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Updated: Aug 9, 2026
Lower Limb Biomechanical Analysis of Healthy Participants
Published on: April 15, 2020
Effects of workers' Body Mass Index and task conditions on exertion psychophysics during Vertical Handling Tasks
Ana Colim1, Pedro Arezes1, Paulo Flores2
1ALGORITMI Research Centre, School of Engineering, University of Minho, Guimarães, Portugal.
Background:
Obesity prevalence in the workforce is clearly increasing. Simultaneously, manual lifting/lowering loads, referred to as Vertical Handling Tasks (VHT) in this paper, are common in industries and services. Performing VHT exposes workers to physical overload, which can be measured using a psychophysical approach. Various risk factors can increase this overload, including individual factors such as workers' Body Mass Index (BMI).
Objective:
To study the possible effects of workers' BMI and some task conditions on physical overload during VHT.
Methods:
Psychophysical data were collected from 51 participants having different body constitutions (including non-obese, overweight and obese). The participants performed 6 VHT (3 different loads ×2 workstation configurations), during which they lifted and lowered a test-box between their knees and shoulders. For each task, they reported their perceived exertion using the Borg Category Ratio-10 (CR-10) scale.
Results:
The results showed that the CR-10 scale is sensitive to the variation of the task conditions tested. However, the psychophysical data pointed to a tendency to decrease the perception of physical overload as workers' BMI increases.
Conclusions:
This may compromise the validity of the application of psychophysical data as an ergonomic approach for Work-Related Musculoskeletal Disorders (WRMSD) prevention in obese workers.
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