Derrick:
Aerobic Endurance and Power Maintenance (read endurance and maximal production) are complementary and on fight night those qualities need to be expressed optimally. As I stated Maximal Strength and Power are highly variable when not worked. The problem typically is in the design of the program as Carl pointed out. Most of the work done in the Power Endurance phase as described by most is not specific enough for preparing someone for competition (not to mention most applications of PE are wrong IMHO). When working with weights, the power endurance gained from weight sessions focusing on long periods (>20s) of wattage don’t help maintain maximal power. While on the other hand working with weights to maintain or increase max strength and power does keep those power producing capabilities while leaving the specific work being done as conditioning work. Contrary to what you wouldn’t do and I haven’t trained a fighter but I would want a fighter to work specifically @85%+ intensity of what the average fight intensity is going to be 2-3 days a week up until the final two weeks before a fight in the last 5 to 8 weeks, recover and tune the last two weeks, fight, take a week off with minimal conditioning, then start another 8-12 week cycle which starts out with shorter higher intensity bouts which get longer the longer we are in the cycle and high intensity weightlifting for the first 6-7 weeks with training days last 5-8 hours in duration gradually getting that down 2-3 hours 4-5 weeks out from the competition.
A single workout session should not be thought of as a power endurance session, all workout sessions directly effect power endurance. A phase or cycle of training should not be thought of as a power endurance phase or cycle as every phase of training affects power endurance. Power Endurance should be thought of as a tool to guide in training and conditioning an athlete, ie what are physical demands of the sport to compete not only competently, but also competitively every time we wish compete, how long between competitions, how long is the competitive season, how long a single competition last, the intermittent rest to competition ratio of the sport.