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Updated: Aug 9, 2026

Procedures for Rat in situ Skeletal Muscle Contractile Properties
Published on: October 15, 2011
Muscle length effect on the pendulum test
V Fowler1, C G Canning, J H Carr
1School of Physiotherapy, Faculty of Health Sciences, University of Sydney, Australia.
Objective:
An investigation of the effect of the length of knee extensor muscles on the pendulum test.
Design:
Descriptive. Statistical analysis utilized analysis of variance with planned comparisons.
Setting:
Community clubs and a stroke rehabilitation unit.
Participants:
Twenty subjects aged 54 to 83 yrs, more than 6 weeks after stroke, and 31 healthy subjects aged 60 to 79 yrs.
Outcome Measures:
Two tests: pendulum test and knee extensor muscle length test.
Results:
For both affected and intact legs, stroke subjects had significantly smaller angle of reversal (p < .001), peak angular velocity (p < .001), and maximum passive knee flexion (p < .001) than healthy subjects. When angle of reversal was normalized for passive knee flexion, there were no significant differences between healthy and stroke subjects. There were no significant differences in any variable between the intact and affected legs of the stroke subjects.
Conclusion:
Soft tissue changes, rather than hyperreflexia, may explain the decreased angle of reversal and peak angular velocity in the stroke subjects studied.
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