title: Effect of carbohydrate feeding on the bone metabolic response to running.
abstract: Bone resorption is increased after running, with no change in bone formation. Feeding during exercise might attenuate this increase, preventing associated problems for bone. This study investigated the immediate and short-term bone metabolic responses to carbohydrate (CHO) feeding during treadmill running. Ten men completed two 7-day trials, once being fed CHO (8% glucose immediately before, every 20 min during, and immediately after exercise at a rate of 0.7 g CHO · kg body mass(-1) · h(-1)) and once being fed placebo (PBO). On day 4 of each trial, participants completed a 120-min treadmill run at 70% of maximal oxygen consumption (V̇o2 max). Blood was taken at baseline (BASE), immediately after exercise (EE), after 60 (R1) and 120 (R2) min of recovery, and on three follow-up days (FU1-FU3). Markers of bone resorption [COOH-terminal telopeptide region of collagen type 1 (β-CTX)] and formation [NH2-terminal propeptides of procollagen type 1 (P1NP)] were measured, along with osteocalcin (OC), parathyroid hormone (PTH), albumin-adjusted calcium (ACa), phosphate, glucagon-like peptide-2 (GLP-2), interleukin-6 (IL-6), insulin, cortisol, leptin, and osteoprotogerin (OPG). Area under the curve was calculated in terms of the immediate (BASE, EE, R1, and R2) and short-term (BASE, FU1, FU2, and FU3) responses to exercise. β-CTX, P1NP, and IL-6 responses to exercise were significantly lower in the immediate postexercise period with CHO feeding compared with PBO (β-CTX: P = 0.028; P1NP: P = 0.021; IL-6: P = 0.036), although there was no difference in the short-term response (β-CTX: P = 0.856; P1NP: P = 0.721; IL-6: P = 0.327). No other variable was significantly affected by CHO feeding during exercise. We conclude that CHO feeding during exercise attenuated the β-CTX and P1NP responses in the hours but not days following exercise, indicating an acute effect of CHO feeding on bone turnover.
authors.affiliation: Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom; craig.sale@ntu.ac.uk.
authors.forename: Craig
authors.initials: C
authors.lastname: Sale
authors.affiliation: Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom;
authors.forename: Ian
authors.initials: I
authors.lastname: Varley
authors.affiliation: Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom;
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Jones
authors.affiliation: Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom;
authors.forename: Ruth M
authors.initials: RM
authors.lastname: James
authors.affiliation: Norwich Medical School, University of East Anglia, Norwich, United Kingdom;
authors.forename: Jonathan C Y
authors.initials: JC
authors.lastname: Tang
authors.affiliation: Norwich Medical School, University of East Anglia, Norwich, United Kingdom; Norfolk and Norwich University Hospital, Norwich, United Kingdom; and.
authors.forename: William D
authors.initials: WD
authors.lastname: Fraser
authors.affiliation: Department of Occupational Medicine, HQ Army Recruiting and Training Division, Upavon, United Kingdom.
authors.forename: Julie P
authors.initials: JP
authors.lastname: Greeves
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D001862:Bone Resorption / Q000097:blood; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D024042:Collagen Type I / Q000378:metabolism; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects; D010446:Peptide Fragments / Q000378:metabolism; D011347:Procollagen / Q000378:metabolism; D012420:Running / Q000502:physiology*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D004040:Dietary Carbohydrates; C508600:IL6 protein, human; D015850:Interleukin-6; D010446:Peptide Fragments; D011347:Procollagen; C047202:procollagen Type I N-terminal peptide; D002118:Calcium
keywords: bone metabolism; carbohydrate; exercise; feeding; running