In the sport of Mixed Martial Arts, fighters are categorized by one thing. Not, their records, fighting styles, or camps they come out of, but by weight.
Weight-classes range from 125-pound Flyweights, to 265-pound Heavyweights. Since the inception of weight classes, many fighters bulk up or cut down to make their respective weight, but they generally fought in the same class every time, until recently.
Many fighters have been "weight-jumping" as of late, fighting in multiple weight classes, and while there are different reasons for different fighters, each jump sparks new questions for the sport.
This new trend of weight-jumping seems to be most popular in MMA's lead promotion, the UFC. With their 205-pound Light Heavyweight division being the most dynamic in the sport, it's no wonder that most weight-jumping involves this class.
We've seen fighters like Brandon Vera, and Jake O'Brien come down from the Heavyweight division, and others like former Middleweight champion Rich Franklin and Matt Hamill coming up from the 185 pound Middleweight division, to try to find success at a new weight.
Other fighters like current Middleweight champion Anderson Silva seem to be weight-jumping for other reasons.
Having beaten all the competition at 185 pounds, Anderson Silva jumped up to 205 pounds to take on James Irvin in July 2008. Silva was successful in his jump, beating Irvin at just over one minute in the first round.
After a successful title defense against Thales Leites in April, Silva now plans to jump back to the 205-pound division to take on former Light Heavyweight champion Forrest Griffin at UFC 101 in August.
The Lightweight division has also seen some weight-jumping as of recent with Lightweight champion BJ Penn jumping up to 170 Lbs. to face Welterweight champion Georges St. Pierre.
After being stopped at the end of the fourth round by St. Pierre, Penn will now jump back to Lightweight to defend his title against No. 1 contender Kenny Florian alongside Silva and Griffin on the August card.
Diego Sanchez has also jumped down from Welterweight to prove himself as a top contender at 155 pounds.
But how is all of this affecting the organization? After Silva's first jump to 205 Lbs. he then dropped back to Middleweight, to take on then-No. 1 contender, Patrick Cote.
A knee injury to Cote in the third round, gave Silva the victory, but much controversy was sparked due to a lack-luster performance by Silva in the first two rounds.
While Silva made weight, and even finished the last two rounds in his locker room with his training partner, the question is raised as to whether or not his need to drop 20 pounds had an effect on the way he fought.
No official reason was given as to why Silva fought the way he did, but the effects that cutting weight can have on the body, may have been what kept Silva from being the exciting, dynamic striker he's known to be.
Weight jumping has also been used to create "super fights," in which fights that would not have been possible, due to weight class differences, can be made a reality.
UFC 99 saw Rich Franklin and Wanderlei Silva fighting at a catch-weight of 195 Lbs. which is not an official weight class in the UFC.
The decided weight caught the two fighters in the midst of a jump, Franklin going up from 185 to 205 Lbs. and Wanderlei moving down between the same weights.
Another "superfight" was between Georges St. Pierre, and BJ Penn, both title holders at their respective weight class. The fight, at 170 pounds, put the GSP's Welterweight title up for contention, meanwhile leaving Penn's Lightweight belt locked until he dropped back to 155 pounds.
Top contender Kenny Florian gained his status with a submission win over Joe Stevenson back in November 2008, but due to Penn's "superfight" in January 2009, Florian will have to wait till August to get his title shot.
While Florian has never expressed any dislike to the situation, the main supporters of the UFC, the fans, may see things differently.
Some may not have agreed with holding off on a possibly exciting Lightweight title bout, for a grudge match "superfight" which failed to live up to its hype.
With 2009 in full swing, we are sure to see much more of this new trend, along with important legal battles, contract disputes, and new fighters.
It's not certain whether weight jumping will harm or help the sport in the long run, but in the meantime, all we can do is sit back, enjoy the fights, and play the "weighting" game.