He may have been 'The World's Most Dangerous Man' but Ken Shamrock had a rare smile on his face when he spoke out to endorse Life Shotz, an all-natural energy drink.

The four-time UFC champion praised the shots after he discovered them at one of the US's premier amateur wrestling camps.

“I watched all these kids rolling around, all the energy they had, and, man, I was thinking to myself, ‘I wish I had that type of energy,’” Shamrock said. “After about a week, it's one of those subtle things, when you don't realize the things you're getting done in one day.

You just start going through it, and all of sudden you have all this energy. I had more alertness, more energy, more desire to come in and train.” Known for his aggressive work rate, if Shamrock's chucking it down his throat, you know it's good stuff...

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