You can't. Although you can make players think twice with random drug tests, you cant fully get rid of them.
steroids
Drugs slower the nervous system.
Drugs in sports came around 1970.
steriods
ROIDS
steroids
Meradona.
steroids
Barack obama.
weed
the "punishment" for taking any type of band drugs can range from a number of games suspend to being band from the sport ...
Drugs induce artificial stimulation of body in sportsmen.