NEW YORK—As concerns about the health risks involved for youth players continue to rise, a new poll revealed Thursday that a growing majority of NFL players would not allow their sons to play preseason football. “Now that we know how dangerous it really is, how could I in good conscience let my 7-year-old son go out there and play in a preseason football game?” said Pittsburgh Steelers linebacker Lawrence Timmons, echoing the sentiments of many NFL players who told reporters that the potentially devastating health costs associated with participating in a full four-game preseason outweigh any reward, especially at the professional level.