mixing shakes before workouts

[loua65]

is it alright to mix a protein shake and a creatine shake an hour before lifting? My usual workouts are about an hour long, so will they last two hours or can they go bad or something?

thnx

[taffer]

i mix my whey shake before i workout, put it in the fridge for 1-2hours so when i get back i can chug it!!

[Cogar]

They will be fine. The only problem is if you do not keep them cool you may get some bacteria growth if everything was not sanitary when you mixed it.

[sk8_d0g]

Creatine turns into it's waste product, creatinine, pretty quick when it's in liquid. Just take the powder to the gym in a nalgene or something, shake it up with some water right after your workout and down it. easy enough.

[Cogar]

Ninety percent creatine degradation was observed within 45 days for room temperature samples.

AAPS PharmSciTech. 2003;4(2):E25. Related Articles, Links

Evaluation of the stability of creatine in solution prepared from effervescent creatine formulations.

Ganguly S, Jayappa S, Dash AK.

Department of Pharmacy Sciences, School of Pharmacy and Health Professions, Creighton University, Omaha, NE 68178, USA.

The objectives of this study were to determine the cause of the crystallization in a large volume creatine supplement solution made from effervescent powders containing di-creatine citrate, and to characterize these crystals using thermal analyses and x-ray diffractometry. Creatine effervescent powders were dissolved in deionized water (pH 6.2) and stored both at room temperature (RT) (25 degrees C) and refrigerated condition (4 degrees C) over a period of 45 days. Creatine concentration was determined using high-performance liquid chromatography (HPLC). Intrinsic dissolution and saturated solubility of creatine, creatine monohydrate, and di-creatine citrate in water were determined and compared. Crystal growth was detected only in the refrigerated samples on the seventh day of storage. Differential Scanning Calorimetry (DSC) and x-ray diffraction (XRD) studies revealed that the crystals formed were of creatine monohydrate. Ninety percent creatine degradation was observed within 45 days for RT samples. However, at refrigerated condition this degradation was 80% within the same time period. The pH of the RT samples also increased from 3.6 to 4.5 during storage. No such increase was observed in the case of refrigerated samples. The intrinsic dissolution rate constants of the compounds decreased in the following order: di-creatine citrate > creatine > creatine monohydrate. In conclusion, di-creatine citrate used in effervescent formulation dissociates to creatine in aqueous solution and eventually crystallizes out as creatine monohydrate. Significant decrease in solubility and effect of pH contribute to this crystallization process.

Publication Types:

* Evaluation Studies


PMID: 12916907 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/entrez/q..._uids=12916907

[Cogar]

"Substantial conversion of creatine into creatinine was noticed in liquid formulation." Note: this refers to products that are sold in liquid form and have probably been in solution for weeks if not months.

J Pharm Biomed Anal. 2002 Jul 31;29(5):939-45. Related Articles, Links

A simple LC method with UV detection for the analysis of creatine and creatinine and its application to several creatine formulations.

Dash AK, Sawhney A.

Department of Pharmacy Sciences, School of Pharmacy and Allied Health Professions, Creighton University, 2500 California Plaza, Omaha, NE 68178, USA. adash@creighton.edu

The objective of this study was to develop a simple and sensitive LC method for the determination of creatine and creatinine in various creatine supplement formulations. The chromatographic system comprised of a LC-600 pump, SCL-6B system controller, and SPD-6AV detector (Shimadzu, Japan). The mobile phase consisted of 0.045 M ammonium sulfate in water. The chromatographic separation was achieved at ******t temperature on a Betabasic C-18 column (250 x 4.6 mm, Keystone Sci.). The flow rate was maintained at 0.75 ml/min and effluents are monitored at 205 nm. 4-(2-Aminoethyl)benzene sulfonamide was used as an internal standard (IS). This method required less than 7 min of chromatographic time. The standard curves were linear over the concentration range of 1-100 microg/ml for creatine and 2-100 microg/ml for creatinine, respectively. The relative standard deviations (RSD) for the within-day and day-to-day precision for creatine were within 1.0-4.6 and 2.2-4.7%, respectively. The RSD for the accuracy of creatine assay was in the range of 2.4-4.7%. The RSD values for the within-day precision, day-to-day precision and accuracy for creatinine validation were 1.7-4.4, 2.3-5.4 and 2.4-4.8%, respectively. This method was used to determine: (i) the creatine concentration in various marketed products; (ii) saturated solubility of various creatine salts; and (iii) stability of creatine in aqueous solution. In conclusion, a simple and sensitive LC method with UV detection was developed for the simultaneous determination of creatine and creatinine in formulations. Di-creatine citrate salt showed a higher aqueous solubility (at 25 degrees C) as compared to creatine and creatine monohydrate. Some of the over-the-counter (OTC) products tested contained a very low level of creatine in contrast to their label claim. Substantial conversion of creatine into creatinine was noticed in liquid formulation.

PMID: 12093528 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/entrez/q..._uids=12093528