title: Effect of training and 15-, 25-, and 42-km contests on the skeletal muscle content of adenine and guanine nucleotides, creatine phosphate, and glycogen.
abstract: Thirty-four nonathletic volunteers (23 males and 11 females) were subjected to a training program aimed at completing a marathon run within 18-20 months after the onset of training. During the course of the training the content of ATP, creatine phosphate, GTP, GDP, NAD+, purine bases, and glycogen in biopsyspecimens of m. vastus lateralis increased. No major gender differences were observed. The tissue content of adenine and guanine nucleotides such as ATP, ADP, AMP, GTP, and GDP did not change when measured within 6 h after a 15-, 25-, or 42-km contest. During 9 days after the 42-km contest the muscle content of the adenine nucleotides showed a slight, but significant decrease. Glycogen levels were found to be decreased to 90%, 60%, and 62% of their pre-contest values after the 15-, 25-, and 42-km contests, respectively. Nine days after the expenditures supranormal levels were only measured following the 15-km contest. The tissue content of glycogen returned to pre-contest levels after the 25- and 42-km races. The present findings indicate that, from a biochemical point of view, expenditures such as 15-, 25-, and 42-km contests are very well tolerated by the m. vastus lateralis in recreative runners subjected to a training with a maximal duration of 18-20 months.
authors.affiliation: Department of Human Biology/Institute Sportsmedicine Limburg, Maastricht, The Netherlands.
authors.forename: G J
authors.initials: GJ
authors.lastname: van der Vusse
authors.forename: G M
authors.initials: GM
authors.lastname: Janssen
authors.forename: W A
authors.initials: WA
authors.lastname: Coumans
authors.forename: H
authors.initials: H
authors.lastname: Kuipers
authors.forename: R J
authors.initials: RJ
authors.lastname: Does
authors.forename: F
authors.initials: F
authors.lastname: ten Hoor
mesh_terms: D000227:Adenine Nucleotides / Q000378:metabolism*; D000328:Adult; D004734:Energy Metabolism; D005069:Evaluation Studies as Topic; D005260:Female; D006003:Glycogen / Q000378:metabolism*; D006150:Guanine Nucleotides / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000378:metabolism*; D010725:Phosphocreatine / Q000378:metabolism*; D010806:Physical Education and Training; D010807:Physical Endurance; D012420:Running
chemical_list: D000227:Adenine Nucleotides; D006150:Guanine Nucleotides; D010725:Phosphocreatine; D006003:Glycogen