Boxers work out differently for a fight than when they are working to stay in shape between them. Even though they are highly trained athletes with knowledgeable trainers, they are still prone to believing in "wives tales" and the idea that "harder is better". They may push themselves slightly beyond the limits of where they can fully recuperate. Remember that to get stronger you have to break down muscle so that it repairs itself. You have to push your heart and lungs to just below total fatigue to gain the benefits of recuperation. You have to rest enough, but not too much so that you fully heal but do not lose any of the gains through natural atrophy. It is becoming easier to gauge those levels, but it is still not an exact science.
Over training can happen but should be very rare in this day and age at the top levels of the sports world because of all the information on how to avoid it. I know that it takes a lot of experience to know hoe and when to taper your training to get to peak perfection for fight time and at the top level of boxing nothing less should be expected.
Any top sportsman trains so he at his peak on the day of the big event. Olympic athlete's look to be in perfect shape when the big day comes along and its the same with boxers. You need to be at the top of the curve and not leave your best days in the gym.
Make sure to eat fried chicken as a regular diet. Have meal portions of hog maws, cornbread, collard greens, babyback ribs, and sweet potatos as well. Good luck.
@Topica-Soul foods enhance your performance, trust me.
I consistently hear the excuse that a boxer over trained for a fight. And this excuse is blamed for a lackluster performance. Old school fighters and even some fighters today are gym rats that are ALWAYS training and ALWAYS in shape. If given the proper rest time to recoup just before the bout, just how does over training effect the fighter's performance? I'm incline to think that this is an excuse used way too often.