Isokinetic leg muscle strength in older americans and its relationship to a standardized walk test: data from the national health and nutrition examination survey 1999-2000.
OBJECTIVE
To describe isokinetic knee extensor muscle strength in older U.S. men and women by age and race/ethnicity and to ascertain its relationship to a standard, timed walking-speed test.


METHODS
The U.S. National Health and Nutrition Examination Survey (NHANES) 1999-2000.


METHODS
A cross-sectional nationally representative health examination survey.


METHODS
All surveyed persons aged 50 and older (N=1,499) who performed muscle strength and timed walk examinations in the NHANES mobile examination center.


METHODS
Concentric peak torque (strength) of the knee extensors at 1.05 rads/ s(-1) velocity and a 6-m walk timed in seconds.


RESULTS
Knee extensor strength was inversely associated with age (P<.01), and women had less knee extensor muscle strength than men (P<.01). After adjustment for standing height, no significant difference in muscle strength was found across the three race/ethnicity groups (Mexican Americans, non-Hispanic blacks, and non-Hispanic whites) for men or women. After adjustment for age, race/ethnicity, weight, and height, increasing knee extensor strength was associated with significant increases in meters walked per second (P<.01).


CONCLUSIONS
Knee extensor muscle strength is affected by age and sex but not by race/ethnicity and it is significantly associated with timed walk.
Ostchega
Yechiam
Y
Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Maryland 20782, USA. yxo1@cdc.gov
Dillon
Charles F
CF
Lindle
Rosemary
R
Carroll
Margaret
M
Hurley
Ben F
BF
D001741:Black or African American; D000368:Aged; D005260:Female; D006306:Health Surveys; D006630:Hispanic or Latino; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D007866:Leg; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology*; D016138:Walking; D044465:White People