title: Short-term creatine supplementation does not reduce increased homocysteine concentration induced by acute exercise in humans.
abstract: OBJECTIVE
  The purpose of the study is to evaluate the effects of creatine supplementation on homocysteine (Hcy) plasma levels after acute exercise in humans.
  
  
  METHODS
  Twenty-three young (under-20) soccer players were divided into 2 groups: creatine (Cr)- and placebo (Pla)-supplemented groups. The supplementation was performed in double-blind controlled manner using creatine or placebo tablets with 0.3 g/kg during 7 days. Before and after 7 days of supplementation, the athletes performed an acute high-intensity sprint exercise (two consecutive running-based anaerobic sprint test protocol consisted in 6 × 35 m sprint with 10 s between them). Blood samples were collected before and after 7 days of supplementation as well as 0 and 1 h after exercise protocol.
  
  
  RESULTS
  Homocysteine concentration significant increased (P < 0.05) 1 h after acute exercise (18%). Acute exercise also decreased red blood cell S-adenosylmethionine (SAM) 30% with no changes in SAM/SAH ratio. Seven days of creatine supplementation were able to increase (P < 0.05) plasma creatine concentration (Pla 130.1 ± 21.7 vs Cr 1,557.2 ± 220.3 μmol/L) as well as decrease (P < 0.05) plasma guanidinoacetic acid (33%). Controversially, creatine supplementation did not change Hcy plasma level after 7-day supplementation (Pla 6.9 ± 0.2 vs Cr 7.2 ± 0.2 μmol/L) or after acute exercise (Pla 8.2 ± 0.3 vs Cr 8.4 ± 0.3 μmol/L). No changes in plasma vitamin B12 and folate as well as cysteine and methionine were found.
  
  
  CONCLUSIONS
  Seven days of creatine supplementation does not avoid increased plasma Hcy induced by acute sprint exercise in humans.
authors: Laboratory of Nutrition and Metabolism, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Av. Bandeirantes 3900, Ribeirão Prêto, Sao Paulo, Brazil, deminice@ig.com.br.
authors: Rafael
authors: R
authors: Deminice
authors: Flávia Troncon
authors: FT
authors: Rosa
authors: Gabriel Silveira
authors: GS
authors: Franco
authors: Selma Freirede Carvalho
authors: SF
authors: da Cunha
authors: Ellen Cristini
authors: EC
authors: de Freitas
authors: Alceu Afonso
authors: AA
authors: Jordao
mesh_terms: D000293:Adolescent; D003401:Creatine / Q000008:administration & dosage* / Q000097:blood; D003545:Cysteine / Q000097:blood; D019587:Dietary Supplements; D004311:Double-Blind Method; D002149:Energy Intake; D015444:Exercise; D005247:Feeding Behavior; D005492:Folic Acid / Q000097:blood; D005998:Glycine / Q000031:analogs & derivatives / Q000097:blood; D064368:Healthy Volunteers; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D008715:Methionine / Q000097:blood; D012436:S-Adenosylmethionine / Q000097:blood; D012916:Soccer; D014805:Vitamin B 12 / Q000097:blood
chemical_list: D006710:Homocysteine; D012436:S-Adenosylmethionine; D005492:Folic Acid; D008715:Methionine; C004946:glycocyamine; D003545:Cysteine; D003401:Creatine; D014805:Vitamin B 12; D005998:Glycine