I found this article about Terrell Suggs from a couple of years ago. Maybe Sizzle really just is crazy off the field.
The tires come into play on "Strongman Hill," a dirt slope tucked into the Santa Monica Mountains, where there's always a shovel on hand in case of a chance rattlesnake encounter. Rather than simply running up the path, the players might have the waist-high, 75-pound tires tethered behind them, or strapped to their bodies, or flop them up the hill end over end. When they aren't pushing or pulling the waist-high wheels, they're pounding them with sledgehammers.This workout seems to be from the same people who produced the video we saw of Suggs' workout.
[ LA Times ]