Prevalence, knowledge and attitudes towards using sports supplements among young athletes.

BACKGROUND: The aim of this international study was to investigate the prevalence of the use of sports supplements among young athletes, as well as their knowledge and attitudes towards sports supplementation. METHODS: Organized survey study testing the level of knowledge, attitudes, beliefs and practices concerning the use of sports supplements was administered to 348 athletes, 15-18 year olds from 4 countries competing in 18 sports at the international level. RESULTS: The prevalence rate of the intake of sports supplements was 82.2%, with the protein supplements being predominant (54.5%). Coaches were identified as the primary source of information regarding supplementation (41.4%). The enhancement of athletic performance (35.4%) was the major motivation for the supplements intake. The majority of athletes (72.1%) were aware of associated health risks. The young athletes possess varying levels of knowledge regarding their own supplementation. The obtained data about the level of knowledge were statistically analyzed using the correspondence analysis. Less than 40% of athletes had the knowledge about the proper and intended use of protein, creatine, amino acids, beta alanine and glutamine, while they had greater understanding about vitamins and minerals, sports drinks and caffeine. The athletes in developed countries had greater access and utilization of professional resources such as dieticians. Young athletes are still unfamiliar with WADA regulations (55.5%), and the misuse of sports supplements represents an ethical dilemma for some. CONCLUSION: These findings indicate the necessity of a comprehensive education of all team members about sports supplements and careful supervision of the athletic development of young athletes.

Hydrophilic interaction chromatography coupled to tandem mass spectrometry as a method for simultaneous determination of guanidinoacetate and creatine.

The biosynthesis of creatine (Cr) is closely related to the bioavailability of guanidinoacetate (GAA). The lack of one or the other may compromise their role in the energy transport and cell signaling. A reliable estimate of their levels in biological samples is imperative since they are important markers of many metabolic disorders. Therefore, a new LC-MS/MS method for simultaneous determination and quantification of GAA and Cr by multiple reaction monitoring (MRM) mode was developed based on the hydrophilic interaction chromatography (HILIC) and response surface methodology (RSM) for the optimization of chromatographic parameters. The optimized parameters ensured good separation of these similar, very polar molecules (chromatographic resolution > 1.5) without prior derivatization step in a short analysis run (6 min). The developed method was validated to ensure accurate (R, 75.1-101.6%), precise (RSD < 20%) and low quantification (LOQ of 0.025 µg mL-1 for GAA and 0.006 µg mL-1 for Cr) of the tested analytes and the use of matrix-matched calibration eliminated variable effects of complex matrices such as human plasma and urine. Therefore, this method can be implemented in medical laboratories as a tool for the diagnostics of creatine deficiencies and monitoring of guanidinoacetate and creatine supplementation regimes in biological samples.