Synergizing ergonomic principles with lean philosophy model towards productivity improvement in the shoes manufacturing industry

• Date: 17 December 2024
• Pages: 5-24
• DOI: https://doi.org/10.1108/IJWHM-10-2023-0157
• Published date: 17 December 2024
• Subject Matter: Health & social care,Healthcare management,HR & organizational behaviour,Human resource policy,Employee welfare
• Author: Shemelis Nesibu Wodajeneh,Daniel Kitaw Azene,Kassu Jilcha Sileyew

Synergizing ergonomic principles with

lean philosophy model towards

productivity improvement in the shoes

manufacturing industry

Shemelis Nesibu Wodajeneh, Daniel Kitaw Azene and

Kassu Jilcha Sileyew

Department of Mechanical Engineering, Addis Ababa Institute of Technology,

Addis Ababa University, Addis Ababa, Ethiopia

Abstract

Purpose –This study aims to address the gap in integrating ergonomic principles with lean principles in the shoe

product manufacturing process. The objective is to develop a customized model that effectively combines and

synergizes ergonomics and lean principles.

Design/methodology/approach –Primary data was collected through on-site observations, interviews and

assessment of whole-body discomfort to evaluate the implementation of lean and ergonomic principles in each

section of the shoe production process. The collected data were analysed using descriptive statistical tools,

content analysis and software such as Microsoft Excel.

Findings –The findings of the study indicate that the case company’s underperformance, achieving only

26.96% of its designed capacity and 50.19% of its planned capacity,is primarily attributed to the poor integration

of ergonomic principles with the lean philosophy model. The high prevalence of work-related musculoskeletal

disorders (WMSDs) in the shoe production process significantly contributes to a loss of productivity due to

increased absenteeism. The factory experiences a labour absenteeism rate of 5.59%, resulting in overtime and

additional costs. To address these issues, the study proposes the adoption of 8S principles and an ergo-lean

production system model. This model, conceptualized as a building construction structure, effectively

eliminates waste in the shoe production process.

Practical implications –The study’s findings will greatly enhance productivity in the shoe manufacturing

sector by establishing a work environment that prioritizes employee needs and well-being. This will have

significant practical implications for improving overall productivity in the industry.

Originality/value –This study stands out as it investigates the proactive integration of ergonomics and lean

principles in the shoe manufacturing industry,an area that has not been previously explored. By bridging the gap

between these two principles, the research contributes to the existing knowledge base.

Keywords Ergonomics, Lean principles, Shoe manufacturing industry, Productivity improvement, Workplace

Paper type Research paper

Introduction

Nowadays, achieving higher productivity is one of the crucial factors in the production field.

In addition to higher productivity, manufacturing industries must consider various other

factors such as global competition, lead-time, and meeting customer needs in terms of

quality and quantity (Mia et al., 2017). Industries striving for excellence are committed to

delivering flawless products, solutions, or services by promoting concepts like first-time-

right production and zero defects. They also focus on training and motivating staff,

integrating environmental protection into every activity, and involving staff members (Brito

International

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Workplace Health

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The authors wish to thank all the participants who generously provided their time and expertise in this

research. For feedback, we thank the staff of Industrial Engineering chairs in the School of Mechanical

and Industrial Engineering at Addis Ababa Institute of Technology.

Funding: No specific grant was obtained for this research from governmental, private, or non-profit

funding organisations.

Declaration of competing interest: The authors declare that they have no known competing financial

interests or personal relationships that could have appeared to influence the work reported in this study.

The current issue and full text archive of this journal is available on Emerald Insight at:

https://www.emerald.com/insight/1753-8351.htm

Received 28 October 2023

Revised 17 March 2024

Accepted 7 October 2024

InternationalJournal of Workplace

HealthManagement

Vol.18 No. 1, 2025

pp.5-24

©Emerald Publishing Limited

1753-8351

DOI10.1108/IJWHM-10-2023-0157

et al., 2020). To meet the demands of the current market and establish an effective and

efficient production system, many industries are modernizing their traditional management

approach and adopting lean manufacturing. Lean manufacturing, which emphasizes the

consistent elimination of waste, enhances cost, quality, productivity, and operational

performance (Peixoto et al., 2022).

However, it is important to note that lean thinking, which focuses on waste elimination,

has not always prioritized ergonomics and worker safety. Some companies that implement

lean techniques have emphasized the technical procedures of the Toyota production system

while neglecting the importance of human factors (Yang et al., 2011).Research has shown

that certain drawbacks and misunderstandings of lean principles, coupled with insufficient

lean interventions, can lead to ergonomic wastes and have a negative impact on

productivity, efficiency, safety, and health (Arezes et al., 2015;Brito et al., 2020).

Understanding the concepts of Muda, Mura, and Muri is crucial for identifying and

eliminating wastes in the production process (Alves et al., 2019). These three concepts of

Lean, known as the 3M’s, define Muda as waste, Muri as excessive or unreasonable

workloads placed on individuals or equipment beyond their capacity, and Mura as the

concept of irregularity or variability in the production process (Radin et al., 2023). In the

shoe product manufacturing industry, a lack of Muri (overload, overburden) and Mura

(irregularity, variability) can be indicators of Muda (waste) (Oliveira et al., 2018). These

issues contribute to employee absenteeism, high staff turnover, overtime work, and poor

productivity (Jan and Werner, 2019).

Toaddress these challenges and enhance industry productivity, it is important to integrate

lean and ergonomics principles at the design stages, creating a lean-ergonomic hybrid

production system. This integration ensures the safety and well-being of workers who play a

key role in implementing productivity-enhancing tools and techniques (Arezes et al., 2015;

Peixoto et al., 2022;Vinoth Kumar et al., 2021). Providing employees with comfortable and

satisfactory working conditions in a lean environment can lead to sustained improvements in

lean performance, as suggested by the social exchange theory (Yee et al., 2008). However,

previous research has shown that a lean production system often overlooks the cognitive and

physical requirements of employees, the surrounding ecosystem, and the cultural traditions

of the community in which the industry is located. Lean tools are known to be both beneficial

and complicated, and they can potentially lead to ergonomic problems (Kumar et al., 2021).

Moreover, there is a notable absence of a comprehensive model that effectively integrates

ergonomics with lean principles to establish a successful lean-ergonomics production

system.

With the objective of enhancing productivity in the shoe manufacturing industry, this study

aims to develop a model that integrates ergonomics with the principles of lean philosophy. The

focus is specifically on addressing the root causes of waste at each stage of the production

process, with the ultimate goal of eliminating them.

Methodology

In this research, a case study strategy was employed, along with multiple methods, to address

the research questions. The use of various investigation methods provided an opportunity to

qualitatively evaluate the strengths and weaknesses of different types of investigation data

when examining work-related musculoskeletal disorders (WMSDs) in the organization

(Silverstein et al., 1996). The case study approach was chosen due to its suitability in exploring

“how” or “why” questions within a real-life context, particularly when the researcher has

limited control over events (Yin, 2003).

The research aimed to answer two main research questions: (1) why was it challenging to

control and eliminate the prevalence of waste in the leather product manufacturing industry?,

and (2) How could a model be developed to integrate ergonomics with lean production

principles and reduce waste in the leather product manufacturing industry?

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