We've all seen the improvement in BJ Penn since his loss to GSP. A new training regimen, attitude, and drive have all combined to turn Penn into an absolute beast. At 155 lbs.
After watching him dismantle both Kenny Florian and Diego Sanchez while barely breaking a sweat and never being put in any kind of danger the knee jerk reaction is that Penn should seek stiffer challenges in the welterweight division.
While Penn has competed successfully in the past at 170lbs and could very likely pose a threat to some of the top ranked welterweights his next assault on the division needs to take a different approach.
Could Penn jump into the log jammed welterweight division tomorrow and find success? Yes. Should he? No. He should take a page from the Georges St. Pierre book of MMA and take a more scientific approach.
In fact Penn is already halfway there. The training regimen that turned him into a beast at 155 could be tailored to allow him to gain additional mass without losing any of his quickness. This is same approach GSP has said he would take if he were to ever set his sights on the middleweight division.
GSP has stated numerous times that he wouldn't simple compete at middleweight because he naturally weighs 190 or so pounds. He would need to take an undetermined amount of time to add muscle to his frame in a manner that wouldn't have any negative side effects on his speed and explosiveness.
GSP would cut down to 185 just as he does to get to 170 under this approach. Penn should likewise build up to a weight higher than 170 and then cut down. The difficulty (for fans) is that this would be a more time consuming route to the welterweight division.
In fact Penn very well may need to completely abandon his lightweight crown if he truly wants to face the top tier fighters at welterweight. We've already seen the results of riding the fence and coming in under weight. There is no reason for us to believe that things would be any different not only against GSP but the other highly ranked challengers as well.
While I'm not a doctor or professional athletic trainer I do know that it is typically harder for a smaller athlete to make mass gains than it is for a larger athlete. Frank Mir for example added over twenty pounds of muscle over the course of the five months since his defeat at the hands of Brock Lesnar.
Mir went on to explain in his post UFC 107 interviews that he hasn't suffered any loss in speed or agility and that he plans on adding additional mass so that he has to cut down to the 265lb heavyweight limit.
Although Mir and Lesnar are in the same division their size disparity is very similar to the disparity between Penn and GSP. Mir increased his weight by approximately 8% over the course of five months and still wants to achieve additional gains.
Therefor we should expect that in order for Penn to take this same approach it would take at least five months to build himself into a welterweight fighter. With many of the UFC champions sidelined I don't expect that UFC brass is going to allow him to undertake this experiment immediately.
Another title defense against Frankie Edgar or Gray Maynard would be appropriate and then possibly a catch weight fight with a fighter from the welterweight division would give Penn a preview of what to expect physically for his return to welterweight.
The hardest thing for Penn fans to swallow may be the timetable Penn requires to make this transition and that it might not fit into the organizational plans of the UFC. After all if we can agree that Penn cannot take on the welterweight division while riding the fence at 160-something pounds he'll need to fully commit to being a welterweight. At least until he gets it's highest reward strapped around his waist.