1.Elbow-Height Handle and Staggered Stance Exhibited Greatest Force in Pushing and Pulling: A Study among Malaysian Adults
Isa Halim ; Adi Saptari ; Puvanasvaran Perumal ; Zulkeflee Abdullah ; Nurul Wirdah Mafazi ; Ahmad Faizal Salleh ; Anish Ravindra Kurup
Malaysian Journal of Medicine and Health Sciences 2022;18(No.5):104-113
Introduction: Pushing and pulling activities are common in daily life and industrial workplaces. These activities are
potentially contributing to muscle fatigue in the back and shoulder if not managed ergonomically. Therefore, this
study aimed to quantify the maximum strength of Malaysian adults in horizontal symmetrical two-handed pushing
and pulling with different handle heights and stances. Methods: Forty-seven participants of 24 males and 23 females
were recruited in pushing and pulling experiments. The participants were assistant engineers and postgraduate students of a technical university. The dependent variable was the magnitude of push/ pull force. The independent variables consisted of action, handle height and stances. The experimental design was set for 2 actions, 3 handle heights
and 2 stances, yielding 12 variables combinations. Results: Key findings of this study revealed that combination of
pull action, handle height at elbow level and staggered stance exhibited greatest force. On the contrary, combination
of push action, handle height at knuckle level and parallel stance resulted in lowest force. In pushing test, both male
and female participants obtained greatest force of 233.3 N and 121.7 N, respectively, when the handle height was
at elbow level and staggered stance. Similarly, in pulling test, males and females obtained highest force of 242.9 N
and 152.4 N, respectively. Conclusion: This study concluded that handle height at elbow level and staggered stance
exhibited greatest force in pushing and pulling activities. This study provides information to individuals who involved
in pushing and pulling tasks with least force exertion to minimize muscle fatigue in the back and shoulder. Future
studies should consider the following recommendations: 1) Participants of study should involve manufacturing industry workers. 2) To study the effect of pushing and pulling tasks on muscle activity.
2.A Review on Ergonomics Factors Determining Working in Harmony with Exoskeletons
Isa Halim ; Muhammad Nadzirul Izzat Mahadzir ; Zulkeflee Abdullah ; Muhammad Zaimi Zainal Abidin ; Mohd Nazrin Muhammad ; Adi Saptari
Malaysian Journal of Medicine and Health Sciences 2023;19(No.6):311-327
Exoskeletons are wearable devices that can enhance human strength and are used in various fields, such as healthcare and the manufacturing industry. However, poorly designed exoskeletons can strain the muscles and cause injuries to users. The objectives of this review paper are to review the ergonomics factors that contribute to a harmonious
user-exoskeleton interaction and to explore the current trends, challenges, and future directions for developing ergonomically designed exoskeletons. In this review, 102 relevant papers published from 2015 to 2023 were retrieved
from Web of Science, Scopus, and Google Scholar. These papers were considered in the analysis for gathering relevant information on the topic. The authors identified six ergonomics factors, namely kinematic compatibility, contact
pressure, postural control, metabolic cost, cognitive workload, as well as task demands and workplace conditions,
that can influence the interaction between users and exoskeletons. By understanding and addressing these ergonomics factors during the design and development process, exoskeleton designers can enhance the user experience and
adoption of the devices in daily living activities and industrial applications.