Actually, HGH is only one of the myriad thigns used as performance enhancing substances by athletes. If it was only HGH they had to worry about, there wouldnt be a drug problem in sport anymore 
In fact, as the piece alludes to, many of the agents they cant even test for, however tests including blood and urine can test for slight changes in general body chemistry which result from drug use.

In fact, as the piece alludes to, many of the agents they cant even test for, however tests including blood and urine can test for slight changes in general body chemistry which result from drug use.

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