Development and validation of an UHPLC-MS/MS method for extended serum steroid profiling in female populations.

Quantitative endogenous steroid profiling in blood appears as a complementary approach to the urinary module of the World Anti-Doping Agency's Athlete Biological Passport Steroidal Module for the detection of testosterone doping. To refine this approach further, a UHPLC-MS/MS method was developed for the simultaneous determination of 14 free and 14 conjugated steroids in serum. The method was validated for quantitative purposes with satisfactory results in terms of selectivity, linearity range, trueness, precision and combined uncertainty (<20%).

A systematic review of glomerular hyperfiltration assessment and definition in the medical literature.

Background And Objectives: Evaluation of glomerular hyperfiltration (GH) is difficult; the variable reported definitions impede comparisons between studies. A clear and universal definition of GH would help in comparing results of trials aimed at reducing GH. This study assessed how GH is measured and defined in the literature.

Effect of multiple oral doses of androgenic anabolic steroids on endurance performance and serum indices of physical stress in healthy male subjects.

Anabolic androgenic steroids (AAS) are doping agents that are mostly used for improvement of strength and muscle hypertrophy. In some sports, athletes reported that the intake of AAS is associated with a better recovery, a higher training load capacity and therefore an increase in physical and mental performances. The purpose of this study was to evaluate, the effect of multiple doses of AAS on different physiological parameters that could indirectly relate the physical state of athletes during a hard endurance training program.

Use of isotope ratio mass spectrometry to detect doping with oral testosterone undecanoate: inter-individual variability of 13C/12C ratio.

The metabolic effect of multiple oral testosterone undecanoate (TU) doses over 4 weeks was assessed in seven voluntary men. The protocol was designed to detect accumulation of the substance by choosing the appropriate spot urines collections time and to study the urinary clearance of the substance after weeks of treatment. Urines were analysed by a new GC/C/isotope ratio mass spectrometry (IRMS) method to establish the delta(13)C-values of testosterone metabolites (androsterone and etiocholanolone) together with an endogenous reference compound (16(5alpha)-androsten-3alpha-ol).

Effects of high-intensity exercises on 13C-nandrolone excretion in trained athletes.

Objective: Nandrolone is an anabolic steroid widely used in several sports. The numerous nandrolone positive cases in the recent years (International Olympic Committee statistics) led to several studies in the antidoping field. Nevertheless, essential questions pertaining to nandrolone endogenous production, the effects of physical exercise on the excretion of nandrolone metabolites, and contamination from nutritional supplements must still be addressed.

[13C]Nandrolone excretion in trained athletes: interindividual variability in metabolism.

Background: Nandrolone is one of the most abused anabolic steroids, and its use in doping is increasing, as revealed by numerous positive cases during recent years in various sports. Different authors have reported the possible natural production of nandrolone metabolites in humans, and some of these authors argued that exhaustive exercise could increase nandrolone production in the body or induce dehydration and consequently lead to an increase of nandrolone metabolites in urine.

Methods: Volunteers (n = 22) ingested two 25-mg doses of [(13)C]nandrolone at 24-h intervals and collected urine specimens for 5 days.

Assessment of physical activity with a pedometer and its relationship with VO2max among adolescents in Switzerland.

Objectives: In the absence of a gold standard, the assessment of physical activity in children remains difficult. To record physical activity with a pedometer and to examine to what extent it is correlated with VO2max.

Methods: Survey on physical activity and fitness; 233 Swiss adolescents aged 11 to 15 carried a pedometer (Pedoboy) during seven consecutive days.