title: Effect of coingestion of fat and protein with carbohydrate feedings on muscle glycogen storage.
abstract: Dietary guidelines for achieving optimal muscle glycogen storage after prolonged exercise have been given in terms of absolute carbohydrate (CHO) intake (8-10 g.kg-1.day-1). However, it is of further interest to determine whether the addition of fat and protein to carbohydrate feedings affects muscle glycogen storage. Eight well-trained triathletes [23.1 +/- 2.0 (SE) yr; 74.0 +/- 3.4 kg; peak O2 consumption = 4.7 +/- 0.4 l/min] undertook an exercise trial (2 h at 75% peak O2 consumption, followed by four 30-s sprints) on three occasions, each 1 wk apart. For 24 h after each trial, the subjects rested and were assigned to the following diets in randomized order: control (C) diet (high glycemic index CHO foods; CHO = 7 g.kg-1.day-1), added fat and protein (FP) diet (C diet + 1.6 g.kg-1.day-1 fat + 1.2 g.kg-1.day-1 protein), and matched-energy diet [C diet + 4.8 g.kg-1.day-1 additional CHO (Polycose) to match the additional energy in the FP diet]. Meals were eaten at t = 0, 4, 8, and 21 h of recovery. The total postprandial incremental plasma glucose area was significantly reduced after the FP diet (P < 0.05). Serum free fatty acid and plasma triglyceride responses were significantly elevated during the FP trial (P < 0.05). There were no differences between trials in muscle glycogen storage over 24 h (C, 85.8 +/- 2.7 mmol/kg wet wt; FP, 80.5 +/- 8.2 mmol/kg wet wt; matched-energy, 87.9 +/- 7.0 mmol/kg wet wt).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Australian Institute of Sport, Belconnen.
authors.forename: L M
authors.initials: LM
authors.lastname: Burke
authors.forename: G R
authors.initials: GR
authors.lastname: Collier
authors.forename: S K
authors.initials: SK
authors.lastname: Beasley
authors.forename: P G
authors.initials: PG
authors.lastname: Davis
authors.forename: P A
authors.initials: PA
authors.lastname: Fricker
authors.forename: P
authors.initials: P
authors.lastname: Heeley
authors.forename: K
authors.initials: K
authors.lastname: Walder
authors.forename: M
authors.initials: M
authors.lastname: Hargreaves
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D004040:Dietary Carbohydrates / Q000378:metabolism*; D004041:Dietary Fats / Q000378:metabolism*; D004044:Dietary Proteins / Q000378:metabolism*; D004435:Eating; D005227:Fatty Acids / Q000097:blood; D006003:Glycogen / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000097:blood; D009132:Muscles / Q000378:metabolism*; D014280:Triglycerides / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D005227:Fatty Acids; D007328:Insulin; D014280:Triglycerides; D006003:Glycogen