title: Serum Predictors of Percent Lean Mass in Young Adults.
abstract: Lustgarten, MS, Price, LL, Phillips, EM, Kirn, DR, Mills, J, and Fielding, RA. Serum predictors of percent lean mass in young adults. J Strength Cond Res 30(8): 2194-2201, 2016-Elevated lean (skeletal muscle) mass is associated with increased muscle strength and anaerobic exercise performance, whereas low levels of lean mass are associated with insulin resistance and sarcopenia. Therefore, studies aimed at obtaining an improved understanding of mechanisms related to the quantity of lean mass are of interest. Percent lean mass (total lean mass/body weight × 100) in 77 young subjects (18-35 years) was measured with dual-energy x-ray absorptiometry. Twenty analytes and 296 metabolites were evaluated with the use of the standard chemistry screen and mass spectrometry-based metabolomic profiling, respectively. Sex-adjusted multivariable linear regression was used to determine serum analytes and metabolites significantly (p ≤ 0.05 and q ≤ 0.30) associated with the percent lean mass. Two enzymes (alkaline phosphatase and serum glutamate oxaloacetate aminotransferase) and 29 metabolites were found to be significantly associated with the percent lean mass, including metabolites related to microbial metabolism, uremia, inflammation, oxidative stress, branched-chain amino acid metabolism, insulin sensitivity, glycerolipid metabolism, and xenobiotics. Use of sex-adjusted stepwise regression to obtain a final covariate predictor model identified the combination of 5 analytes and metabolites as overall predictors of the percent lean mass (model R = 82.5%). Collectively, these data suggest that a complex interplay of various metabolic processes underlies the maintenance of lean mass in young healthy adults.
authors.affiliation: 1Nutrition, Exercise Physiology, and Sarcopenia Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts; and 2Biostatistics Research Center, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, Massachusetts.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Lustgarten
authors.forename: Lori L
authors.initials: LL
authors.lastname: Price
authors.forename: Edward M
authors.initials: EM
authors.lastname: Phillips
authors.forename: Dylan R
authors.initials: DR
authors.lastname: Kirn
authors.forename: John
authors.initials: J
authors.lastname: Mills
authors.forename: Roger A
authors.initials: RA
authors.lastname: Fielding
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood*; D001823:Body Composition / Q000502:physiology*; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D055442:Metabolome; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology; D055815:Young Adult
chemical_list: D015415:Biomarkers