title: Effect of whey and soy protein supplementation combined with resistance training in young adults.
abstract: The purpose was to compare changes in lean tissue mass, strength, and myofibrillar protein catabolism resulting from combining whey protein or soy protein with resistance training. Twenty-seven untrained healthy subjects (18 female, 9 male) age 18 to 35 y were randomly assigned (double blind) to supplement with whey protein (W; 1.2 g/kg body mass whey protein + 0.3 g/kg body mass sucrose power, N = 9: 6 female, 3 male), soy protein (S; 1.2 g/kg body mass soy protein + 0.3 g/kg body mass sucrose powder, N= 9: 6 female, 3 male) or placebo (P; 1.2 g/kg body mass maltodextrine + 0.3 g/kg body mass sucrose powder, N = 9: 6 female, 3 male) for 6 wk. Before and after training, measurements were taken for lean tissue mass (dual energy X-ray absorptiometry), strength (1-RM for bench press and hack squat), and an indicator of myofibrillar protein catabolism (urinary 3-methylhistidine). Results showed that protein supplementation during resistance training, independent of source, increased lean tissue mass and strength over isocaloric placebo and resistance training (P < 0.05). We conclude that young adults who supplement with protein during a structured resistance training program experience minimal beneficial effects in lean tissue mass and strength.
authors.affiliation: School of Human Kinetics, Laurentian University, Sudbury, Ontario, Canada.
authors.forename: Darren G
authors.initials: DG
authors.lastname: Candow
authors.forename: Natalie C
authors.initials: NC
authors.lastname: Burke
authors.forename: T
authors.initials: T
authors.lastname: Smith-Palmer
authors.forename: Darren G
authors.initials: DG
authors.lastname: Burke
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000652:urine; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008762:Methylhistidines / Q000652:urine*; D008894:Milk Proteins / Q000008:administration & dosage / Q000494:pharmacology*; D009124:Muscle Proteins / Q000096:biosynthesis / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000187:drug effects*; D010806:Physical Education and Training / Q000379:methods; D030262:Soybean Proteins / Q000008:administration & dosage / Q000494:pharmacology*; D019415:Torque; D014891:Weight Lifting / Q000502:physiology; D000067816:Whey Proteins
chemical_list: D015415:Biomarkers; D008762:Methylhistidines; D008894:Milk Proteins; D009124:Muscle Proteins; D030262:Soybean Proteins; D000067816:Whey Proteins; C028118:3-methylhistidine