title: Antioxidant and oligonutrient status, distribution of amino acids, muscle damage, inflammation, and evaluation of renal function in elite rugby players.
abstract: BACKGROUND
  Our study investigated the biochemical and anthropometric characteristics in elite athletes of rugby union based in the south of France during the different periods of the competition to identify metabolic and biochemical adaptations to particular lifestyle conditions.
  
  
  METHODS
  Participants included 35 players in 2008 and 43 players in 2009. Biochemical variables [creatinine, uric acid, creatine kinase (CK), alanine aminotransferase, aspartate aminotransferase, C-reactive protein] were evaluated. Specific protein levels (albumin, acid α-glycoprotein, prealbumin), vitamins (A, E, C), antioxidant enzymes [glutathione peroxidase (GPx), superoxide dismutase (SOD)], oligoelements (Zn, Se, Cu, erythrocyte magnesium), homocysteine (Hcy), carnitine and the distribution of amino acids were specifically determined for our study during a pre-competition period (September 2008 and 2009).
  
  
  RESULTS
  Globally, no deficit was observed for vitamins, oligonutrients and amino acids levels. The high SOD and GPx activities in rugby players suggest a presence of oxidative stress of exercise. The evaluation of renal function should be used with caution because of the interaction between creatinine and lean body mass. In addition, a profound effect of intense exercise on the CK values was reported to establish specific reference values for athletes. The analysis of the biological variation allows optimization of the interpretation of the changes from an increased or decreased baseline value from a season to the other one.
  
  
  CONCLUSIONS
  The conclusions of present study were: 1) the necessity of rugby-specific reference intervals for CK and creatinine parameters; 2) the use of enzymatic creatinine for Modification of Diet in Renal Disease (MDRD) and CKD-EPI, or cystatin C to improve glomerular filtration rate estimation; 3) to take into account the oxidative stress testifying of a bad recovery; and 4) better to take care the nutritional status of the players by adapting needs and amino acids supplementations but also to consider a follow-up of oxidative stress and antioxidants according our results.
authors.affiliation: Biochemistry Laboratory, Lapeyronie Hospital, Montpellier, France.
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Gorce-Dupuy
authors.forename: Carlos
authors.initials: C
authors.lastname: Vela
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Badiou
authors.forename: Anne Sophie
authors.initials: AS
authors.lastname: Bargnoux
authors.forename: Christophe
authors.initials: C
authors.lastname: Josse
authors.forename: Nicolas
authors.initials: N
authors.lastname: Roagna
authors.forename: Martine
authors.initials: M
authors.lastname: Delage
authors.forename: Françoise
authors.initials: F
authors.lastname: Michel
authors.forename: Marie Hélène
authors.initials: MH
authors.lastname: Vernet
authors.forename: Dominique
authors.initials: D
authors.lastname: Destizons
authors.forename: Jean Paul
authors.initials: JP
authors.lastname: Cristol
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000378:metabolism*; D000975:Antioxidants / Q000378:metabolism*; D056352:Athletes; D002331:Carnitine / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D005538:Football / Q000502:physiology*; D005919:Glomerular Filtration Rate; D006710:Homocysteine / Q000097:blood; D006801:Humans; D007249:Inflammation / Q000209:etiology / Q000378:metabolism; D007677:Kidney Function Tests; D008019:Life Style; D008297:Male; D009132:Muscles / Q000293:injuries*; D009752:Nutritional Status; D014815:Vitamins / Q000097:blood
chemical_list: D000596:Amino Acids; D000975:Antioxidants; D014815:Vitamins; D006710:Homocysteine; D002331:Carnitine