title: The effect of a pre-exercise carbohydrate meal on immune responses to an endurance performance run.
abstract: This study examined the effect of a pre-exercise meal with different glycaemic index (GI) and glycaemic load (GL) on immune responses to an endurance performance run. Eight men completed a preloaded 1 h run at 70 % VO2max on a level treadmill followed by a 10 km performance run on three occasions. In each trial, one of the three prescribed isoenergetic meals, i.e. high GI and high GL (H-H), high GI and low GL (H-L), or low GI and low GL (L-L) was consumed by the subjects 2 h before exercise. Carbohydrate intake (% of energy intake), GI, and GL were 65 %, 79.5, and 82.4 for H-H; 36 %, 78.5, and 44.1 for H-L; 65 %, 40.2, and 42.1 for L-L, respectively. The running time for the three trials was approximately 112 min at 70 % VO2max for the first hour and 76 % VO2max for the last 52 min. Consumption of pre-exercise high-carbohydrate meals (H-H and L-L) resulted in less perturbation of the circulating numbers of leucocytes, neutrophils and T lymphocyte subsets, and in decreased elevation of the plasma IL-6 concentrations immediately after exercise and during the 2 h recovery period compared with the H-L trial. These responses were accompanied by an attenuated increase in plasma IL-10 concentrations at the the end of the 2 h recovery period. The amount of carbohydrate consumed in the pre-exercise meal may be the most important influencing factor rather than the type of carbohydrate in modifying the immunoendocrine response to prolonged exercise.
authors.affiliation: Department of Sports Science and Physical Education, The Chinese University of Hong Kong, Shatin, NT, Hong Kong.
authors.forename: Ya-jun
authors.initials: YJ
authors.lastname: Chen
authors.forename: Stephen Heung-sang
authors.initials: SH
authors.lastname: Wong
authors.forename: Chun-kwok
authors.initials: CK
authors.lastname: Wong
authors.forename: Ching-Wan
authors.initials: CW
authors.lastname: Lam
authors.forename: Ya-jun
authors.initials: YJ
authors.lastname: Huang
authors.forename: Parco Ming-fai
authors.initials: PM
authors.lastname: Siu
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D018592:Cross-Over Studies; D016207:Cytokines / Q000097:blood; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000494:pharmacology*; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D038321:Glycemic Index; D006801:Humans; D007958:Leukocyte Count; D007962:Leukocytes / Q000187:drug effects* / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D009747:Nutritional Physiological Phenomena / Q000276:immunology* / Q000502:physiology; D010807:Physical Endurance / Q000276:immunology* / Q000502:physiology; D012420:Running / Q000502:physiology; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D016207:Cytokines; D004040:Dietary Carbohydrates