But it has remained largely hidden because of Lesnar's famous reticence to allow the media into his life.
Now Lesnar has revealed the cover of his new autobiography "Death Clutch: My Story of Determination, Domination, and Survival."
"It's a book about my life story," Lesnar explains in the video below. "My fight to the top through the WWE and the UFC, despite all the doubters, and despite fighting through injuries and illness."
For those unfamiliar with the significance of the title, Death Clutch is Lesnar's signature brand of clothing, as well as his gym--pretty much his personal brand, almost as much as his given name.
Here's a video of Lesnar explaining his book to fans:
Lesnar surprised the world when it was announced Brock will star on the upcoming season of the Ultimate Fighter, allowing cameras to film him at length and unscripted for the first time in his career.
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