Article

OBJECTIVE: To investigate the effectiveness of computing body-size-independent
hip strength measures using muscle-specific allometric scaling and ratio standard
normalization methods. DESIGN: Cross-sectional study.
SETTING: University
laboratory. PARTICIPANTS: A convenience sample of healthy participants (N=113; 42
men, 71 women). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES:
Anthropometric measurements of the leg and thigh were obtained, and maximal hip
strength was tested (medial and lateral rotation, abduction, adduction, flexion,
extension). Strength was measured isometrically as force (kg) and then converted
to torque (Nm). RESULTS: The allometric scaling analysis resulted in exponents
for normalizing body mass (BM) in each muscle group assessed. In addition, a
6-muscle average exponent was also computed (bavg) for force (men, .554; women,
.335) and torque (men, .792; women, .482). The nonsignificant results of the
linear regression analysis revealed that normalizing hip strength to BM(bavg)
(hip strength/BM(bavg)) effectively removed the influence of BM on force and
torque. However, sex should be factored into analyses of allometric scaling
because men have higher b-values than women for both force and torque. The linear
regression analyses also demonstrated that force normalized to BM (P=.162-.895)
and torque normalized to BM x Height (P=.146-.889) were body-size-independent
measures. Force normalized to BM. (P=.001-.191) and body mass index (BMI)
(P=<.001-.066), and torque normalized to BM (P=.004-.415) and BMI (P<.001) were
significantly related to BM and therefore were not body-size independent.
CONCLUSIONS: Normalizing force and torque to BM(bavg) is the most effective
method of removing body-size dependence and allowing comparisons of persons with
differing body sizes.
CI - Copyright (c) 2011 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS