Does skeletal muscle morphology or functional performance better explain variance in fast gait speed in older adults?
Aging Clin Exp Res
; 33(4): 921-931, 2021 Apr.
Article
em En
| MEDLINE
| ID: mdl-32451962
ABSTRACT
BACKGROUND:
Fast gait speed is being increasingly recognized as an important clinical tool in older adults. However, the underlying muscular and functional contributors to fast gait speed performance remain poorly understood.AIM:
We sought to determine predictors of fast gait speed in older adults. We hypothesized that lower-extremity skeletal muscle size and quality would be strong predictors.METHODS:
Ninety community-dwelling older adults (33 men, 57 women; mean ± SD age = 74 ± 6 years) participated. B-mode ultrasonography was used to capture images of the vastus lateralis, rectus femoris, and gastrocnemius in the transverse plane. Each participant performed 30-second chair stand, heel-rise, functional reach, and grip strength tests. Fast gait speed was measured using the NIH Toolbox 4-Meter Walk Test. ImageJ software was used to quantify cross-sectional area (CSA), subcutaneous tissue thickness, and echo intensity. Two separate stepwise regression analyses were performed, one using muscle morphology variables as independent variables, and another including the functional outcomes.RESULTS:
The ultrasound variables exhibited weak-to-moderate correlations with fast gait speed (|r| range = 0.168-0.416). The initial regression analysis indicated that the combination of medial gastrocnemius CSA and subcutaneous tissue thickness explained 22.8% of the variance in fast gait speed. The secondary analysis indicated that 30-second chair stand, heel-rise, and grip strength performance explained 45.5% of the variance.CONCLUSION:
While medial gastrocnemius morphology is important, measures of upper and lower-extremity muscle function are better predictors of fast gait speed. These results highlight a dissociation between skeletal muscle morphology and fast gait speed.Palavras-chave
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Força Muscular
/
Velocidade de Caminhada
Tipo de estudo:
Prognostic_studies
Limite:
Aged
/
Aged80
/
Female
/
Humans
/
Male
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article