title: Post-exercise appetite was affected by fructose content but not glycemic index of pre-exercise meals.
abstract: The purpose of this study was to investigate whether both glycemic index (GI) and breakfast fructose content affect appetite during the postprandial period and recovery period after 1 hr of brisk walking. Ten healthy young men (age: 21.7 ± 1.5 y, body mass index: 20.9 ± 1.1 kg∙m(-2), VO2max: 53.7 ± 3.7 mL∙kg(-1)∙min(-1)) completed 1 hr of brisk walking at 46% VO2max 2 hr after eating one of three isocaloric breakfasts: a low-GI breakfast not including fructose content (LGI), a low-GI breakfast including fructose beverage (LGIF) and a high-GI breakfast (HGI). All breakfasts provided 1.0 g∙kg(-1) body weight carbohydrates, and the calculated GI values for the three breakfasts were 41, 39, and 72, respectively. In the LGIF and HGI trials, approximately 25% of participants' energy was derived from either fructose or glucose beverage. Appetite scores were measured every 30 min during the 2-hr postprandial period and 1-hr recovery period. During the postprandial period, the incremental areas under the blood response curve values of glucose and insulin were higher in the HGI trial, compared with those in the LGI and LGIF trials. At 30 and 60 min during the recovery period, the appetite scores were lower in the LGIF trial than those in the LGI and HGI trials. No differences were observed between the LGI and HGI trials. Breakfast fructose content, rather than GI, seems to affect appetite during the recovery period after 1 hr of brisk walking.
authors.affiliation: Department of Health and Physical Education, Hong Kong Institute of Education, Hong Kong. Electronic address: fhsun@ied.edu.hk.
authors.forename: Feng-Hua
authors.initials: FH
authors.lastname: Sun
authors.affiliation: Department of Sports Science and Physical Education, Chinese University of Hong Kong, Hong Kong.
authors.forename: Stephen Heung-Sang
authors.initials: SH
authors.lastname: Wong
authors.affiliation: Dong Ying Vocational Institute, Shan Dong, China.
authors.forename: Zhi-Gang
authors.initials: ZG
authors.lastname: Liu
mesh_terms: D001066:Appetite / Q000502:physiology*; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D062408:Breakfast; D018592:Cross-Over Studies; D005632:Fructose / Q000008:administration & dosage*; D038321:Glycemic Index; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D009043:Motor Activity; D019518:Postprandial Period; D011795:Surveys and Questionnaires; D016138:Walking; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D007328:Insulin; D005632:Fructose
keywords: Appetite score; Breakfast; Brisk walking