Two week of being in Colorado looked like it wasn't enough time to get DeMarcus Corley ready for his fight with Manuel "Manos" Perez. Corley had breathing issues with the altitude in Colorado during the match. Perez might have known that and definitely took advantage of that opportunity to put more pressure on Corley. After the sixth round was over Corley told his corner and the referee he could not continue so the bout was stopped.
Corley is now 42-23-1, (25 KO's) while Perez's record rises to 23-11-1, (5 KO's).
Here is some info about training in high altitude areas.
Results from Altitude Training
Athletes in every sport across the world are realizing the benefits that altitude training can have on ones performance, regarding overall strength, power and endurance. It is the only legal way to get a physiological edge of the competition, and popularity amongst athletes has continued to grow. Through a combination of sleeping in normobaric hypoxia every night and moderately working out at altitude 2-3 times per week, athletes can increase performance to otherwise unachievable levels. Scientific studies have shown improvements in performance by as much as 3%.