I think too much muscles means less speed and less stamnia probably the reflex too because of the bulk.
Your less likely to get injured doing body weight exercises than you are lifting weights, body weight exercises are more useful for a boxer to do anyway.
The key to boxing is strength endurance. Most fighters will perform endless calisthenics like pushups, situps, and pullups to achieve this, while others will perform high reps of light weights. Some examples are: Kostya Tszyu used to bench press half his weight 70 times. Roy Jones Jr used to do high-rep, low weights for his legs. Frank Bruno used to do insane reps on the cable machines.
It's because boxing trainers are largely ignorant of proper strength training methods... and there is an unwarranted tradition and myth of weights being "bad" for a boxer, although this has already been disproven so many times, it's a wonder why anyone still believes it!
It takes too much to maintain too much muscle proportion to your bone proportions. Basically. The more muscle you have, the more calories it takes to maintain them, so you basically get tired, faster depending on your caloric intake during a fight.. I don't think we ever saw Shane Mosely eating a ham sandwitch in the 6th round of any of his fights..
IMO there is no point of that, it builds endurance and you already work endurance enough by working the bag, jumping rope, speed bag, running.
The more muscle you have, the quicker you can tire. As maintaining a lot of muscle requires a lot of calories.. Basically.. Say you weigh 180 lbs and are around 40% muscle, 10% fat, 40% bone density.. You will burn more calories just sitting down than someone who is say.. 180 lbs and around 30% muscle, 20% fat, and 40% bone density.. This means you have a higher caloric requirement to sustain yourself.. In a situation where you are utilizing a lot of calories.. Like in a 3-12 round fight. The person who has more muscle of these two examples is going to tire quicker.. This is part of the explanation behind people talking about shane mosely fighting in one or two punches and being too muscular for a period of time in his career.. It could have been that he was too muscular, and exhausting more quickly than he would if he had put on fat, or simply over hydrated.
WTF?? that was WAY off the mark!!! "boxbible" was correct about myths and silly information...i am no pro boxing champion, but i AM a Physiotherapist who played pro ball in the past... 12 rounds is nowhere near enough time to start burning a significant amount of your body fat, much less totally burn it out!!! body fat is a waste, at least above 5%ish, which is quite lean. proper strength/weight training is essential. i feel a big problem is the lack of flexibility training to go along with it...THAT is when the bulkiness becomes a problem. one should do strength training that simulates the sport you are in to the best degree. and some pure weight training is quite helpful, too. MYTHS are a HUGE problem in nearly all sports!!!
i dont think the weight raining is bad but how you do it is. most people who dont know how to do it properlly for the sport they are in will often be told that less reps high weight will get them stronger and bigger quicker but lets say if they are boxers and they do that they get bigger and stronger but they would lose that muscle repition and endurance in the muscle... i was told to do low weight high reps to build strengh and endurance with out it slowing you down at all
Most boxing trainers don't have much knowledge on weightlifting so they stick to teaching there boxers traditional bodyweight exercises.
low reps high weight does not make you bigger unless you consume more calories and keep your weight training one or two days a week.