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Updated: Mar 22, 2026
07:22
Measuring the Motor Aspect of Cancer-Related Fatigue using a Handheld Dynamometer
Published on: February 20, 2020
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Is rotating between static and dynamic work beneficial for our fatigue state?
Tessy Luger1, Tim Bosch2, Marco J M Hoozemans3
1Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Van der Boechorststraat 9, NL-1081 TB Amsterdam, The Netherlands; TNO, Postbus 3005, NL-2301 DA Leiden, The Netherlands; Body@Work, Research Centre of Physical Activity, Work and Health, TNO-VU/VUmc, Van der Boechorststraat 9, NL-1081 TB Amsterdam, The Netherlands.
Summary
Task rotation can reduce muscle fatigue, but self-selected rotation frequency is more effective than imposed schedules. This finding is crucial for preventing work-related musculoskeletal disorders.
Area of Science:
- Occupational health
- Ergonomics
- Musculoskeletal disorders
Background:
- Shoulder disorders are a significant component of work-related musculoskeletal disorders.
- Repetitive and monotonous tasks can lead to muscle fatigue, which may be mitigated by task rotation.
Purpose of the Study:
- To investigate the effect of rotation frequency on fatigue development during a dynamic box-lifting and static pick-and-place task.
- To compare the effectiveness of self-selected versus imposed rotation frequencies in reducing fatigue.
Main Methods:
- Ten participants performed four one-hour rotation schedules: low frequency (30 min), high frequency (6 min), and self-selected.
- Fatigue was assessed using Borg ratings, SOFI (Scale of உடலில் Fatigue and Discomfort), and electromyography (EMG) of the Trapezius and Deltoid muscles.
Main Results:
- Significant signs of fatigue were observed across most schedules, particularly in the M. Trapezius pars Descendens, as indicated by Borg and SOFI ratings.
- Task rotation frequency did not significantly affect any outcome parameters.
- The self-selected rotation schedule resulted in significantly less perceived fatigue development compared to imposed schedules.
Conclusions:
- Task rotation, especially when self-selected, shows potential in attenuating the development of work-related musculoskeletal disorders.
- Caution is advised when interpreting electromyography (EMG) indicators of fatigue in this context.
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