INFLUENCE OF D-PINTOL ON WHOLE BODY CREATINE RETENTION

Abstract

Creatine hyperaccumulation in muscle has been reported to be insulin dependent. The naturally occurring glycan D-pinitol has been reported to possess insulin-like effects. This study examined whether D-pinitol (InzitolTM) influences whole body creatine retention. 20 males with no history of creatine supplementation participated in this study. Subjects donated 24-h urine samples for 4-d. After an initial control day, subjects were matched and assigned to ingest in a single blind manner either a placebo (P = 4 × 5 g of dextrose), creatine monohydrate (CM = 4 × 5 g), creatine with low dose pinitol (LP = 4 × 5 g creatine + 2 × 0.5 g pinitol), for creatine with high dose pinitol (HP = 4 × 5 g creatine + 4 × 0.5 g pinitol) for 3-d. Additionally, another group ingested 2 × 0.5 g pinitol for 5-d followed by ingesting 4 × 5 g creatine + 2 × 0.5 g pinitol for 3-d (Pre P). Creatine retention was estimated by subtracting total urinary creatine excretion from total creatine intake over the 3-d period. Data were analyzed by ANOVA. Results revealed that cumulative creatine retention was significantly greater in the LP and Pre P groups (P = 0 ± 0; CM = 36.6 ± 9; LP = 49.7 ± 3; HP = 36.7 ± 13; Pre P = 46.7 ± 6 g, p = 0.001). This extrapolated to a significantly greater percentage of creatine retention in the LP and Pre P groups (P = 0 ± 0; CM = 61 ± 15; LP = 83 ± 5; HP = 61 ± 22; Pre P = 78 ± 9%, p = 0.001). These preliminary findings suggests that ingesting D- pinitol during creatine loading or prior to and during creatine loading may augment whole body creatine retention. Supported by Humanetics, Inc. (Minneapolis, MN)