Skeletal muscle contractile and noncontractile components in young and older women and men. J Appl Physiol (1985) 2000 Feb;88(2):662-8
Date
02/05/2000Pubmed ID
10658035DOI
10.1152/jappl.2000.88.2.662Scopus ID
2-s2.0-0033954385 (requires institutional sign-in at Scopus site) 261 CitationsAbstract
To examine the influences of age, gender, and habitual physical activity level on human skeletal muscle composition, we developed a relatively simple magnetic resonance imaging method for the quantitation of leg anterior compartment contractile and noncontractile content. We studied 23 young (11 women and 12 men, 26-44 yr old) and 21 older (10 women and 11 men, 65-83 yr old) healthy adults. Analysis was by two-factor (age, gender) ANOVA. Physical activity, quantitated by three-dimensional accelerometer worn about the waist for 1 wk, was not different between groups. Men had larger contractile and noncontractile cross-sectional areas (cm(2)) than women, with no gender effect on percent noncontractile area. Young subjects had larger contractile areas and smaller absolute (cm(2)) and relative (percent total) noncontractile areas than older subjects. There was a significant linear relationship between physical activity and percent noncontractile area in older (r = -0.68, P = 0.002) but not young subjects. These data demonstrate a more than twofold increase in the noncontractile content of locomotor muscles in older adults and provide novel support for physical activity as a modulator of this age-related change in muscle composition.
Author List
Kent-Braun JA, Ng AV, Young KAuthor
Alexander V. Ng PhD Associate Professor in the Exercise Science department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
AdultAge Factors
Aged
Aged, 80 and over
Estrogen Replacement Therapy
Exercise
Female
Humans
Magnetic Resonance Imaging
Male
Middle Aged
Muscle Contraction
Muscle, Skeletal
Postmenopause
Sex Factors
