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Updated: Apr 6, 2026

Author Spotlight: Translational Applications of Stimulated SFEMG in Rodent Models
Published on: March 8, 2024
Effect of number of motor units and muscle fibre type on surface electromyogram
Sridhar Poosapadi Arjunan1, Dinesh Kant Kumar2, Katherine Wheeler2
1School of Electrical and Computer Engineering, RMIT University, GPO Box 2476, Melbourne, VIC, Australia. sridhar.arjunan@rmit.edu.au.
Abstract:
Reduction in number of motor units (nMU) and fast fibre ratio (FFR) is associated with disease or atrophy when this is rapid. There is a need to study the effect of nMU and FFR to analyse the association with ageing and disease. This study has developed a mathematical model to investigate the relationship between nMU and FFR on surface electromyogram (sEMG) of the biceps muscles. The model has been validated by comparing the simulation outcomes with experiments comparing the sEMG of physically active younger and older cohort. The results show that there is statistically significant difference between the two groups, and the simulation studies closely model the experimental results. This model can be applied to identify the cause of muscle weakness among the elderly due to factors such as muscle dystrophy or preferential loss of type F muscle fibres.
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