title: Effect of Breakfast Omission on Energy Intake and Evening Exercise Performance.
abstract: BACKGROUND
  Breakfast omission may reduce daily energy intake. Exercising fasted impairs performance compared with exercising after breakfast, but the effect breakfast omission has on evening exercise performance is unknown. This study assessed the effect of omitting breakfast on evening exercise performance and within-day energy intake.
  
  
  METHODS
  Ten male, habitual breakfast eaters completed two trials in a randomized, counterbalanced order. Subjects arrived at the laboratory in an overnight-fasted state and either consumed or omitted a 733 ± 46 kcal (3095 ± 195 kJ) breakfast. Ad libitum energy intake was assessed at 4.5 h (lunch) and 11 h (dinner). At 9 h, subjects completed a 30-min cycling exercise at approximately 60% VO2peak, followed by a 30-min maximal cycling performance test. Food was not permitted for subjects once they left the laboratory after dinner until 0800 h the following morning. Acylated ghrelin, GLP-1(7-36), glucose, and insulin were assessed at 0, 4.5, and 9 h. Subjective appetite sensations were recorded throughout.
  
  
  RESULTS
  Energy intake was 199 ± 151 kcal greater at lunch (P < 0.01) after breakfast omission compared with that after breakfast consumption and tended to be greater at dinner after consuming breakfast (P = 0.052). Consequently, total ad libitum energy intake was similar between trials (P = 0.196), with 24-h energy intake 19% ± 5% greater after consuming breakfast (P < 0.001). Total work completed during the exercise performance test was 4.5% greater after breakfast (314 ± 53 vs 300 ± 56 kJ; P < 0.05). Insulin was greater during breakfast consumption at 4.5 h (P < 0.05), with no other interaction effect for hormone concentrations.
  
  
  CONCLUSIONS
  Breakfast omission might be an effective means of reducing daily energy intake but may impair performance later that day, even after consuming lunch.
authors.affiliation: School of Sport, Exercise, and Health Sciences, Loughborough University, Loughborough, Leicestershire, UNITED KINGDOM.
authors.forename: David J
authors.initials: DJ
authors.lastname: Clayton
authors.forename: Asya
authors.initials: A
authors.lastname: Barutcu
authors.forename: Claire
authors.initials: C
authors.lastname: Machin
authors.forename: David J
authors.initials: DJ
authors.lastname: Stensel
authors.forename: Lewis J
authors.initials: LJ
authors.lastname: James
mesh_terms: D000215:Acylation; D001066:Appetite / Q000502:physiology; D001786:Blood Glucose / Q000378:metabolism; D062408:Breakfast; D002149:Energy Intake; D015444:Exercise / Q000502:physiology*; D005215:Fasting; D054439:Ghrelin / Q000097:blood; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D013997:Time Factors; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D054439:Ghrelin; D007328:Insulin