Adam Vinatieri
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How has Adam Vinatieri – at 40 the oldest active NFL player – stuck around for so long? It helps that he's a placekicker, but his position isn't the only key. "He's well-known for his training schedule and for his participation in conditioning exercises and drills with the remainder of the team," Williams says. "Kickers in years past were kind of a bit of a laughingstock with regards to their fitness level and being real football players. But we have a current crop of kickers represented by Adam's generation who really sort of consider themselves as real athletes."