Journal Logo

E16M FREE COMMUNICATION/POSTER CREATINE

EFFECTS OF LONG-TERM CREATINE SUPPLEMENTATION ON RENAL FUNCTION AND MUSCLE & LIVER ENZYME EFFLUX

Kreider, R FACSM1; Melton, C1; Rasmussen, C1; Greenwood, M1; Cantler, E1; Milnor, P1; Almada, A1

Author Information
Medicine & Science in Sports & Exercise: May 2001 - Volume 33 - Issue 5 - p S207
  • Free

Creatine has been reported to be an effective ergogenic aid. However, concerns have been raised regarding the long-term safety of creatine supplementation. This study examined the effects of long-term creatine supplementation on renal function and muscle/liver enzyme efflux. Over a 21 month period, 94 Division IA college football players (19 ± 1 yrs, 103 ± 3 kg) were administered in an open label manner creatine or non-creatine containing supplements following training sessions. Subjects who ingested creatine were administered 15.75 g/d of creatine monohydrate for 5-d and an average of 5 g/d thereafter. Fasting blood and 24-hour urine samples were collected at 0, 1, 1.5, 4, 6, 10, 12, 17, and 21 months of training. At the end of the study, subjects were categorized into groups that did not take creatine (n = 44) and subjects who took creatine for 0–6 months (mean 5.0 ± 1.8 months, n = 12), 7–12 months (mean 9.4 ± 3.6 months, n = 25), and 12–21 months (mean 18.1 ± 3.0 months, n = 13). Baseline and the subjects' last blood and urine samples were analyzed by repeated measures ANOVA. Results revealed that creatine supplementation had no significant effects on serum creatinine, urinary creatinine excretion, creatinine clearance, blood urea nitrogen (BUN), BUN/creatinine ratio, CK, LDH, AST, or ALT. These findings support contentions that short and long-term creatine supplementation does not adversely affect renal function or markers of muscle & liver damage. Supported by UM, MRS, EAS, SKW Trostberg & MRM

©2001The American College of Sports Medicine