<P> Patellar tendinitis (knee pain) is considered an overused injury that also happens to other athletes of virtually every sport . It is a common problem that football players develop and can usually be treated by a quadriceps strengthening program . Jumping activities place particularly high strains on the tendon and with repetitive jumping, tearing and injury of the tendon can occur . The chronic injury and healing response results in inflammation and localized pain . </P> <P> Although levels of depression and pain in retired football players are on par with the societal average, some players suffer from post-retirement chronic injuries . Head injuries are a particular concern . </P> <P> The average life expectancy or lifespan of an American football NFL player has been reported to be extremely low, only 53 to 59 years depending on playing position . However, a 2012 study reported that retired NFL players have a lower death rate than men in the general population . An oft - cited life expectancy of 58 years has been claimed by Sports Illustrated to be based on a myth . According to a 2007 study, which also claims that little supporting data is available, retired American football players had "long and fulfilling careers with no apparent long - term detrimental effects on physical or mental health scores despite a high prevalence of arthritis". One explanation is that "life expectancy" is ambiguous: it may in some contexts refer to the expected age of death of a player, and in other contexts to the expected remaining number of life years . </P> <P> As for association football, a 2011 German study found that German national team players live 1.9 years less than the general male population . </P>

What is the average life expectancy of an nfl player
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