The NFL is the most physically taxing league in one of the world's most physically demanding sports.
There is a reason why running backs have one of the shortest shelf lives of any position in any sport, as the pounding of getting hit hard 15 to 20 times per game becomes too much for these players.
Tom Brady has managed to play near-injury-free football for 13 years now, and much of that has to do with his ability to get the ball out quickly, but it also has to do with his offensive line's ability to keep him from taking too many hits.
In 2012, the New England Patriots have been able to establish an effective running game that has limited defenses to just eight sacks through four games.
Stevan Ridley, and now Brandon Bolden, have led the Patriots ground game in 2012, and their combined 491 yards on the ground have helped give the Patriots the eighth-ranked rushing attack in football. In a league that has become more quarterback dependent than ever, any way to keep your signal-caller from getting hit is a step in the right direction.
At age 35, Brady is far from the spring chicken he used to be—a fact made evident by the way he lumbered towards his first rushing touchdown of the season during Week 4's win over the Buffalo Bills. Brady has said he wants to play until he's 40 and, in the world of advanced training and medicine we live in now, that is entirely possibly.
However, this new, more balanced offensive style could prolong he career even past that magic number.
So far in 2012, the Patriots' running backs (and Brady) have carried 137 times, good for second-best in the NFL. This an improvement over last season's 20th-best number, and shows that the Patriots are taking steps towards making it a bigger part of the their game plan.
While Bill Belichick would never admit this, he knows that Brady is the most important player he has, and that keeping him around for as long as he can be effective should be their second-biggest concern (after winning games).
Every game has its own individual game plan, and Belichick likely rests easier at night knowing that he can have Brady turn around and hand the ball off to Bolden and Ridley 38 times per game and not lose anything in terms of offensive production.
As Brady closes in on that magic number in his head, he should consider the state of the team around him before looking to hang up the cleats. Should this running attack still be as effective as it is now when that time comes and Brady can still sling the ball with the best of them, it is hard to imagine him walking away.
The last time Brady was sacked less than 20 times in a season was in 2009 when the Patriots ranked 10th in rushing attempts, 12th in yards and sixth in touchdowns.
With defenses being forced to respect the running and play-action pass game, the likelihood of seeing another 32-sack season like 2011 again are slim to none.