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Related Experiment Video

Updated: May 26, 2026

Induction and Assessment of Exertional Skeletal Muscle Damage in Humans

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Published on: December 11, 2016

Isometric knee extension force measured using a handheld dynamometer with and without belt-stabilization.

Richard W Bohannon¹, Jeffrey Kindig, Gregory Sabo

¹Physical Therapy Program, Department of Kinesiology, NEAG School of Education, University of Connecticut, Storrs, CT, USA. richard.bohannon@uconn.edu

Physiotherapy Theory and Practice

|December 24, 2011

Summary

Using a belt to stabilize handheld dynamometers significantly increases measured knee extension force, overcoming tester strength limitations. This allows for higher force measurements than previously thought possible.

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Lower Limb Biomechanical Analysis of Healthy Participants

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Published on: April 15, 2020

Area of Science:

Biomechanics
Human Performance Measurement

Background:

Tester strength is a known limitation in handheld dynamometer (HHD) force measurements.
Previous studies have not quantified the maximum measurable force with and without belt stabilization.

Purpose of the Study:

To determine the maximum knee extension force measurable with an HHD, with and without belt stabilization.
To examine the relationship between tester characteristics and measured knee extension strength.

Main Methods:

20 trained testers measured isometric knee extension strength using an HHD.
Measurements were taken with and without belt stabilization.
Paired t-tests and Pearson correlations analyzed the data.

Main Results:

Belt stabilization significantly increased measured knee extension force (866.9 N vs. 470.6 N).
Tester characteristics correlated with force measurements without stabilization, but not with stabilization.
Higher forces are measurable with HHDs than previously reported.

Conclusions:

Belt stabilization overcomes tester strength limitations in HHD measurements.
This technique enables the measurement of very high knee extension forces.
Accurate force measurement is enhanced by proper stabilization techniques.