title: Total PYY and GLP-1 responses to submaximal continuous and supramaximal sprint interval cycling in men.
abstract: Exercise-induced changes in appetite-regulating hormones may be intensity-dependent, however a clear dose-response relationship has not been established. The purpose of this study was to examine changes in anorexigenic markers (total PYY and GLP-1) in response to rest or exercise at submaximal and supramaximal intensities. Ten active males completed four experimental sessions in randomized order: 1) Moderate intensity continuous training (MICT; 30 min cycling at 65% VO2max); 2) High intensity continuous training (HICT; 30 min cycling at 85% VO2max); 3) Sprint interval training (SIT; 6 × 30 s "all-out" cycling bouts with 4 min recovery periods); 4) Control (CTRL; no exercise). Blood samples were obtained immediately pre- and post-exercise, as well as 90-min post-exercise for the measurement of total PYY and GLP-1. Subjective hunger was assessed using a visual analog scale pre-breakfast and at the three blood sampling time-points. Total PYY concentrations increased immediately post-exercise following both HICT (P = 0.006) and SIT (P < 0.001) versus CTRL, while SIT was also greater (P = 0.005) compared to MICT. Total GLP-1 concentrations changed similarly across time-points (P < 0.001), with no differences between sessions (P = 0.280). Perceptions of hunger also changed similarly across time-points (P < 0.001) with no differences between trials (P = 0.085). These findings suggest that total PYY increases only after high-intensity exercise and exhibits a greater responsiveness to SIT compared to moderate-intensity exercise. Compensatory increases in hunger do not seem to occur at any exercise intensity. These findings support a dose-response relationship between exercise intensity and total PYY, though the effects on total GLP-1 and hunger perceptions seem unclear.
authors.affiliation: Department of Kinesiology and Physical Education, Faculty of Science, Wilfrid Laurier University, Waterloo, Ontario, N2L 3C5, Canada. Electronic address: thazell@wlu.ca.
authors.forename: Tom J
authors.initials: TJ
authors.lastname: Hazell
authors.affiliation: Department of Kinesiology and Physical Education, Faculty of Science, Wilfrid Laurier University, Waterloo, Ontario, N2L 3C5, Canada. Electronic address: isla9020@mylaurier.ca.
authors.forename: Hashim
authors.initials: H
authors.lastname: Islam
authors.affiliation: Department of Kinesiology and Physical Education, Faculty of Arts and Science, University of Lethbridge, Lethbridge, Alberta, T1K 3M4, Canada. Electronic address: jillian.rhys@gmail.com.
authors.forename: Jillian R
authors.initials: JR
authors.lastname: Hallworth
authors.affiliation: Department of Kinesiology and Physical Education, Faculty of Arts and Science, University of Lethbridge, Lethbridge, Alberta, T1K 3M4, Canada. Electronic address: jennifer.copeland@uleth.ca.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Copeland
mesh_terms: D000328:Adult; D001069:Appetite Regulation; D001642:Bicycling; D015415:Biomarkers / Q000097:blood; D018592:Cross-Over Studies; D004797:Enzyme-Linked Immunosorbent Assay; D052216:Glucagon-Like Peptide 1 / Q000097:blood* / Q000378:metabolism; D000072696:High-Intensity Interval Training; D006801:Humans; D006815:Hunger; D008297:Male; D019894:Peptide YY / Q000097:blood* / Q000378:metabolism; D055815:Young Adult
chemical_list: D015415:Biomarkers; D019894:Peptide YY; D052216:Glucagon-Like Peptide 1
keywords: Aerobic exercise; Anorexigenic; Appetite; High-intensity; Satiety; Sprint interval training