MANKATO, Minn. - Embracing the challenge has always been a part of Adrian Peterson's persona.
Following his quick comeback from reconstructive knee surgery, surpassing the 2,000-yard mark and the league MVP award last season for the Minnesota Vikings, Peterson said Friday he'd eagerly accept another test: for human growth hormone.
The NFL and the players union have been working on an agreement for HGH testing procedures. Supplemental HGH is a banned substance but difficult to detect. Peterson said he's been hoping for a long time the league would put the test in place. He's seen and heard the accusations of cheating but said he's "all natural" and "clean as a whistle."
Peterson said he doesn't mind the skepticism and actually considers it a compliment.
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