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Effects of glycerol and creatine hyperhydration on doping-relevant blood parameters.

Polyviou TP, Easton C, Beis L, Malkova D, Takas P, Hambly C, Speakman JR, Koehler K, Pitsiladis YP - Nutrients (2012)

Bottom Line: However, the scientific basis of the inclusion of Gly as a "masking agent" remains inconclusive.This hyperhydration did not significantly alter plasma volume or any of the doping-relevant blood parameters (e.g., hematocrit, Hb, reticulocytes and total Hb-mass) even when Gly was clearly detectable in urine samples.In conclusion, this study shows that supplementation with hyperhydrating solution containing Gly for 7 days does not significantly alter doping-relevant blood parameters.

View Article: PubMed Central - PubMed

Affiliation: Institute of Cardiovascular & Medical Sciences, College of Medicine, Veterinary and Life Sciences, University of Glasgow, UK. t.polyviou.1@research.gla.ac.uk

ABSTRACT
Glycerol is prohibited as an ergogenic aid by the World Anti-Doping Agency (WADA) due to the potential for its plasma expansion properties to have masking effects. However, the scientific basis of the inclusion of Gly as a "masking agent" remains inconclusive. The purpose of this study was to determine the effects of a hyperhydrating supplement containing Gly on doping-relevant blood parameters. Nine trained males ingested a hyperhydrating mixture twice per day for 7 days containing 1.0 g·kg(-1) body mass (BM) of Gly, 10.0 g of creatine and 75.0 g of glucose. Blood samples were collected and total hemoglobin (Hb) mass determined using the optimized carbon monoxide (CO) rebreathing method pre- and post-supplementation. BM and total body water (TBW) increased significantly following supplementation by 1.1 ± 1.2 and 1.0 ± 1.2 L (BM, P < 0.01; TBW, P <0.01), respectively. This hyperhydration did not significantly alter plasma volume or any of the doping-relevant blood parameters (e.g., hematocrit, Hb, reticulocytes and total Hb-mass) even when Gly was clearly detectable in urine samples. In conclusion, this study shows that supplementation with hyperhydrating solution containing Gly for 7 days does not significantly alter doping-relevant blood parameters.

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Mean ± S.D. values of Hb concentration (g·dL−1), Hct (%), OFF-hr score and Ret% pre- (0 h) and post-supplementation (2–24 h) of the hyperhydrating solution containing Gly, Cr and Glu. N = 6, ↓: ingestion of 1st and 2nd solution at 0 h and 4 h, respectively. * Significant (P < 0.05) difference between pre- and post-supplementation.
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nutrients-04-01171-f006: Mean ± S.D. values of Hb concentration (g·dL−1), Hct (%), OFF-hr score and Ret% pre- (0 h) and post-supplementation (2–24 h) of the hyperhydrating solution containing Gly, Cr and Glu. N = 6, ↓: ingestion of 1st and 2nd solution at 0 h and 4 h, respectively. * Significant (P < 0.05) difference between pre- and post-supplementation.

Mentions: BM was significantly higher at the end of the experimental day and in the morning of the next day compared to baseline; 0.4 ± 0.1 and 0.6 ± 0.4 kg, respectively (P < 0.01). Conversely, TBW measured with BIA was not significantly affected by supplementation (ANOVA, P = 0.1). Figure 5 shows the pattern of Gly excretion following the supplementation. Before supplementation, urinary [Gly] was very low and similar in all subjects and ranged from 0.0 to 0.2 mg·mL−1. Urinary [Gly] increased from 0.0 ± 0.1 mg·mL−1 (0 h) to 11.2 ± 8.1 mg·mL−1 in the first urine sample (2 h) and 16.4 ± 3.5 mg·mL−1 in the final sample taken after supplementation of the first solution (4 h). At 4 h, a second drink was administrated and urinary [Gly] increased further to 18.4 ± 5.6 mg·mL−1 in the next urine collection (6 h). Urinary [Gly] peaked at 8 h (21.3 ± 4.1 mg·mL−1) and then started decreasing gradually towards baseline. Urinary [Gly] returned to baseline (0.0 ± 0.0 mg·mL−1) after 16 h in all subjects. Figure 6 shows responses of blood markers pre- and post-supplementation. Despite the urinary changes in [Gly] over time, concentrations of Hb, Hct and Ret% were not significantly different between baseline and any other time point (ANOVA, Hb: P = 0.3; Hct: P = 0.3; Ret%: P = 0.9). The OFF-hr score was significantly lower after 75 min of observation compared to baseline (P = 0.02). PV changes calculated using values of Hb and Hct measured at baseline and at each time point of observation (assuming no change in red cell mass during the supplementation period) increased by ~2.7% at the end of the supplementation day but this increase was not significantly different (P = 0.9).


