Why is stamina an issue for some fighters?

Stamina issues usually effect the puncher/slugger type fighter. They tend to punch themselves out more than any other fighting style; Especially the heavyweights. I guess it's because they like for their fights to end early with throwing so many more power punches, by putting so much force and body weight behind their shots that they forget the jab. Then the longer the fight goes their punches lose steam. Examples of these type of fighters are: Miguel Cotto, Pre Manny Steward Wladimir Klitschko, Thomas Hearns and George Foreman and Earnie Shavers.

Not genetics IMO.Either they're working on their cardio or they're not as hard as they should. Plus getting punched and missing punches take alot from you. That's why rigo and Floyd don't get do tired. They're not wasting punches and not getting hit alot genetics def play a factor.... Just think of it this way pretty much all pro top level fighters train extremely hard... in the end some have better stamina then others. a guy like gamboa could do the same exact training as pacquiao but despite that i bet u gamboa is going to fade at one pt while pacman wont,, just using an example

Always fight or play in at your speed and momentum or the next person will drain your gas tank and stall you

Simple..some throw to much in every punch, some do not know how to relax in a fight. It basically comes down to that..you do not throw ko punches with every shot and you have to learn how to breath and remain calm....over excitment and nervousness can kill your gas tank in any sport

Not genetics IMO. Either they're working on their cardio or they're not as hard as they should. Plus getting punched and missing punches take alot from you. That's why rigo and Floyd don't get do tired. They're not wasting punches and not getting hit alot How can genetics not be a major player , when you have fast and slow twitch muscle fibre , when lung capacity heart score etc are all an individual thing , nerve impulses fire at different speeds in different people the list is a mile long and its all genetic based .

Not genetics IMO. Either they're working on their cardio or they're not as hard as they should. Plus getting punched and missing punches take alot from you. That's why rigo and Floyd don't get do tired. They're not wasting punches and not getting hit alot

Its genetic as well as training , some guys are lazy trainers or work within their comfort zone some are pushing all the time but know their body and when to ease off , there is also a psychological element to it that plays a very big part , then you have the nervous system , for instance if youre high strung and cant relax in the fight it will sap your energy , your level of hydration can come into it , some guys are always fighting semi dehydrated because they are fighting in a weight class that they can barely make , but the advantage of being bigger in the fight might compliment their style so they run with that . So as you can see many things effect perceived stamina .

Some fighters seem like they don't slack during training camp and train for stamina like every other fighter however the gas out a lot quicker even when their work rate isn't that high, a perfect example of this is Canelo. Is it a genetic thing that goes unnoticed unlike a chin which we can all agree you can't train for? Genetic differences, and you really have no idea what a fighter is doing in camp unless you have access to their training schedule. If there was not training footage and everyone in camp played along, JCC Jr could easily have claimed he trained like an animal for the Sergio fight and no one would be any the wiser. You just don't now what guys are really doing, or what they're training for.

I've also noticed this. Some cases like Canelo may be due to the drastic change in weight overnight.

genetics.......... some burn nervous energy before the fight I was going to say genetics as well

everybody's body is different............ could be genetics........... some burn nervous energy before the fight

you know i wonder the same thing as well...