title: ENDURANCE TRAINING IN FASTING CONDITIONS: BIOLOGICAL ADAPTATIONS AND BODY WEIGHT MANAGEMENT.
abstract: BACKGROUND
  in the majority of sports the athlete is required to achieve optimal conditions both at a muscular and metabolic level as well as in body composition, increasing the lean body mass and maintaining a low body fat mass. In this context, different training protocols have been proposed in order to reduce body fat content, by maximizing fat use instead of glycogen.
  
  
  OBJECTIVE
  to verify if the training while fasting favours the use of fatty acids due to the low glycogen levels, allowing an improvement in the performance ant the control of body weight.
  
  
  RESULTS
  protocols have been published, differing in time periods and exercise intensity. In addition, several markers ranging from gene expression analysis to determination of circulating parameters have been assessed in order to interpret the results. Discusion: at low intensities of endurance-based exercises, adipose tissue lipolysis and muscle fat oxidation rate seem to be higher in fasting than in fed state. On the other hand, glucose metabolism is adapted in order to save glycogen stores, possibly through gluconeogenesis activation. Finally, it has been observed that protein degradation is mainly downregulated. Only one study analyses changes in body composition after fasting during long periods, thus further work is necessary to demonstrate that this is the best method to control body fat.
authors.affiliation: Biochemistry and Cell Therapy Unit, Institute of Bioengineering, University Miguel Hernández, Elche.. nvicente@umh.es.
authors.forename: Néstor
authors.initials: N
authors.lastname: Vicente-Salar
authors.affiliation: Researcher University Isabel I. Performance and Sport Nutrition Research Group. ELIKAESPORT Nutrition, Innovation & Sport. Spain.. nvicente@umh.es.
authors.forename: Aritz
authors.initials: A
authors.lastname: Urdampilleta Otegui
authors.affiliation: Biochemistry and Cell Therapy Unit, Institute of Bioengineering, University Miguel Hernández, Elche.. nvicente@umh.es.
authors.forename: Enrique
authors.initials: E
authors.lastname: Roche Collado
mesh_terms: D000220:Adaptation, Biological / Q000502:physiology*; D056352:Athletes; D001835:Body Weight / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005215:Fasting / Q000502:physiology*; D005947:Glucose / Q000378:metabolism; D006801:Humans; D010807:Physical Endurance / Q000502:physiology*
chemical_list: D005947:Glucose