Differences in Consumption Behaviour of Dietary Supplements in Competitive Athletes Depends on Sports Discipline.

BACKGROUND: The consumption of dietary supplements (DS) is widespread among the general population and competitive athletes. However, only a few competitive athletes seek information from experts about the effects and use of DS. Furthermore, it is currently unknown whether certain sports have a higher affinity for DS than others. METHODS: This study aimed to identify differences between different sports categories and subgroups that may have a very high affinity for DS. For this purpose, competitive athletes were surveyed. The survey included the type of sport, the training frequency, the number of competitions, the consumption behaviour of five DS categories (general health, regeneration promotion, performance enhancement, booster, and weight loss) as well as personal data such as biological sex and age. Subsequently, correlations, configural frequencies (CFA), and multiple correspondence analyses (MCA) were used to identify subgroups with a high affinity of consumption behaviour. RESULTS: A total of 409 questionnaires could be evaluated. It was found that all DS categories except weight loss were related. In addition, it was observed that in sports from the power category and from the endurance category, there was even higher consumption behaviour than in other sports categories. Male power athletes in particular have a higher affinity for consuming DS than other subgroups. CONCLUSIONS: This study shows that there is a clear different consumption behaviour depending on the type of sport. Male power athletes in particular are the subgroup with the greatest consumption behaviour and therefore require special education on the effects and use of DS. This subgroup in particular should receive increased attention in counselling on DS to minimise the possible risks of DS use.

Proton transport in functionalised additives for PEM fuel cells: contributions from atomistic simulations.

The conventional polymer electrolyte membrane (PEM) materials for fuel cell applications strongly rely on temperature and pressure conditions for optimal performance. In order to expand the range of operating conditions of these conventional PEM materials, mesoporous functionalised SiO(2) additives are developed. It has been demonstrated that these additives themselves achieve proton conductivities approaching those of conventional materials. However, the proton conduction mechanisms and especially factors influencing charge carrier mobility under different hydration conditions are not well known and difficult to separate from concentration effects in experiments. This tutorial review highlights contributions of atomistic computer simulations to the basic understanding and eventual design of these materials. Some basic introduction to the theoretical and computational framework is provided to introduce the reader to the field, the techniques are in principle applicable to a wide range of other situations as well. Simulation results are directly compared to experimental data as far as possible.

Proton conductivity of SO3 H-functionalized benzene-periodic mesoporous organosilica.

The proton conductivity of benzene-periodic mesoporous silica (PMO) materials functionalized with sulfonic acid groups is investigated using experimental and theoretical techniques. The SO(3) H functionalization of pristine benzene-PMO is realized by three different pathways based on a grafting method in which surface silanol groups and/or benzene rings are used to anchor SO(3) H groups for enhanced proton conductivity. The functionalized material is experimentally characterized using X-ray diffraction, small-angle neutron scattering, and argon adsorption isotherms. After pressing the functionalized benzene-PMOs into pellets, the proton conductivity is deduced from Bode plots of impedance spectra taken in the temperature range of 333-413 K at 100% relative humidity. Using quantum mechanical approaches for selected proton-conduction mechanisms, the free energy barriers for proton transport as well as the local water environment at the surface are calculated. These calculations indicate that different mechanisms from purely bulk water transport are important for the benzene-PMO proton conduction, in agreement with experimental data.