In September, 2006 Jansen appeared on the HBO show Costas Now where in an interview with Bob Costas he stated that in his estimation between 15-20% of the league used illegal performance enhancing drugs. Jansen stated that the use of illegal substances was on the rise because the use of human growth hormone injections which are not tested for by the NFL.
He later recanted this estimation, saying that he felt 15-to-20 percent was a low amount and not realizing the significant numbers of players that a 15-to-20 percent figure would represent.
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