Mitochondrial Energetics in Skeletal Muscle Are Associated With Leg Power and Cardiorespiratory Fitness in the Study of Muscle, Mobility and Aging.
J Gerontol A Biol Sci Med Sci
; 78(8): 1367-1375, 2023 08 02.
Article
em En
| MEDLINE
| ID: mdl-36462195
ABSTRACT
BACKGROUND:
Mitochondrial energetics are an important property of aging muscle, as generation of energy is pivotal to the execution of muscle contraction. However, its association with functional outcomes, including leg power and cardiorespiratory fitness, is largely understudied.METHODS:
In the Study of Muscle, Mobility, and Aging, we collected vastus lateralis biopsies from older adults (n = 879, 70-94 years, 59.2% women). Maximal State 3 respiration (Max OXPHOS) was assessed in permeabilized fiber bundles by high-resolution respirometry. Capacity for maximal adenosine triphosphate production (ATPmax) was measured in vivo by 31P magnetic resonance spectroscopy. Leg extension power was measured with a Keiser press system, and VO2 peak was determined using a standardized cardiopulmonary exercise test. Gender-stratified multivariate linear regression models were adjusted for age, race, technician/site, adiposity, and physical activity with beta coefficients expressed per 1-SD increment in the independent variable.RESULTS:
Max OXPHOS was associated with leg power for both women (ß = 0.12 Watts/kg, p < .001) and men (ß = 0.11 Watts/kg, p < .050). ATPmax was associated with leg power for men (ß = 0.09 Watts/kg, p < .05) but was not significant for women (ß = 0.03 Watts/kg, p = .11). Max OXPHOS and ATPmax were associated with VO2 peak in women and men (Max OXPHOS, ßâwomen = 1.03 mL/kg/min, ßâmen = 1.32 mL/kg/min; ATPmax ßâwomen = 0.87 mL/kg/min, ßâmen = 1.50 mL/kg/min; all p < .001).CONCLUSIONS:
Higher muscle mitochondrial energetics measures were associated with both better cardiorespiratory fitness and greater leg power in older adults. Muscle mitochondrial energetics explained a greater degree of variance in VO2 peak compared to leg power.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Aptidão Cardiorrespiratória
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Limite:
Aged
/
Female
/
Humans
/
Male
Idioma:
En
Revista:
J Gerontol A Biol Sci Med Sci
Assunto da revista:
GERIATRIA
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Estados Unidos