title: A comparative analysis between the effects of galactose and glucose supplementation on endurance performance.
abstract: OBJECTIVE
  To determine beneficial effects of short-term galactose (GAL) supplementation over a 50:50 glucose-maltodextrin (GLUC) equivalent on self-paced endurance cycling performance.
  
  
  METHODS
  On 2 separate occasions, subjects performed a 100-km self-paced time trial (randomized and balanced order). This was interspersed with four 1-km and four 4-km maximal efforts reflecting the physical requirements of racing. Before each trial 38±3 g of GAL or GLUC was ingested in a 6% concentrate fluid form 1 hr preexercise and then during exercise at a rate of 37±3 g/hr. Performance variables were recorded for all 1- and 4-km efforts, all interspersed intervals, and the total 100-km distance. Noninvasive indicators of work intensity (heart rate [HR] and rating of perceived exertion) were also recorded.
  
  
  RESULTS
  Times taken to complete the 100-km performance trial were 8,298±502 and 8,509±578 s (p=.132), with mean power outputs of 271±37 and 256±45 W (p=.200), for GAL and GLUC, respectively. Mean HR did not differ (GAL 157±7 and GLUC 157±7 beats/min, p=.886). A main effect of carbohydrate (CHO) type on time to complete 4-km efforts occurred, with no CHO Type×Effort Order interaction observed. No main effect of CHO type or interaction of CHO Type×Sequential Order occurred for 1-km efforts.
  
  
  CONCLUSIONS
  A 6% GAL drink does not enhance performance time during a self-paced cycling performance trial in highly trained endurance cyclists compared with a formula typically used by endurance athletes but may improve the ability to produce intermediate self-paced efforts.
authors.affiliation: School of Sport and Exercise, Massey University Manawatu (Turitea), Manawatu, New Zealand.
authors.forename: Paul W
authors.initials: PW
authors.lastname: Macdermid
authors.forename: Stephen
authors.initials: S
authors.lastname: Stannard
authors.forename: Dean
authors.initials: D
authors.lastname: Rankin
authors.forename: David
authors.initials: D
authors.lastname: Shillington
mesh_terms: D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D001642:Bicycling; D015930:Diet Records; D019587:Dietary Supplements / Q000009:adverse effects; D004311:Double-Blind Method; D005690:Galactose / Q000008:administration & dosage* / Q000009:adverse effects; D005947:Glucose / Q000008:administration & dosage* / Q000009:adverse effects; D006339:Heart Rate; D006801:Humans; D008297:Male; D058573:Performance-Enhancing Substances / Q000008:administration & dosage* / Q000009:adverse effects; D010807:Physical Endurance / Q000502:physiology*; D005082:Physical Exertion; D010809:Physical Fitness / Q000502:physiology*; D013997:Time Factors
chemical_list: D058573:Performance-Enhancing Substances; D005947:Glucose; D005690:Galactose