title: Skeletal Muscle and Physical Activity in Portuguese Community-Dwelling Older Adults.
abstract: The aims of this study were to describe age- and sex-related differences in total body skeletal muscle (TB-SM) mass and to determine the variance explained by physical activity (PA). This cross-sectional study included 401 males and 402 females, aged 60-79 years. TB-SM was determined by dual-energy x-ray absorptiometry (DXA) and PA by Baecke questionnaire. Statistical analysis included t test, ANOVAs, Pearson correlations, and multiple regression analysis. TB-SM mass was higher in the youngest age group when compared with the oldest in males and females. Males had greater TB-SM values than females. PA made a significant and positive contribution to the variation in TB-SM, β = 0.071; p = .016. Sex, height, fat mass, and PA explained 77% of the variance in TB-SM. The oldest cohorts and females had lower TB-SM than the younger cohorts and males. This study suggests that PA exerts a significant role in the explanation of TB-SM.
authors.forename: Élvio R
authors.initials: ÉR
authors.lastname: Gouveia
authors.forename: Bruna R
authors.initials: BR
authors.lastname: Gouveia
authors.forename: José A
authors.initials: JA
authors.lastname: Maia
authors.forename: Cameron J
authors.initials: CJ
authors.lastname: Blimkie
authors.forename: Duarte L
authors.initials: DL
authors.lastname: Freitas
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D000886:Anthropometry; D003430:Cross-Sectional Studies; D015444:Exercise / Q000502:physiology*; D005260:Female; D005684:Gait / Q000502:physiology; D006801:Humans; D057187:Independent Living; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000503:physiopathology*; D011174:Portugal; D055948:Sarcopenia / Q000503:physiopathology*; D012737:Sex Factors; D011795:Surveys and Questionnaires
keywords: lean soft tissue; lifestyle; sarcopenia