Pilot study of serum inhibin B as a potential marker of testosterone doping in weight lifting men.

OBJECTIVE

The aim of this study was to explore effectors of the pituitary-testicular axis suitable as potential biochemical markers to screen for testosterone doping.

DESIGN

Pilot study with male bodybuilding athletes with a self-reported history of testosterone doping (repeated intramuscular administration of testosterone preparations, last injection 8 weeks or less ago) compared with an equal sized control group matched for sex, age, and body mass index.

SETTING

Endocrine outpatients.

PARTICIPANTS

Fifteen healthy young men of white background.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Inhibin B, testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH).

RESULTS

Although the levels of testosterone, LH, and FSH did not differ between the 2 groups, the serum concentrations of inhibin B in individuals with a history of testosterone doping were exclusively at or below the lower limit of the normal range for adult men (100-400 pg/mL). Inhibin B was significantly lower in those men who used testosterone for weight lifting (76.1 +/- 36.3 ng/L [mean +/- SD]) than in controls (182.1 +/- 35.4 ng/L).

CONCLUSION

A low concentration of serum inhibin B may reflect the application of exogenous testosterone and appears to be a potential marker associated with anabolic androgenic steroid doping.