There was a time when it looked like James Harrison wasn't going to have an NFL future.
Harrison signed with the Steelers as an undrafted rookie in 2002, spending two years on and off the Pittsburgh practice squad, occasionally making the active roster as a special teams player.
Following a brief stint with the Baltimore Ravens/Rhein Fire of NFL Europe, Harrison was cut for the fourth time in his professional career.
The five-time Pro Bowler considered walking away from the game completely, but a weightlifting injury sustained by Steelers linebacker Clark Haggans meant there was a roster spot for Harrison.
The Kent State alum stayed with Pittsburgh for the next nine seasons, racking up 456 tackles, 64 sacks and two Super Bowl rings in the process.
A breakdown in contract negotiations meant Harrison spent the 2013 season with the Cincinnati Bengals, but he was back in black and yellow for 2014.
Now, at the ripe, old age of 37, Harrison is gearing up for a 12th NFL season.
While most dudes would have to be out of their minds to even attempt to play in the trenches at this point, Harrison appears to be in the best shape of his life.
Here's how he's been training to not only play, but physically dominate the 2015 NFL season.
James Harrison may be 37, but he's showing no signs of slowing down.
That's probably because he does skull crushers with a resistance band.
Or maybe it's because he bench presses without a bench.
Look away now, every quarterback but Russell Wilson, because James Harrison is hungry.
So hungry, in fact, that he needs three grills to replenish those muscles.
This is by far the least fun game of Newcomb in the history of the world.
But it definitely looks like a blast compared to what James calls "cutting grass"...
Which he actually does in between sets.
When there's no more room left on the bar, you gotta dangle 45-pound plates on the side.
In case you thought Harrison was all bulk and no speed, though.
This is how you get legs the size of tree trunks.
And shoulders the size of cantaloupes.
Doing dips with 225 pounds strapped to him is light work for Harrison.
But putting 675 pounds on the cage looks like it's actually one of the hardest things to do in life.
We want none of that, James.
One, two, three... 24 plates?!?!
Lifting weights is crucial for Harrison, but it don't mean a thing without that cardio grind.
And he knows a strong core is key to seeing gains everywhere else.
It doesn't hurt to have a recovery plan that includes massages and acupuncture, either.
As well as a squad that's ready to help him challenge for another Super Bowl ring.