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Updated: Jun 19, 2026

In vivo Measurement of Knee Extensor Muscle Function in Mice
Published on: March 4, 2021
Knee extension strength and adiposity explain some of older adults' self-reported difficulty with mobility
1Department of Physical Therapy, Neag School of Education, University of Connecticut, Storrs, CT 06269-2101, USA. richard.bohannon@uconn.edu
Background And Purpose:
As adults lose strength with age and an increasing proportion of older adults are overweight or obese, this study was undertaken to examine the contribution of strength and adiposity to mobility difficulties among community-dwelling men and women at least 65 years of age.
Methods:
The National Health and Nutrition Examination Survey (NHANES) 2001-2002 provided complete demographic, anthropometric, strength, and self-reported mobility data for 687 men and women.
Results:
Spearman correlations of adiposity (.024-.149) and knee extension strength (-.120-.234) with mobility difficulty were mostly significant but not strong. Multiple regression showed that together, body mass index, knee extension force, and age offered the best explanation of mobility difficulty.
Conclusions:
Adiposity and strength have relevance to the self-reported mobility difficulty of older adults. However, they leave most of such difficulty unexplained.
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