Article

OBJECTIVE: To assess whether adults, aged 50-59 years, who are obese or
moderately to severely obese have impaired quadriceps strength and muscle quality
in comparison with adults who are not obese, both groups with and without knee
osteoarthritis (OA). DESIGN: Cross-sectional observational study. SETTING: Rural
community acquired sample. SUBJECTS: Seventy-seven men and 84 women, aged 50-59
years. METHODS: Comparisons by using mixed models for clustered data (2 lower
limbs per participant) between groups defined by body mass index (BMI) (<30
kg/m(2), 30-35 kg/m(2), and >/=35 kg/m(2)), with and without knee OA MAIN OUTCOME
MEASUREMENT: The slope of the relationship between quadriceps muscle
cross-sectional area (CSA) and isokinetic knee extensor strength (dynamometer) in
each BMI and OA group. RESULTS: There were 113 limbs (48.7% women), 101 limbs
(38.6% women), and 89 limbs (73.0% women) in the <30 kg/m(2), 30-35 kg/m(2), and
>/=35 kg/m(2) BMI groups, respectively; knee OA was present in 10.6%, 28.7%, and
58.4% of the limbs in each of these respective groups. Quadriceps CSA did not
significantly differ among BMI groups in either gender or between subjects with
and without knee OA. Peak quadriceps strength also did not significantly differ
by BMI group or by the presence of knee OA. Multivariable analyses also
demonstrated that peak quadriceps strength did not differ by BMI group, even
after adjusting for (a) gender, (b) OA status, (c) intramuscular fat, or (d)
quadriceps attenuation. The slopes for the relationships between quadriceps
strength and CSA did not differ by BMI group, OA status, or their interaction.
CONCLUSIONS: Individuals who were obese and at risk for knee OA did not appear to
have altered muscle strength or muscle quality compared with adults who were not
obese and were aged 50-59 years. The absence of a difference in the relationship
between peak quadriceps strength and CSA provided further evidence that there was
not an impairment in quadriceps muscle quality in this cohort, which suggests
that factors other than strength might mediate the association between obesity
and knee OA.
CI - Copyright (c) 2011 American Academy of Physical Medicine and Rehabilitation.
Published by Elsevier Inc. All rights reserved.

Langue : ANGLAIS