Effects of Lifting Method, Safety Shoe Type, and Lifting Frequency on Maximum Acceptable Weight of Lift, Physiological Responses, and Safety Shoes Discomfort Rating.

Fares F Alferdaws,Mohamed Z Ramadan

doi:10.3390/ijerph17093012

Fares F Alferdaws, Mohamed Z Ramadan

Open Access

https://doi.org/10.3390/ijerph17093012

Copy DOI

Abstract

This study aimed to investigate the physical effects of precision lifting tasks on the maximal acceptable weight of a lift (i.e., psychophysiological lifting capacity where the workers adjust the lifting weight in order to work without any fatigue or strain at the end of the work while wearing common safety shoe types). Additionally, the physical difference between the precise and non-precise lifting conditions associated with wearing safety shoes were assessed by respiration responses and shoe discomfort ratings. To achieve the objective of the study, ten healthy male workers were selected by age (between 25 to 35 years old). Their anthropometric characteristics, including knuckle height, knee height, and body mass index (BMI), were measured. A three-way repeated measures design with three independent variables was used; the variables included—the (1) lifting method (precise and non-precise), (2) lifting frequency (1 and 4 lifts per min), and (3) safety shoe type (light-duty, medium-duty, and heavy-duty). The physiological response variables and one of the subjective factors of this study were—(1) respiration responses, and (2) shoe discomfort rating, respectively. The data were analyzed using the Mauchly’s test of sphericity, Shapiro–Wilk normality test, and analysis of variance (ANOVA). The results showed that the use of heavy-duty safety shoes typically increased the shoe discomfort rating under precise lifting methods. Additionally, the lifting frequency was determined to be one of the main factors affecting respiratory responses and shoe discomfort rating. This study also found that respiration responses rose on four lifts per min as compared to 1 lift per min, regardless of the lifting method type. This study indicated that the replacement of some types of ordinary safety shoes used in some workplaces with those selected appropriately might significantly reduce the rating effort required to lift objects or tools. However, the benefits should be carefully evaluated before replacing the safety shoes.

Highlights

Manual material handling (MMH) is one of the major causes of severe industrial injury [1].MMH needs to be lifted but usually includes lifting, carrying, pushing, pulling, climbing, and rotating, all of which pose a risk of back injuries [2]
This study conducted an investigation into the effects of safety shoes on respiration response, heart rate, and safety shoes discomfort rating, under two lifting methods and lifting frequency (1 and 4 lifts/min)
The study investigated three shoe types used in different industrial settings, such as light, medium, and heavy duty safety shoes

Summary

Introduction

Manual material handling (MMH) is one of the major causes of severe industrial injury [1]. MMH needs to be lifted but usually includes lifting, carrying, pushing, pulling, climbing, and rotating, all of which pose a risk of back injuries [2]. Working conditions, such as walking and standing on a hard surface, can increase the development of musculoskeletal disorders. The shoe types that are worn and the amount of work performed can affect muscle movement, which is critical in a professional setting [3], where continuous carrying might cause muscle fatigue in the upper limbs [4]. Public Health 2020, 17, 3012; doi:10.3390/ijerph17093012 www.mdpi.com/journal/ijerph

Objectives

Methods

Results

Discussion

Conclusion