TESTOSTERONE ENHANCED PERFORMANCES ARE LOST UPON CESSATION
Weatherby, R. P., Giorgi, A., & Kazlauskas, R. (May, 2002). Retention of performance gains following testosterone enanthate administration. Sixth IOC World Congress on Sport Sciences, abstract, p. 90.
Weight-training males (N = 21) were divided into to two groups and given weekly injections of testosterone enanthate (3.5 mg/kgBW) or saline placebo for 12 weeks. After cessation of injections, measures were continued for a further 12 weeks.
After 12 weeks of testosterone injections, the experimental group increased significantly more (22%) than the placebo group (9%) for the bench press. For 30-m sprint, the placebo group remained stable while the testosterone group decreased from 4.42 s to 4.33 s. There were no differences between groups in a 6-s cycle test or countermovement jump. After six weeks of cessation, the testosterone group’s strength gains had declined to 12% compared to 9% for the placebo. After 12 weeks, both groups showed only 8% improvement over the original value. Testosterone/epitestosterone ratios did not change over the duration of the study in the placebo group but changed from .96 to 15.12 in the testosterone group. The ratio declined back to nearly original values after 12 weeks of cessation. Overall, gains in bench press and T:ET ratio declined in a reciprocal manner to that of improvement. It is possible sprint gains reflected other changes (e.g., skill) not affected by testosterone.
Implications. Performance gains through testosterone supplementation are slow to take effect and are lost after cessation.
For these reasons, test levels that would be equivalent to a therapeutic dose should not be considered a drug offence.