The drug test for exogenous administration of testosterone is based on the testosterone/epitestosterone
ratio (T/E) in urine. Physiological and psychological stresses may alter plasma testosterone
concentrations. The question is to know how much the psychological conditions of competition
can modify the T/E ratio. In order to study this issue, 20 athletes practising modern
pentathlon participated in a study designed to determine the effects of a pistol shooting
trial on their hormonal response. Pistol shooting induces a high psychological stress
without increasing energy expenditure. Venous blood samples were drawn before and
after the trial according to the usual drug testing procedure. Athletes were separated
into two groups: a group of young athletes (n = 10; mean age 19 ± 0.3 years) and another
group of aged subjects (n = 10; mean age 45 ± 1.5 years). The rise in plasma testosterone
concentrations reached 75 % in older subjects versus 55 % in younger ones. The plasma
luteinizing hormone (LH) concentrations were not influenced by the trial. After shooting
trial the elevation in Cortisol concentrations was greater for older subjects than
for younger ones (273 ± 30 ng · ml-1 vs 173 ± 7 ng · ml-1). The catecholamine response was identical in both groups. The urinary T/E ratio
remained unchanged after the shooting trial and always remained lower than the International
Olympic Committee limit of 6. These results indicate that the psychological stress
associated with competition increases the production of steroid hormones (testosterone,
Cortisol), and that this phenomenon is more pronounced in older athletes. These hormonal
changes do not influence the urinary excretion of steroid metabolites used as criterion
for drug testing.
Doping control - stress - testosterone - luteinizing hormone - catecholamines - Cortisol
- pistol shooting
