lower activity with strap support than without a strap. In the experiments with and without a strap, different levels of force were imposed on the various muscles, which caused changes in the distribution of the physical load. Although the role of the strap might seem evident, using strap support did not always decrease the sensation of fatigue. However, for short-term tasks, using a strap may be recommended.

Ergonomic design and evaluation of new surgical scissors

“…In addition to subjective assessment, electromyography (EMG) is often used as an objective index of physiological fatigue (Berguer 1998;Matern and Waller 1999;Bisht and Khan 2013). As EMG directly expresses the performance level of muscular activity (Hoozemans and van Dieën 2005), it is the most useful method for tool evaluation and redesign (Lintula and Nevala 2006;Koleini Mamaghani et al 2009;Suzuki et al 2013). We therefore set out in this study to ergonomically redesign the handle of Metzenbaum scissors and determine the effectiveness compared to traditional surgical scissors using various usability indices.…”

Neural network-based comfort evaluation method for handheld sports products

“…The questionnaire takes into account the functionality, physical irritation, tactile characteristics, and quality and appearance of the hand tools [8][9][10] . Discomfort perception has also been found to be a potential factor influencing the comfort experience, generally using the validated Local perceived discomfort of arm and hand (LPD) map [11][12][13][14] to be assessed.…”

Dynamic Electromyography Analysis of Shoulder Muscles for One-handed Manual Material Handling

“…As a result, it was analyzed muscle activity increased linearly, as motion continued. In a research of Koleini Mamaghani et al (2009) considering one-handed motion, it was analyzed that significant differences of muscle activity (iEMG) occurred, according to working conditions. Diederichsen et al (2007) analyzed each muscle's activity, according to shoulder joint's abduction and rotation motions.…”