The NFL players union says the average number of injuries has risen during the 2010 season.

In a report released Friday called "Dangers of the Game of Football," the NFLPA says injuries increased from 3.2 to 3.7 per week per team and the share of players injured increased to 63 percent compared to a 2002-09 average of 59 percent.

The report also shows that 13 percent of all injuries required players to be placed on injured reserve this season, compared to an average of 10 percent for 2002-09. The union says that indicates the injuries which are occurring are more serious than in past years.

The analysis is based on data from NFL Weeks 1 through 16 from Football Outsiders, which compiles information from the publicly available weekly injury reports.

The NFL also compiles such data. Its numbers also show more players on IR than in recent years: 464 for the entire season, up from 388 the previous year, 416 in 2008 and 413 in 2007.

NFL spokesman Greg Aiello notes, however, that the injured reserve numbers don't always indicate the severity of injuries.

"Every year almost 2,600 players go through the system (32 teams x 80 players going into training camp) and a few hundred are put on injured reserve for different reasons," Aiello said. "That number could include everything from rookies put on IR for the season with injuries of differing severity to players with relatively minor injuries who then reach injury settlements with their teams and are released."

Union medical director Dr. Thom Mayer emphasized the dangers of the sport.

"We know that injuries are part of the game, but the more data and information we can gather on player health and safety, the more likely we are to make the game safer," Mayer said. "Player contracts are not guaranteed, even as injury rates rise, which means careers face sudden ends each time the ball is snapped."

The report shows that 37.7 percent of all injuries caused players to miss games, which was down .7 percent from the 2002-09 average. And 30 percent of players missed at least some game time, up 1 percent.

"I think the sheer size and athleticism of guys creates that," Cardinals receiver Larry Fitzgerald said at the Pro Bowl in Honolulu. "You got a guy moving at that speed, hitting somebody, more damage is going to be done. That's just the way football is. It's a violent game."

According to the union, under the current collective bargaining agreement that expires March 4, players are not fully protected from being released after sustaining a significant injury. Cleveland linebacker Scott Fujita, who went on injured reserve late in the 2010 season with a knee injury, said the danger of the game needs to be considered during negotiations for a new CBA.

"An NFL football field isn't a typical workplace, and we know we are facing significant risk when we play this game," Fujita said.

Vikings star running back Adrian Peterson blamed the emphasis on removing hits to the head and neck for the increase in injuries.

"I think the players are getting bigger, stronger, faster," Peterson said from Hawaii. "Then again, I think it's some of the rule changes. Guys are getting fined, $25,000, $50,000 for hits to the heads, so guys are going to try to go for the legs. Stuff like that — they make it to protect the quarterback, but it hurts the integrity of the game, too."


AP Sports Writer Jaymes Song in Honolulu contributed to this story.