For some reason the definition of "toughness" on this thread derives from the risk to life and limb. Therefore, How could any MMA athlete compare their "toughness" to a free style mountain climber or a sky diver?
I repeat, the debate is about "Mental Toughness". Almost every MMA athlete rides a wave of euphoria throughout an MMA bout. This is a primary attraction to the sport for many "adrenaline junkies". I don't want to have to say this but, For most MMA practitioners there is very little mental aspect to their fighting style. They enter the octagon to enact certain trained aspects of fighting and can be reassured by the fact they will be relatively unharmed if they fail because a referee will save them. Does that constitute mental toughness?