Is Creatine Safe ? Creatine supplementation does not affect clinical health markers in football players.

Creatine supplementation does not affect clinical health markers in football players.

Cancela P1, Ohanian C, Cuitiño E, Hackney AC.

Author information

• 1Lic. Biochemistry, Facultad de Ciencias, Universidad de la República, Uruguay. cohanian@netgate.com.uy

Erratum in

• Br J Sports Med. 2009 Oct 1;43(10):764.
• Br J Sports Med. 2010 Oct;44(13):e4.

PURPOSE:

To study the effects of 8-week creatine monohydrate (CrM) supplementation on blood and urinary clinical health markers in football players.

METHODS:

14 football players were randomly assigned in a double-blinded fashion to Cre (n = 7) or Pla (n = 7) group. The Cre group ingested 15 g/day of CrM for 7 days and 3 g/day for the remaining 49 days, whereas the Pla group ingested maltodextrin following the same protocol. Football-specific training was performed during the study. Total body mass was determined and blood and urine samples were analysed for metabolic, hepatic, renal and muscular function markers, before and after supplementation.

RESULTS:

A gain of total body mass was observed after CrM intake, but not with placebo. Blood and urinary markers remained within normal reference values. There were no significant changes in renal and hepatic markers after CrM intake. However, total creatine kinase (CK) activity significantly increased, and uric acid level tended to decrease after CrM use. Likewise, serum glucose decreased in the Cre group following supplementation. No significant differences in urine parameters were found in either group after supplementation.

CONCLUSIONS:

8 weeks of CrM supplementation had no negative effects on blood and urinary clinical health markers in football players. Properties of CrM may, however, be associated with an increase in CK activity, improving the efficiency for ATP resynthesis, a phenomenon indirectly confirmed by the decreasing tendency in uric acid concentration. Furthermore, CrM seems to slightly influence glucoregulation in trained subjects.