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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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Related in: MedlinePlus

Schematic representation of procedures during experimental trials.
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nutrients-04-01171-f001: Schematic representation of procedures during experimental trials.

Mentions: All procedures described below and shown schematically in Figure 1 were carried out on all visits to the laboratory (familiarization, pre- and post-supplementation) with the exception of the TBW measurement, which was only performed in the pre-, and post-supplementation trials. Measurements during the 1st visit to the laboratory (familiarization trial) were only performed to ensure that the participants were introduced to and were comfortable with all procedures and therefore data from familiarization trials were not reported. On arrival to the laboratory, participants provided a baseline urine sample before nude BM was recorded. Euhydration was confirmed, prior to the start of each experiment, by measuring urine osmolality and all subjects were found to be euhydrated (155 ± 55 mOsm/L). Following this, a 21 G cannula was introduced into a superficial vein of the anticubital fossa of the subject’s right arm. Blood samples (10.0 mL) were taken before and after a rebreathing procedure used to measure total Hb mass (tHb-mass) (see protocol below) [16,19,20]. Participants had adopted a supine position 10 min prior to each blood sampling as posture change induces PV shifts, which in turn can influence concentration based measures such as [Hb] and Hct [21] and PV derived from tHb, [Hb] and Hct. Participants were then asked to orally ingest 0.5 g·kg−1 BM deuterium oxide (D2O) in the morning after a baseline urine sample had been collected. D2O is a stable (nonradioactive) isotope of hydrogen, distinguished by its additional neutron. Once orally ingested, D2O mixes with body water and is eliminated from the body along with unlabeled water. The calculation of water intake from D2O elimination is based on the assumptions described by Fjeld et al. [22]. D2O for the present study was purchased from the Doubly Labeled Water (DLW) Resource Center, University of Aberdeen. Participants were instructed to empty their bladder completely at 5 h post D2O ingestion and in order to evaluate the isotopic decay in body water; a urine sample was collected again in a dry plastic container 6 h after ingestion of D2O. Participants were allowed breakfast, a light lunch and were allowed to pass urine and drink as normal within the 6 h period, as consumption of food and fluids during the 6 h period has been shown not to affect the post D2O measurement of TBW [23] For purposes of analysis, the investigator transferred 2.0 mL from all urine samples from the plastic containers to glass vessels and stored at −20 °C until analysis. Urine samples were then sent in one batch to the University of Aberdeen for isotopic analysis by an isoprime isotope ratio mass spectrometer (Isoprime Limited, Earl Road, Cheadle Hulme, Cheadle, UK) coupled to a Eurovector gas chromatatographer (GC; Eurovector, Via Torana, Milan, Italy) fitted with an HT300A autosampler (HTA, Via del Mella, Brescia, Italy) as previously described [24].


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)

Schematic representation of procedures during experimental trials.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

nutrients-04-01171-f001: Schematic representation of procedures during experimental trials.
Mentions: All procedures described below and shown schematically in Figure 1 were carried out on all visits to the laboratory (familiarization, pre- and post-supplementation) with the exception of the TBW measurement, which was only performed in the pre-, and post-supplementation trials. Measurements during the 1st visit to the laboratory (familiarization trial) were only performed to ensure that the participants were introduced to and were comfortable with all procedures and therefore data from familiarization trials were not reported. On arrival to the laboratory, participants provided a baseline urine sample before nude BM was recorded. Euhydration was confirmed, prior to the start of each experiment, by measuring urine osmolality and all subjects were found to be euhydrated (155 ± 55 mOsm/L). Following this, a 21 G cannula was introduced into a superficial vein of the anticubital fossa of the subject’s right arm. Blood samples (10.0 mL) were taken before and after a rebreathing procedure used to measure total Hb mass (tHb-mass) (see protocol below) [16,19,20]. Participants had adopted a supine position 10 min prior to each blood sampling as posture change induces PV shifts, which in turn can influence concentration based measures such as [Hb] and Hct [21] and PV derived from tHb, [Hb] and Hct. Participants were then asked to orally ingest 0.5 g·kg−1 BM deuterium oxide (D2O) in the morning after a baseline urine sample had been collected. D2O is a stable (nonradioactive) isotope of hydrogen, distinguished by its additional neutron. Once orally ingested, D2O mixes with body water and is eliminated from the body along with unlabeled water. The calculation of water intake from D2O elimination is based on the assumptions described by Fjeld et al. [22]. D2O for the present study was purchased from the Doubly Labeled Water (DLW) Resource Center, University of Aberdeen. Participants were instructed to empty their bladder completely at 5 h post D2O ingestion and in order to evaluate the isotopic decay in body water; a urine sample was collected again in a dry plastic container 6 h after ingestion of D2O. Participants were allowed breakfast, a light lunch and were allowed to pass urine and drink as normal within the 6 h period, as consumption of food and fluids during the 6 h period has been shown not to affect the post D2O measurement of TBW [23] For purposes of analysis, the investigator transferred 2.0 mL from all urine samples from the plastic containers to glass vessels and stored at −20 °C until analysis. Urine samples were then sent in one batch to the University of Aberdeen for isotopic analysis by an isoprime isotope ratio mass spectrometer (Isoprime Limited, Earl Road, Cheadle Hulme, Cheadle, UK) coupled to a Eurovector gas chromatatographer (GC; Eurovector, Via Torana, Milan, Italy) fitted with an HT300A autosampler (HTA, Via del Mella, Brescia, Italy) as previously described [24].

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