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Updated: May 22, 2026

Measurement of Maximum Isometric Force Generated by Permeabilized Skeletal Muscle Fibers
Published on: June 16, 2015
Using submaximal contractions to predict the maximum force-generating ability of muscles
Sarah Flynn1, Brian A Knarr, Ramu Perumal
1Department of Physical Therapy, University of Delaware, Newark, Delaware 19716, USA.
Introduction:
Muscle weakness can be caused by decreases in either the maximum force-generating ability of a muscle (MFGA) or neural drive from the nervous system (e.g., after a stroke). Presently, there is no agreed-upon practical method for calculating the MFGA in individuals with central nervous system pathology. The purpose of this study was to identify the best method for determining MFGA.
Methods:
The predicted and estimated MFGA of the muscles of 23 non-neurologically impaired subjects (13 males, 21.9 ± 1.9 years) were compared using the burst superimposition, twitch interpolation, doublet interpolation, twitch-to-tetanus ratio, and the adjusted burst superimposition methods.
Results:
The adjusted burst superimposition test was the most accurate predictor of MFGA.
Conclusions:
Further testing is needed to validate the use of the adjusted burst superimposition test in a neurologically impaired population.
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