title: The combined effects of protein intake and resistance training on serum osteocalcin concentrations in strength and power athletes.
abstract: The purpose of the present investigation was to examine the combined effects of protein intake and resistance training on a blood marker of bone osteogenesis, serum osteocalcin, in Division III football players. Thirty-three resistance-trained football players (age = 20.4 +/- 1.8 years; height = 180.9 +/- 7.0 cm; body mass = 97.2 +/- 12.6 kg) were evaluated on their protein intake and subsequently underwent 10 weeks of periodized heavy resistance training during the off season. Subjects were then placed into 1 of the following 3 groups based on relative protein intake and were instructed to maintain their diets throughout the experimental period: (a) low protein intake (<1.2 g per kilogram of body mass), (b) moderate protein intake (1.21 to 1.90 g per kilogram of body mass), or (c) high protein intake (>1.91 g per kilogram of body mass). Blood sampling occurred prior to and following the 10-week resistance training period to determine resting serum osteocalcin concentrations. A significant main effect was observed following training such that only the group who consumed <1.2 g per kilogram of body mass of protein shown significant elevations in serum osteocalcin in response to resistance training (26.8 +/- 6.4 to 33.4 +/- 6.6 ng.ml(-1)). In addition, absolute protein intake was significantly correlated to serum osteocalcin concentrations (r = 0.39). The results of the present investigation demonstrated relationships between protein intake and serum osteocalcin concentrations. In addition, the osteocalcin response to short-term resistance training appeared to be affected by protein intake.
authors: Department of Health and Exercise Science, The College of New Jersey, Ewing, New Jersey 08628, USA. ratamess@tcnj.edu
authors: Nicholas A
authors: NA
authors: Ratamess
authors: Jay R
authors: JR
authors: Hoffman
authors: Avery D
authors: AD
authors: Faigenbaum
authors: Gerald T
authors: GT
authors: Mangine
authors: Michael J
authors: MJ
authors: Falvo
authors: Jie
authors: J
authors: Kang
mesh_terms: D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D015415:Biomarkers / Q000097:blood; D001823:Body Composition; D015519:Bone Density; D004044:Dietary Proteins / Q000378:metabolism*; D005538:Football / Q000502:physiology; D006801:Humans; D053580:Muscle Strength / Q000502:physiology*; D015675:Osteocalcin / Q000097:blood*; D010012:Osteogenesis / Q000502:physiology; D010806:Physical Education and Training / Q000379:methods*; D014891:Weight Lifting / Q000502:physiology*
chemical_list: D015415:Biomarkers; D004044:Dietary Proteins; D015675:Osteocalcin