Effects of glycerol and creatine hyperhydration on doping-relevant blood parameters.

Polyviou TP, Easton C, Beis L, Malkova D, Takas P, Hambly C, Speakman JR, Koehler K, Pitsiladis YP - Nutrients (2012)

Mean ± S.D. values of Hb concentration (g·dL−1), Hct (%), OFF-hr score and Ret% pre- (0 h) and post-supplementation (2–24 h) of the hyperhydrating solution containing Gly, Cr and Glu. N = 6, ↓: ingestion of 1st and 2nd solution at 0 h and 4 h, respectively. * Significant (P < 0.05) difference between pre- and post-supplementation.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3475229&req=5

nutrients-04-01171-f006: Mean ± S.D. values of Hb concentration (g·dL−1), Hct (%), OFF-hr score and Ret% pre- (0 h) and post-supplementation (2–24 h) of the hyperhydrating solution containing Gly, Cr and Glu. N = 6, ↓: ingestion of 1st and 2nd solution at 0 h and 4 h, respectively. * Significant (P < 0.05) difference between pre- and post-supplementation.
Mentions: BM was significantly higher at the end of the experimental day and in the morning of the next day compared to baseline; 0.4 ± 0.1 and 0.6 ± 0.4 kg, respectively (P < 0.01). Conversely, TBW measured with BIA was not significantly affected by supplementation (ANOVA, P = 0.1). Figure 5 shows the pattern of Gly excretion following the supplementation. Before supplementation, urinary [Gly] was very low and similar in all subjects and ranged from 0.0 to 0.2 mg·mL−1. Urinary [Gly] increased from 0.0 ± 0.1 mg·mL−1 (0 h) to 11.2 ± 8.1 mg·mL−1 in the first urine sample (2 h) and 16.4 ± 3.5 mg·mL−1 in the final sample taken after supplementation of the first solution (4 h). At 4 h, a second drink was administrated and urinary [Gly] increased further to 18.4 ± 5.6 mg·mL−1 in the next urine collection (6 h). Urinary [Gly] peaked at 8 h (21.3 ± 4.1 mg·mL−1) and then started decreasing gradually towards baseline. Urinary [Gly] returned to baseline (0.0 ± 0.0 mg·mL−1) after 16 h in all subjects. Figure 6 shows responses of blood markers pre- and post-supplementation. Despite the urinary changes in [Gly] over time, concentrations of Hb, Hct and Ret% were not significantly different between baseline and any other time point (ANOVA, Hb: P = 0.3; Hct: P = 0.3; Ret%: P = 0.9). The OFF-hr score was significantly lower after 75 min of observation compared to baseline (P = 0.02). PV changes calculated using values of Hb and Hct measured at baseline and at each time point of observation (assuming no change in red cell mass during the supplementation period) increased by ~2.7% at the end of the supplementation day but this increase was not significantly different (P = 0.9).

Bottom Line: However, the scientific basis of the inclusion of Gly as a "masking agent" remains inconclusive.This hyperhydration did not significantly alter plasma volume or any of the doping-relevant blood parameters (e.g., hematocrit, Hb, reticulocytes and total Hb-mass) even when Gly was clearly detectable in urine samples.In conclusion, this study shows that supplementation with hyperhydrating solution containing Gly for 7 days does not significantly alter doping-relevant blood parameters.

View Article: PubMed Central - PubMed

Affiliation: Institute of Cardiovascular & Medical Sciences, College of Medicine, Veterinary and Life Sciences, University of Glasgow, UK. t.polyviou.1@research.gla.ac.uk

ABSTRACT
Glycerol is prohibited as an ergogenic aid by the World Anti-Doping Agency (WADA) due to the potential for its plasma expansion properties to have masking effects. However, the scientific basis of the inclusion of Gly as a "masking agent" remains inconclusive. The purpose of this study was to determine the effects of a hyperhydrating supplement containing Gly on doping-relevant blood parameters. Nine trained males ingested a hyperhydrating mixture twice per day for 7 days containing 1.0 g·kg(-1) body mass (BM) of Gly, 10.0 g of creatine and 75.0 g of glucose. Blood samples were collected and total hemoglobin (Hb) mass determined using the optimized carbon monoxide (CO) rebreathing method pre- and post-supplementation. BM and total body water (TBW) increased significantly following supplementation by 1.1 ± 1.2 and 1.0 ± 1.2 L (BM, P < 0.01; TBW, P <0.01), respectively. This hyperhydration did not significantly alter plasma volume or any of the doping-relevant blood parameters (e.g., hematocrit, Hb, reticulocytes and total Hb-mass) even when Gly was clearly detectable in urine samples. In conclusion, this study shows that supplementation with hyperhydrating solution containing Gly for 7 days does not significantly alter doping-relevant blood parameters.

Show MeSH
Related in: MedlinePlus