Originally Posted by Brickhaus
More muscle uses more oxygen, period. A guy with more muscle needs to do more to have better endurance. It's simple biology.
No it's not, muscle is capillarised and holds stores of haemoglobin, glycogen and creatine to power it when it needs it. Your stroke volume (central) doesn't provide all the oxygen, there are peripheral (muscle) adaptations from training. More muscle improves your stamina if it was built with your sport in mind.