Perhaps the increase in severe injuries, if there is in fact such an increase, has something to do with the type of players coming into the league. This is strictly speculation, but might be some food for thought:
There are country-big/country-strong players. They're naturally, genetically who they are, or close to it anyway. Then there are the heavily manufactured players, who by training, diet and/or HGH and other non-banned supplements have added muscle, mass and speed to the maximum carrying capacity (or beyond?) what mother nature intended for them, with miniscule BMI numbers added into the bargain.
We know advanced training techniques have reached down into the elite "national" high school programs these days, where HGH is also prevalent. Competition is ever more intense for BCS conference jobs as a stepping stone to the pros.
Perhaps, as the average manufactured % of a typical NFL player has inched up, the components of the body resistant to conditioning, diet or drugs (and therefore unchanged or minimally changed from what mother nature intended) are being put under ever increasing stresses...that would be tendons, cartilage and bone. And what is the relationship between a low BMI and incidence of injury?
