At Pro Bowl, Peterson doesn't plan to let up - Article Photos 1/1

FILE - Minnesota Vikings running back Adrian Peterson (28) walks off the field after an NFL wild card playoff football game against the Green Bay Packers in this Jan. 5, 2013 file photo taken in Green Bay, Wis. Peterson says motivation to play hard so soon after the physically taxing season is often missing for many, but he argues that letting up is more dangerous. (AP Photo/Mike Roemer)