title: Age-related patterns in body composition for men aged 20-79 yr.
abstract: Fat-free body mass has been reported to decline by 30% between the ages of 30 and 70 yr, whereas body weight increases until age 50 yr. This study examined the age-related patterns in body composition, specifically its two components, fat-free body mass and fat mass, in 157 men aged 20-79 yr. Total body composition was assessed by hydrodensitometry and subcutaneous fat was measured with skinfolds. Approximately 15 men were tested in each of the 12 5-yr age groups (20-24, 25-29, 30-34, ... 75-79 yr). Body density, as determined by underwater weighing, was lower successively from the youngest to oldest age groups; men below age 40 yr had significantly higher (P < 0.01) body densities than the older men. Although there was a gradual decline in fat-free body mass with increasing age, there was not a significant age group effect until age 70 yr. Fat mass gradually increased with increasing age; men above age 40 yr had significantly higher (P < 0.01) total body fat when compared to the younger men. Subcutaneous body fat was similar at the distal limb locations for each age group; however, the proximal trunk locations, especially the abdomen, demonstrated significantly (P < 0.01) higher skinfold thicknesses with increasing age. In conclusion, fat-free body mass was maintained to a later age than previously reported; thus, the age-related decline in body density could be attributed to an age-related increase in body fat.
authors.affiliation: Department of Kinesiology, University of Illinois at Urbana-Champaign 61801, USA.
authors.forename: M G
authors.initials: MG
authors.lastname: Bemben
authors.forename: B H
authors.initials: BH
authors.lastname: Massey
authors.forename: D A
authors.initials: DA
authors.lastname: Bemben
authors.forename: R A
authors.initials: RA
authors.lastname: Boileau
authors.forename: J E
authors.initials: JE
authors.lastname: Misner
mesh_terms: D000273:Adipose Tissue; D000328:Adult; D000367:Age Factors; D000368:Aged; D000886:Anthropometry; D001823:Body Composition; D006801:Humans; D008297:Male; D008875:Middle Aged; D012885:Skinfold Thickness