title: Periodization of Carbohydrate Intake: Short-Term Effect on Performance.
abstract: BACKGROUND
  "Sleep-low" consists of a sequential periodization of carbohydrate (CHO) availability-low glycogen recovery after "train high" glycogen-depleting interval training, followed by an overnight-fast and light intensity training ("train low") the following day. This strategy leads to an upregulation of several exercise-responsive signaling proteins, but the chronic effect on performance has received less attention. We investigated the effects of short-term exposure to this strategy on endurance performance.
  
  
  METHODS
  Following training familiarization, 11 trained cyclists were divided into two groups for a one-week intervention-one group implemented three cycles of periodized CHO intake to achieve the sleep-low strategy over six training sessions (SL, CHO intake: 6 g·kg-1·day-1), whereas the control group consumed an even distribution of CHO over the day (CON). Tests were a 2 h submaximal ride and a 20 km time trial.
  
  
  RESULTS
  SL improved their performance (mean: +3.2%;p< 0.05) compared to CON. The improvement was associated with a change in pacing strategy with higher power output during the second part of the test. No change in substrate utilization was observed after the training period for either group.
  
  
  CONCLUSIONS
  Implementing the "sleep-low" strategy for one week improved performance by the same magnitude previously seen in a three-week intervention, without any significant changes in selected markers of metabolism.
authors.affiliation: Laboratory of Sport, Expertise and Performance, French National Institute of Sport, Expertise and Performance (INSEP), 75012 Paris, France. laurie-anne.marquet@insep.fr.|Université Côte d'Azur, LAMHESS, 06205 Nice, France. laurie-anne.marquet@insep.fr.
authors.forename: Laurie-Anne
authors.initials: LA
authors.lastname: Marquet
authors.affiliation: Laboratory of Sport, Expertise and Performance, French National Institute of Sport, Expertise and Performance (INSEP), 75012 Paris, France. hausswirthc@gmail.com.
authors.forename: Christophe
authors.initials: C
authors.lastname: Hausswirth
authors.affiliation: Laboratory of Sport, Expertise and Performance, French National Institute of Sport, Expertise and Performance (INSEP), 75012 Paris, France. odeline.molle@insep.fr.
authors.forename: Odeline
authors.initials: O
authors.lastname: Molle
authors.affiliation: Mary MacKillop Institute for Health Research, Centre for Exercise and Nutrition, Australian Catholic University, Melbourne, VIC 3065, Australia. John.Hawley@acu.edu.au.|Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool L3 5UA, UK. John.Hawley@acu.edu.au.
authors.forename: John A
authors.initials: JA
authors.lastname: Hawley
authors.affiliation: Mary MacKillop Institute for Health Research, Centre for Exercise and Nutrition, Australian Catholic University, Melbourne, VIC 3065, Australia. louise.burke@ausport.gov.au.|Sports Nutrition, Australian Institute of Sport (AIS), Belconnen, ACT 2617, Australia. louise.burke@ausport.gov.au.
authors.forename: Louise M
authors.initials: LM
authors.lastname: Burke
authors.affiliation: Laboratory of Sport, Expertise and Performance, French National Institute of Sport, Expertise and Performance (INSEP), 75012 Paris, France. eve.tiollier@insep.fr.
authors.forename: Eve
authors.initials: E
authors.lastname: Tiollier
authors.affiliation: Université Côte d'Azur, LAMHESS, 06205 Nice, France. brisswalter@unice.fr.
authors.forename: Jeanick
authors.initials: J
authors.lastname: Brisswalter
mesh_terms: D000293:Adolescent; D000328:Adult; D056352:Athletes; D001642:Bicycling / Q000502:physiology; D004032:Diet; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D015444:Exercise; D005080:Exercise Test; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D010507:Periodicity; D010807:Physical Endurance / Q000187:drug effects*; D064133:Sports Nutritional Physiological Phenomena; D055815:Young Adult
chemical_list: D004040:Dietary Carbohydrates
keywords: carbohydrate; cycling time trial; lipid oxidation; perception of effort; performance; trained athletes; training