Doping

THE IMPACT OF INHALED TERBUTALINE ON 3km RUNNING TIME TRIAL
PERFORMANCE
Whyte, G., Molphy, J., Chester, N. J., Dickinson, J. W., Loosemore, M.
Elite athletes have a higher prevalence of Exercise-induced bronchoconstriction
(EIB) than the general population. Treatment for EIB and asthma includes
inhalation of short acting β2 agonists which act to reverse the bronchoconstriction
of the airways. The majority of athletes treat symptoms of EIB through the use of salbutamol however, other β2 agonists, such as terbutaline, are available which are
longer acting and have fewer side effects. In contrast to salbutamol, salmeterol and
formoterol, therapeutic doses of the inhaled short acting β2 agonist, terbutaline
still requires a TUE. Limited research exists examining the ergogenic effect of
terbutaline. Accordingly, aim of the present study was to examine the effects of 2
mg and 4 mg inhaled terbutaline on exercise performance during a 3km running
time-trial.
Participants (8 males; age: 24.3 ± 2.4 years; weight: 77.6 ± 8 kg; height: 179.5 ±
4.3 cm, and 8 females; age: 22.4 ± 3 years; weight: 58.6 ± 6 kg; height: 163 ±
9.2 cm) completed three 3km time-trial in a randomised, single blind, repeated
measures design with a minimum of 7 days between trials. Prior to the test
participants were assigned to one of three groups:
(1) 8 inhalations of non-active inhalant (placebo);
(2) 4 inhalations of non-active inhalant plus 4 inhalations of terbutaline (2mg); or
(3) 8 inhalations of terbutaline (4mg).
In addition to performance variables, urine concentrations of terbutaline were
measured following each trial. There was no significant difference in completion
time between trials in either males or females following 2 mg or 4 mg of inhaled
terbutaline.
There was no difference in urine concentration following either 2 mg inhalation or 4
mg inhalation in males or females. There was a high individual variation in urine
concentration of terbutaline with a maximum value of 1250 ng/ml-1 following the
inhalation of 4 mg of terbutaline. In conclusion, terbutaline, when taken in
therapeutic doses (2 mg or 4 mg), does not improve 3 km running time-trial
performance in males or females.

https://wada-main-prod.s3.amazonaws.com/resources/files/final_report_11d8gw_dr._g._whyte.pdf