Why does Shogun gas so quickly? Bad cardio or taking too much damage?

Seriously WHAT THE FUCK?!

vs Machida 1 - pressed the action in 5 full rounds and was fine. no cardio problems

vs Machida 2 - made quick work of him in 1 round. no cardio problems

vs Bones...

Source: http://ninjashoes.net/forum/showthread.php?78981-Why-does-Shogun-gas-so-quickly-Bad-cardio-or-taking-too-much-damage&goto=newpost

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