Turns out the most dangerous opponent Junior dos Santos ever faced was himself.
The former Ultimate Fighting Championship (UFC) heavyweight champion was training so hard prior to his UFC 155 title fight against Cain Velasquez, which took place last December in "Sin City," that he developed rhabdomyolysis, a (sometimes fatal) breakdown of muscle fibers that releases their contents into the bloodstream.
That's the kind of thing that can happen when you train six hours a day for three months straight.
Dos Santos was beaten pillar to post by Velasquez, coughing up his title and nearly his life, thanks to the undue stress he caused his kidneys (details here). In addition, he had to spend the next several days wearing one of the gnarliest punch faces in the history of combat sports.
See the gruesome photo gallery here.
Adverse effects in the long run? Pfffft. Turns out the rewards outweighs the risks, and "Cigano" tells Yahoo! Sports he's going to continue fighting -- albeit with a revamped training camp -- because this is his life and fighting is what he loves to do.
"You know, I think it's worth it. This is my life. This is everything I have. People don't know how hard we [work] and what we sacrifice to [be successful]. MMA athletes train so much, you know. I would continue to [do what I'm doing]. I want it so badly. I want to give everything I have to this. This is everything to me."
We'll see how he feels about that on Sunday morning.
That's because Dos Santos is booked to swing leather against Mark Hunt in the co-main event of the UFC 160: "Velasquez vs. Bigfoot 2" pay-per-view (PPV) event, which takes place on May 25, 2013 at the MGM Grand Garden Arena in Las Vegas, Nevada.
And the "Super Samoan" knows a thing or two about hurting people.