Urinary creatine and methylamine excretion following 4 x 5 g x day(-1) or 20 x 1 g x day(-1) of creatine monohydrate for 5 days.
In this study, we examined the effect of two creatine monohydrate supplementation regimes on 24-h urinary creatine and methylamine excretion. Nine male participants completed two trials, separated by 6 weeks. Participants ingested 4 x 5 g x day(-1) creatine monohydrate for 5 days in one trial and 20 x 1 g x day(-1) for 5 days in the other. We collected 24-h urine samples on 2 baseline days (days 1-2), during 5 days of supplementation (days 3-7), and for 2 days post-supplementation (days 8-9). Urine was assayed for creatine using high-performance liquid chromatography and methylamine using gas chromatography. Less creatine was excreted following the 20 x 1 g x day(-1) regime (49.25 +/- 10.53 g) than the 4 x 5 g x day(-1) regime (62.32 +/- 9.36 g) (mean +/- s; P < 0.05). Mean total excretion of methylamine (n = 6) over days 3-7 was 8.61 +/- 7.58 mg and 24.81 +/- 25.76 mg on the 20 x 1 g x day(-1) and 4 x 5 g x day(-1) regimes, respectively (P < 0.05). The lower excretion of creatine using 20 x 1 g x day(-1) doses suggests a greater retention in the body and most probably in the muscle. Lower and more frequent doses of creatine monohydrate appear to further attenuate formation of methylamine.
School of Science and Technology, Nottingham Trent University, Nottingham, UK. craig.sale@ntu.ac.uk
Craig
C
Sale
Roger C
RC
Harris
James
J
Florance
Alain
A
Kumps
Robertine
R
Sanvura
Jacques R
JR
Poortmans
D000328:Adult; D015331:Cohort Studies; D003401:Creatine / Q000008:administration & dosage* / Q000652:urine*; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008297:Male; D008744:Methylamines / Q000652:urine*; D055815:Young Adult
D008744:Methylamines; C027451:methylamine; D003401:Creatine