Saturday, August 3, 2013
Searching for answers on NFL injury front
By Mike Sando
A run of high-profile injuries in the NFC West specifically and the NFL in general has focused attention on what can be done to prevent them.
John from Bakersfield, Calif., was among those raising the subject through the NFC West mailbag. He suggested the San Francisco 49ers and Baltimore Ravens might be additionally vulnerable at present after playing more games than other teams over the past couple seasons. Baltimore (38 games), San Francisco (37) and New England (37) have played the most games over that span.
"The Ravens this year gutted their defense and saw Dennis Pitta go down already, while the 49ers are reeling from all their injuries," John wrote. "The curse of Super Bowl losers and winners is the fact that most teams that go deep into the playoffs over a few years time play so many more games and get get beat up so much more than the tier of teams right below them. You have to really take your hat off to the Patriots for getting deep so often, but even they seem worn out at the end lately, and I believe it has to do with having to play the extra games. What do you think?"
San Francisco's Vernon Davis has been one of the NFL's most durable tight ends in recent seasons.
The thinking makes sense, but there are several factors to consider.
What about the additional offseason downtime players won through the collective bargaining agreement? Shouldn't that help offset injuries? But wait, might an extended run of inactivity make players additionally vulnerable to injury when they suddenly resume an intense practice schedule? The answers could be different for different players at different positions working under different head coaches with different conditioning programs and different practice schedules on different playing surfaces in different weather.
See where this is headed?
I'd like to see the relationship between total snaps played and injury rates for individual players over long periods of time, adjusted for age, position, body type, injury type, circumstances of injury and any other factors that might create different risk levels.
Pitta ranked 24th among NFL tight ends in snaps played over the 2011 and 2012 seasons, counting playoffs. His 1,384 snaps played over that two-year run fell far below the leaders. Ten tight ends played between 1,750 and more than 2,100 snaps over that span, led by the 49ers' Vernon Davis and followed closely by Jason Witten and Tony Gonzalez, three of the more durable tight ends around (a contributing factor in their presence atop the list of snaps played).
Merely correlating teams' total games played to future injury rates seems futile because rosters change and most teams play a similar number of games.
Twenty-five of the 32 teams played between 32 and 34 games over the 2010 and 2011 seasons. Those teams averaged 61.7 adjusted games lost to injury in 2012, according to Football Outsiders. The seven teams with between 35 and 37 games played over the period in question averaged 74.3 adjusted games lost in 2012, including a league-high 108.1 adjusted games lost by Green bay, which played a league-high 37 games over the previous two seasons.
What does that prove? Probably nothing. The six teams playing 34 games over the 2010 and 2011 seasons averaged 37.2 adjusted games lost in 2012, far below the 69.4 average for the 19 teams with 32 or 33 games played. That likely doesn't mean much, either.
The statistical correlation between 2010-11 games played and 2012 adjusted games lost to injury is .066, an insignificant figure. But we already knew that would be an imprecise way to secure the answers we're seeking. This is one area where the NFL and its teams will be pushing to collect and interpret data.